sodium-dodecyl-sulfate and Erythema

Glove occlusion might enhance skin sensitivity to a subsequent detergent challenge (occlusion effect). Thus, some skin protection creams (PC) claim to protect against this effect of occlusion, and are recommended to be used before wearing liquid-proof gloves.. To evaluate the effect of PC applied prior to glove occlusion on the 'occlusion effect'-refers to increased susceptibility of the skin to a model detergent.. One hundred and eleven volunteers were enrolled in a single-blind, randomized study. Seven PCs were applied before glove occlusion over 7 days (D1-D7). After sodium lauryl sulphate (SLS) challenge, we compared the irritation between the areas treated with PC and occlusion alone. Clinical scoring and bioengineering methods (capacitance, transepidermal water loss [TEWL], and colourimetry [erythema]) were used to quantify the irritant reactions.. After 1 week of occlusion and PC application, we did not observe significant changes in TEWL, nor in erythema, whereas skin hydration raised in three cream-treated areas. On day 10, after a challenge with SLS, some products significantly aggravated the skin irritation as compared to occlusion alone.. The 'occlusion effect'-shown as higher skin susceptibility to a model detergent-was not mitigated by PCs when applied prior to glove occlusion. On the contrary, some PCs might have negative effects on skin barrier function and augment such sensitivity.

Topics: Dermatitis, Allergic Contact; Dermatitis, Irritant; Detergents; Emollients; Erythema; Humans; Single-Blind Method; Skin; Sodium Dodecyl Sulfate; Water; Water Loss, Insensible

Human in vivo models of skin damage were often used in research of cutaneous disorders. The most commonly used models were tape-stripping as mechanical, sodium lauryl sulphate-induced irritation as chemical and ultraviolet radiation as physical damage model. In regard to differences between models, they were expected to have different responses to damage and recovery, with unique skin parameters' changes over time.. The aim was to compare skin parameters in three different skin damage models on the same anatomical location, with and without topical treatment.. Four test sites on each forearm were randomly assigned to three skin damage models with the fourth sites on each forearm chosen as a control, undamaged site. Skin parameters were assessed using non-invasive methods.. Sodium lauryl sulphate irritation caused the strongest damage with delayed reaction to the irritant. Tape stripping leads to highest initial skin barrier disruption but afterwards it showed the fastest skin recovery. Ultraviolet radiation did not affect skin barrier function, but it elevated skin erythema and melanin level. Tested preparation did not lead to changes in measured parameters.. The skin of the participants had different response to three skin damage models with distinct changes of skin parameters and recovery. The trial was registered at ClinicalTrials.gov under the identifier NCT03783819.

Topics: Administration, Topical; Erythema; Humans; Skin; Sodium Dodecyl Sulfate; Ultraviolet Rays; Water Loss, Insensible

Elevated levels of skin sebum are associated with the growth of Propionibacterium acnes. Intensive degreasing of the skin reduces Propionibacterium acnes but also may cause skin irritation.. We assessed the degreasing effect and skin tolerability of a botanical face cleanser with hops and willow bark extract and disodium cocoyl glutamate as mild cleansing agent compared to a standard face cleanser with sodium laureth sulfate (SLES).. A total of 21 healthy volunteers with normal to oily skin were enrolled in this study. Both cleansers were applied twice a day on the left or right side of the forehead for 15 days in a standardized manner. Bioengineering measurements were performed on day 8 and 15 and on day 17 after an application break of 48 hours. The sebum level was determined using a Sebumeter. The botanical face cleanser significantly reduced the sebum level (P < .01) in the test area on day 17. The SLES containing cleanser showed a statistically relevant degreasing effect already on day 15, but after the application break the sebum level increased again on day 17. None of the cleansers caused skin irritation as determined by skin redness measurements.. In contrast to the SLES containing cleanser, the botanical skin cleanser with hops and willow bark extract had a continuous degreasing effect without reactive seborrhoe after the treatment break. Skin cleansing without SLES might be advantageous for sensitive skin.

Topics: Adult; Erythema; Female; Healthy Volunteers; Humans; Male; Middle Aged; Photometry; Plant Extracts; Sebum; Severity of Illness Index; Skin; Skin Cream; Sodium Dodecyl Sulfate; Treatment Outcome; Young Adult

The objective of our study was to investigate the tandem irritation potential of two organic solvents with concurrent exposure to the hydrophilic detergent irritant sodium lauryl sulphate (SLS). A tandem repeated irritation test was performed with two undiluted organic solvents, cumene (C) and octane (O), with either alternating application with SLS 0.5% or twice daily application of each irritant alone in 27 volunteers on the skin of the back. The cumulative irritation induced over 4 days was quantified using visual scoring and non-invasive bioengineering measurements (skin colour reflectance, skin hydration and transepidermal water loss). Repeated application of C/SLS and O/SLS induced more decline of stratum corneum hydration and higher degrees of clinical irritation and erythema compared to each irritant alone. Our results demonstrate a further example of additive harmful skin effects induced by particular skin irritants and indicate that exposure to organic solvents together with detergents may increase the risk of acquiring occupational contact dermatitis.

Topics: Adolescent; Adult; Dermatitis, Irritant; Erythema; Female; Humans; Irritants; Male; Single-Blind Method; Skin; Sodium Dodecyl Sulfate; Solvents; Surface-Active Agents; Water Loss, Insensible; Young Adult

To compare the functional stability of Cetaphil UVA/UVB Defense SPF 50 as measured by its ultraviolet B sun protection factor (UVB-SPF) and ultraviolet A protection factor (UVA-PF) values following exposure to natural sunlight versus the UVB-SPF and UVA-PF values of unexposed product.. These two randomized, controlled, evaluator-blinded, single-center trials were conducted according to the methods outlined in the 2007 Proposed Amendment to the Final Monograph, “Sunscreen Drug Products for Over-the-Counter Human Use.” Sunscreen samples were applied to glass plates and exposed to ultraviolet radiation in the form of natural sunlight in four minimal erythemal doses (MED) ranging from 2–6 MED (42–36 mJ/cm2). Three test sites were identified on the back of each study subject. Exposed sunscreen (one of four doses), unexposed sunscreen, and a UVB-SPF 15 control sunscreen were applied to the three test sites in a randomized fashion, followed by UV irradiation of incremental doses. Erythema and pigment darkening responses were assessed immediately following UV exposure and again 16–24 hours (erythema) or three to 24 hours (pigment darkening) after exposure. UVB-SPF and UVA-PF values were calculated for the exposed and unexposed samples.. The calculated UVB-SPF and UVA-PF values for all test samples (exposed and unexposed) were >50 and >9, respectively, which were greater than the stated UVB-SPF and UVA-PF values on the product label. No differences were observed between the exposed and unexposed samples in UVB-SPF or UVA-PF.. The UVA and UVB protection using standard evaluation techniques of Cetaphil UVA/UVB Defense SPF 50 remains stable despite exposure of the sunscreen to natural sunlight containing UVB ranging from 2–16 MED (41–336 mJ/cm2) and coexistent UVA.

Topics: Drug Combinations; Erythema; Female; Humans; Male; Product Labeling; Propylene Glycols; Skin; Sodium Dodecyl Sulfate; Solar System; Sunburn; Sunlight; Sunscreening Agents; Suntan; Treatment Outcome; Ultraviolet Rays

The skin barrier, located in the stratum corneum, is influenced mainly by the lipid and protein composition of this layer. In eczematous diseases impairment of the skin barrier is thought to be of prime importance. Topical anti-inflammatory drugs and emollients are the most widely used eczema treatments. The aim of this study was to examine the effects of topically applied corticosteroid, tacrolimus and emollient on stratum corneum lipids and barrier parameters. Nineteen healthy volunteers participated in the study. Both forearms of the subjects were divided into four areas, which were treated twice daily for one week with betamethasone, tacrolimus, emollient, or left untreated, respectively. After one week each area was challenged with a 24 h sodium lauryl sulphate patch test. The lipids were collected using the cyanoacrylate method and evaluated by high performance thin layer chromatography. For evaluation of the skin barrier, transepidermal water loss, erythema and electrical capacitance were measured. The ceramide/cholesterol ratio was increased in betamethasone- (p = 0.008) and tacrolimus-treated (p = 0.025) skin compared with emollient-treated skin. No differences in ceramide subgroups were found between treatment regimes. Pretreatment with betamethasone (p = 0.01) or with tacrolimus (p = 0.001) causes a decreased inflammatory response to sodium lauryl sulphate compared with emollient. In conclusion, treatment with betamethasone and tacrolimus has a positive effect on the ceramide/cholesterol ratio and susceptibility to irritant reaction compared with an emollient.

Topics: Administration, Topical; Adolescent; Adrenal Cortex Hormones; Adult; Betamethasone; Ceramides; Cholesterol; Chromatography, High Pressure Liquid; Denmark; Dermatitis, Irritant; Electric Capacitance; Emollients; Erythema; Female; Forearm; Humans; Immunosuppressive Agents; Male; Middle Aged; Skin; Skin Irritancy Tests; Sodium Dodecyl Sulfate; Tacrolimus; Time Factors; Water Loss, Insensible; Young Adult

Sensitive skin is a subject of intense research work. However, its contours have not been defined and properly investigated so far. The aim of this work was to characterize objectively the consumers of cosmetic products, which referred skin susceptibility to several agents or conditions.. Twenty-four healthy female volunteers, mean age 38.9+/-13 years were recruited. The volunteers were fully informed about the study having previously expressed their consent, and were grouped in to I: individuals without any skin sensitivity complaint and II: individuals with self-reported sensitive skin to regular contact with household cleaning products. Sodium lauryl sulphate was used as a 'provocative' agent and it was applied on the back of the volunteers' hands, as an occlusive patch for 24 h. After the patch removal (30 min, 7 and 14 days), the variables erythema, transepidermal water loss, stratum corneum hydration and blood perfusion were measured.. No evidence of a statistical difference was found between the biomechanical behaviour of the skin of the two groups.. The results of our study did not enable us to establish a clear discrimination between sensitive and non-sensitive skin, which once again underlines the subjective nature of this condition.

Topics: Adult; Bioengineering; Cosmetics; Dermatitis, Contact; Erythema; Female; Follow-Up Studies; Household Products; Humans; Irritants; Middle Aged; Models, Biological; Patch Tests; Skin; Skin Absorption; Skin Irritancy Tests; Sodium Dodecyl Sulfate; Water

We performed a randomized, paired, double-blind trial involving 14 participants with self-declared normal skin and 15 participants with self-declared sensitive skin to test the cutaneous compatibility of materials of low irritation potential for skin irritation (sanitary pads) elicited by repetitive topical application.. Two test products patches and two control substance patches were applied to the lateral aspect of the upper arm once daily under fully occlusive conditions for 4 days. The positive control patch was moistened with sodium lauryl sulphate (0.1% w/v) and the negative control patch was moistened with 0.9% sodium chloride, as were the two test material patches. The patches were removed, skin irritation (erythema) graded, and new patches applied after each 24-hour period.. There was no significant difference in skin irritation from the test patches between the sensitive and normal skin groups. The two test patches and the negative control patch were significantly less irritating than the positive control in both test groups. Both test patches were comparable to the negative control patch in the normal and sensitive skin groups.. The test materials produced similar degrees of skin irritation among both groups. Overall, there was no statistically significant difference in skin compatibility when the two feminine hygiene product test patches were worn by self-declared normal and sensitive skin groups.

Topics: Adult; Aged; Analysis of Variance; Dermatitis, Allergic Contact; Dermatitis, Irritant; Double-Blind Method; Erythema; Female; Humans; Male; Menstrual Hygiene Products; Middle Aged; Severity of Illness Index; Skin; Skin Irritancy Tests; Sodium Chloride; Sodium Dodecyl Sulfate; Time Factors

Cold and allergy sufferers often develop irritation around the nostrils as a result of repeated and frequent rubbing of the skin site with facial tissues. This irritation is a combination of the inherent irritant properties of the tissue components (chemical irritation), and mechanical irritation from friction. Lotion-coated facial tissues are being developed to provide soothing, skin benefits, and to promote healing of this type of irritation. The objective of these studies was to evaluate the efficacy of different lotion formulations on facial tissues in preventing irritation, or aiding in the healing of irritation.. The modified forearm-controlled application test (Modified FCAT) was adapted as a means of quickly evaluating the relative skin benefits of various lotion formulations used to coat facial tissues. The test was conducted on the volar surface of the forearms of volunteer subjects. Test sites were pretreated with 24 h occlusive patches of sodium lauryl sulfate (SLS) to induce mild or moderate skin irritation. This was followed by repeated wiping of the lotion-coated tissues. Irritation was evaluated using visual scoring for erythema and dryness. Lotion formulation options were compared in the model. Comparisons included assessments of the type of fatty alcohol in the formulation (stearyl and cetearyl alcohol), the presence of silicone and the base formulation (mineral oil, petrolatum of a proprietary formula).. Differences in the degree of erythema and dryness were detected among various formulation options. No differences were found between formulations containing stearyl or cetearyl alcohol. Low levels of silicone produced benefits in one of two experiments. The proprietary base formula produced greater reductions in erythema following treatment of SLS-irritated skin compared with mineral oil and petrolatum bases.. The results indicated that this modification of the FCAT can be used to compare various lotion formulations for skin benefits and healing properties, and to rank qualitatively the benefits of various formulation options.

Topics: Adolescent; Adult; Chemistry, Pharmaceutical; Cosmetics; Dermatitis, Contact; Emollients; Erythema; Fatty Alcohols; Female; Forearm; Humans; Irritants; Middle Aged; Mineral Oil; Paper; Petrolatum; Silicones; Skin Irritancy Tests; Sodium Dodecyl Sulfate

Lipophilic extracts of Isatis tinctoria L. exhibit significant activity against several clinically relevant targets of inflammation. The alkaloid tryptanthrin was identified as one of the active principles in woad and characterised as a potent dual inhibitor of COX-2 and 5-LOX. Here, the anti-inflammatory efficacy of topical application of three different Isatis extracts and tryptanthrin was investigated in human volunteers. Two different models were used, namely the sodium lauryl sulphate (SLS)-induced irritant contact dermatitis (ICD) and UVB-induced erythema. Twenty healthy volunteers without any skin disease participated in the study. Cumulative irritant contact dermatitis was induced on test fields on the volunteers' backs by twice daily application of 0.5 % sodium lauryl sulphate over a period of four days. Half of the test fields were treated with the test substances during the eliciting phase, while the remaining test fields were treated over a period of 4 days after induction of dermatitis. In the second model, a UVB erythema on the volunteers' lower backs was induced using the double minimal erythema dose (MED). Twenty-four hours after irradiation the test fields were treated with the test substances over a period of 3 days. All reactions were assessed visually and by non-invasive bioengineering methods (evaporimetry and chromametry). Treatment with extracts during the ICD eliciting phase led to a significantly smaller increase of visual scores and transepidermal water loss compared to the untreated test field. For tryptanthrin this benefit was also observed, but the improvement was not statistically significant. When treatment was performed after completing the eliciting phase, accelerated resolution of the irritant reaction could not be observed. In the UVB erythema model anti-inflammatory effects of the test substances were not observed.

Topics: Adolescent; Adult; Anti-Inflammatory Agents; Dermatitis, Allergic Contact; Drugs, Chinese Herbal; Erythema; Female; Humans; Isatis; Male; Phytotherapy; Plant Extracts; Plant Leaves; Quinazolines; Single-Blind Method; Sodium Dodecyl Sulfate; Treatment Outcome; Ultraviolet Rays

It is known that, depending on the concentration, treatment with urea could improve skin barrier function, despite its penetration-enhancing properties. This controversial skin effect of urea has been explored systematically in this study in terms of the effect of vehicle on the performance of urea. In the first part, a series of four semi-solid emulsions with 5% (w/w) urea, varying in the type of emulsion, nature of emulsifier and polarity of oil ingredients, have been evaluated with regard to their skin hydrating and transepidermal water loss (TEWL)-modifying properties. Placebo samples were tested alongside the urea-containing ones. Two best performing moisturisers from the above were chosen for the second part of the study, in which sodium lauryl sulphate (SLS)-irritated skin was treated with both placebo and urea-containing samples. In addition to TEWL and skin hydration level, the erythema index (EI) was measured before, during and after the treatment. The results have shown that barrier-improving and hydrating abilities of urea are bi-directional and dependent on both the type of vehicle used for its delivery and the state of skin.

Topics: Adult; Double-Blind Method; Electric Impedance; Emulsions; Erythema; Female; Humans; Irritants; Permeability; Pharmaceutical Vehicles; Skin; Sodium Dodecyl Sulfate; Urea; Water

Cutaneous exposure to a variety of irritants has been extensively studied in recent years. Nevertheless, knowledge of the induction of irritant dermatitis, especially by mild irritants at low doses and for a short duration of exposure, is still incomplete.. To quantify the irritant effects and barrier disruption properties of ascorbic acid (ASC), acetic acid (ACA) and sodium hydroxide (NaOH), particularly in combination with an anionic detergent, sodium lauryl sulphate (SLS).. In a tandem repeated irritation test, the irritants were applied for 30 min twice daily for 4 days to the skin of the mid-back of 19 healthy volunteers of both sexes. We used bioengineering techniques for measurement of transepidermal water loss (TEWL) and skin colour reflectance, as well as visual scoring.. Repeated application of ASC and ACA caused a moderate increase in TEWL and erythema. The sequential application of ASC or ACA and SLS enhanced these effects. NaOH induced a strong reaction when applied both occlusively and nonocclusively as well as in combination with SLS, with an early onset of the inflammatory signs, leading to discontinuation of the application on the third day in most of the test fields. Notably, the irritant effect of NaOH was not as marked when applied sequentially with SLS.. Our results demonstrate that concurrent application of an anionic detergent and a mild acidic irritant can lead to disruption of the barrier function which, although not additive, is still considerable. The combined application of SLS and mild acids does not prevent SLS-induced irritation. Furthermore, we showed that NaOH in low concentrations may also act as a potent irritant but that its effect is not enhanced by SLS. The necessity of adequate skin protection and reduction of contact with substances that are potentially barrier disruptive and irritant, e.g. in the food industry, is emphasized, not only when handling detergents, but also when processing food products.

Topics: Acetic Acid; Adult; Ascorbic Acid; Dermatitis, Irritant; Drug Interactions; Erythema; Female; Food-Processing Industry; Fruit; Humans; Male; Middle Aged; Occupational Diseases; Patch Tests; Single-Blind Method; Sodium Dodecyl Sulfate; Sodium Hydroxide; Surface-Active Agents; Water Loss, Insensible

New therapeutic approaches have to be considered in the treatment of irritant contact dermatitis (ICD). Recently, phosphodiesterase 4 (PDE-4) inhibitors have been introduced as nonsteroidal, antiinflammatory agents. These agents inhibit the secretion of the cytokines thought to be involved in the pathogenesis of ICD. We investigated the effect of a new selective PDE-4 inhibitor (cipamfylline) in human models using single and repeated exposures to an irritant in a blind, randomized pilot study with healthy volunteers. We compared the effect of cipamfylline ointment with a strong corticosteroid (betamethasone-17-valerate) and with a placebo ointment.. Ten volunteers were patch tested at four investigation sites with sodium dodecyl sulphate (1%) for 24 h. In a model that simulates chronic damage, 11 volunteers were patch tested with sodium dodecyl sulphate (0.2%) for 4 h daily for four consecutive days. The investigation sites were treated once a day with the above-mentioned agents. One site was left untreated. We used erythema scoring, measurements of transepidermal water loss (TEWL) and several immunohistochemical markers for epidermal proliferation and differentiation.. Repeated application revealed that betamethasone-17-valerate caused a statistically significant reduction in erythema and TEWL compared to cipamfylline and placebo. We also observed a significant suppression of proliferating cells and cytokeratin 16 expression at sites treated with betamethasone compared to the other sites. In the model for acute ICD, no significant differences were seen between the investigated sites.. Our results show that betamethasone-17-valerate may modulate the response in ICD. In this human model of ICD we could not confirm the efficacy of cipamfylline. Clinical studies are needed before the effect of PDE-4 inhibitors in ICD can be refuted with certainty.

Topics: 3',5'-Cyclic-AMP Phosphodiesterases; Adult; Aged; Betamethasone Valerate; Cell Division; Cyclic Nucleotide Phosphodiesterases, Type 4; Dermatitis, Irritant; Dose-Response Relationship, Drug; Double-Blind Method; Enzyme Inhibitors; Erythema; Female; Glucocorticoids; Humans; Keratins; Male; Middle Aged; Pilot Projects; Sodium Dodecyl Sulfate; Surface-Active Agents; Water Loss, Insensible; Xanthines

Investigations of pruritogenic substances in humans have involved intradermal injections in normal skin; itching of inflamed skin has been little studied.. To develop an itch model with provocation of itch in experimentally inflamed skin as well as in normal skin, using subjects as self-controls.. In 32 non-atopic volunteers aged 21-30 years, the skin of five selected test sites on one volar forearm was pretreated for 24 h with large Finn chambers containing 1% sodium lauryl sulphate (SLS) used as a standard contact irritant to induce inflammation. Twenty microlitres of different pruritogenic substances [histamine, substance P, neurokinin A, neurokinin B, trypsin, platelet-activating factor (PAF) and serotonin] and saline as control were injected intradermally into the inflamed test sites and in corresponding non-treated sites on the opposite forearm. The test individuals scored itch intensity on a visual analogue scale for 20 min, and weal area was then measured. :. Histamine and substance P induced itch in both normal and inflamed skin compared with a saline reference. Neurokinin A, trypsin, PAF and serotonin only elicited itch in normal skin, and neurokinin B neither elicited itch in normal skin nor in inflamed skin. Itch was induced in normal and SLS-inflamed skin to a similar magnitude. However, weal area after histamine was significantly (P < 0.001) larger in inflamed skin when compared with normal skin.. Histamine and substance P elicited itch to the same degree in normal skin and inflamed skin pretreated with SLS despite a stronger weal response in inflamed skin. Mediators present in inflamed skin did not potentiate itch, a c-fibre-mediated neuronal response. The weal reaction is based on enhanced vascular permeability (protein extravasation). A greater skin perfusion in inflamed skin may therefore have increased the weal size. We propose an experimental model in humans for testing of itch involving both normal and inflamed skin. The model has the potential for use in evaluating new topical and systemic treatments of itch.

Topics: Adult; Dermatitis, Contact; Double-Blind Method; Edema; Erythema; Female; Histamine; Humans; Injections, Intradermal; Male; Neuropeptides; Pain; Pain Measurement; Pruritus; Severity of Illness Index; Sodium Dodecyl Sulfate

Moisturizers are widely used to treat irritant contact dermatitis (ICD). Their use is, however, not well-documented and standardized models for testing skin care products are needed to acquire documentation of their efficacy. The present study was undertaken to evaluate the effect of 6 commonly-used moisturizers on the recovery of irritated human skin. No commercial interests were involved in the study. 36 healthy volunteers had patch tests with SLS 0.5% applied on their forearms/upper arms for 24 h. After irritation of the skin, all volunteers had a moisturizer applied on one forearm/upper arm, respectively, 3 x daily for the following 5 days. The other forearm/upper arm served as an untreated control. Each moisturizer was tested on 12 volunteers and each volunteer tested 2 moisturizers at the same time. Evaluation was done on days 1, 3 and 8 by transepidermal water loss, electrical capacitance, laser Doppler flowmetry, DermaSpectrometry and clinical scoring. All 6 moisturizers were found to accelerate regeneration of the skin barrier function when compared to irritated non-treated skin. The most lipid-rich moisturizers improved barrier restoration more rapidly than the less lipid-rich moisturizers. We suggest this experimental model for further moisturizer efficacy testing.

Topics: Dermatitis, Contact; Electric Conductivity; Emollients; Erythema; Female; Humans; Irritants; Male; Regional Blood Flow; Severity of Illness Index; Single-Blind Method; Skin; Sodium Dodecyl Sulfate; Water Loss, Insensible

There remains much room for improvement in the accuracy of the patch test procedure. There has been a lack of knowledge regarding the possible relationship between the intensity of test reactions and the quality of the tape used to apply patch tests. Using different brands of tape, patches coated with 2 mg/cm2 sodium dodecyl sulfate (SLS) were applied for 24 h to the backs of 10 volunteers. The tape specimens varied in terms of manufacture, elasticity, adhesive strength, and water permeability. The intensity of patch test reactions, evaluated visually and objectively with both the high resolution laser Doppler perfusion imaging technique (HR-LDPI) and transepidermal water loss measurements (TEWL), varied significantly with the different brands of tape. Observed variations in the intensity of reactions to the patch tests could not be explained by any of the 4 tape parameters investigated. In order to attain optimal test quality in the future, both the tape and patches used in the testing system should be standardized and clearly labelled.

Topics: Adhesives; Adult; Bandages; Dermatitis, Allergic Contact; Erythema; Female; Humans; Laser-Doppler Flowmetry; Male; Middle Aged; Patch Tests; Regional Blood Flow; Severity of Illness Index; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents; Water Loss, Insensible

Evaluation of the irritant potential of new products or ingredients prior to human testing is generally performed in vivo on animals. However, according to the 6th amendment and following updates of the European Community directive on cosmetic products (93/35/EEC), animal testing will be banned when suitable substitutes will be available. To know whether in vitro tests for assessment of skin irritancy provide results approaching human conditions, comparisons have to be made between data deriving from in vitro tests and skin response in humans. The aim of our study was to assess the validity of the monolayer culture system of normal human keratinocytes as a model for the evaluation of the irritant effects of detergents, by comparing in vitro cell culture data to in vivo acute skin irritancy effects of cocamidopropyl betaine (CAPB), an amphoteric compound, Tween 20 (TW20) (polysorbate 20) and Tween 80 (TW80) (polysorbate 80), representing nonionic compounds, applied to the skin of 24 healthy volunteers at a concentration similar to that employed in commercial products. As parameters for cytotoxicity, cell proliferation, cell membrane integrity and cell metabolism were assessed by cell counts, thymidine incorporation, MTT conversion, and Neutral Red uptake. In order to increase the sensitivity of the in vivo evaluation, bioengineering methods for assessment of the effects of test products on the skin were employed. Whereas all 4 in vitro methods ranked the tensides according to their toxicity in the following order: CAPB>SLS>TW20>TW80, both in vivo methods agreed in identifying SLS as the most irritating substance. Moreover, as compared with the irritation potential on human skin, all 4 in vitro tests overestimated the toxicity of CAPB. This suggests that the keratinocyte monolayer cell culture technique cannot directly replace in vivo methods, and that data obtained by this method should be interpreted cautiously.

Topics: Adolescent; Adult; Betaine; Cell Survival; Cells, Cultured; Dermatitis, Allergic Contact; Dose-Response Relationship, Drug; Erythema; Excipients; Female; Humans; Keratinocytes; Middle Aged; Patch Tests; Polysorbates; Severity of Illness Index; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents; Water Loss, Insensible

The purpose of the present study was to compare 2 experimental models of moisturizer efficacy on the recovery of irritated skin on the hands and the volar forearms. 12 healthy volunteers had their hands immersed in sodium lauryl sulfate (SLS) 10 min 2x daily for 2 days, and at the same time the volunteers had patch tests with SLS (0.125%, 0.25% and 0.5%) applied on their forearms for 24 h. After irritation of the skin, the volunteers had a moisturizer applied on one arm/hand 3x daily for the following 9 days. The other arm/hand served as untreated control. Evaluation was done on days (D) 1, 3, 5, 8 and 12 by transepidermal water loss, electrical capacitance, laser Doppler flowmetry and DermaSpectrometry. Both models were found useful, and the moisturizer was found to accelerate regeneration of the skin barrier function in both the hands (D8, p<0.05) and the volar forearms (0.5% SLS, D5 and D8, p<0.01). When the forearm model is used in the present set-up, a relatively high concentration of SLS (>0.25%) should be used and evaluation measurements are best performed on D5-D8. The forearm model proved reliable and easy to handle and we suggest that this model is used in future studies on moisturizer evaluation.

Topics: Adult; Dermatitis, Irritant; Dose-Response Relationship, Drug; Electric Conductivity; Emollients; Erythema; Female; Forearm; Hand Dermatoses; Humans; Laser-Doppler Flowmetry; Male; Middle Aged; Patch Tests; Severity of Illness Index; Single-Blind Method; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents; Treatment Outcome; Water Loss, Insensible

Perfluoropolyethers (PFPEs) are non-reactive perfluorinated (no hydrogen atoms) liquid polymers that showed promise as ingredients of protective preparations in occupational dermatology.. The aim of this study was to investigate if oil-in-water (o/w) emulsions containing 0.5, 1.0, 2.0 and 4.0% PFPEs (molecular weight 6,250 D) prevent epidermal barrier disruption induced by a repetitive irritation test (RIT).. PFPE-containing o/w emulsions and the emulsion base alone were evaluated against a set of 4 irritants [10% sodium lauryl sulphate (SLS), 0.5% sodium hydroxide (NaOH), 15% lactic acid (LA), and undiluted toluene (TOL)] in the RIT. Ten subjects were tested on the paravertebral skin of the mid-back. Irritation was assessed by visual scoring, transepidermal water loss (TEWL) and colorimetry.. Both the emulsion base and all PFPE-containing preparations significantly suppressed irritation by SLS and NaOH. Against LA and TOL, only the 4% PFPE-containing preparation was significant as assessed by TEWL.. A 4% PFPE-containing o/w emulsion significantly inhibits irritation due to a wide spectrum of hydrophilic and lipophilic irritants. o/w emulsions with lower concentrations of PFPE are also effective against SLS and NaOH, but this is also true for the cream base alone. Therefore, further studies are necessary to evaluate if a minimum of 4% PFPE in the base provides additional benefit.

Topics: Caustics; Dermatitis, Irritant; Emulsions; Erythema; Ethers; Female; Fluorocarbons; Humans; Irritants; Lactic Acid; Male; Skin; Skin Pigmentation; Skin Tests; Sodium Dodecyl Sulfate; Sodium Hydroxide; Surface-Active Agents; Toluene; Water Loss, Insensible

Skin reactions to 4 toothpastes were tested in 19 healthy dental students in a double-blind study. The hypothesis was that common toothpaste brands with and without sodium lauryl sulfate (SLS) and triclosan and with different additives/emulgators differ in irritation potential. An occlusion test system on human skin was used. The toothpastes tested were A) Zendium (non-ionic detergent), B) Solidox F (SLS/polyethylene glycol), C) Colgate Total (triclosan/copolymer/SLS/propylene glycol), and D) Solidox G (triclosan/zinc citrate/SLS/polyethylene glycol). Toothpaste C was the greatest irritant, causing skin erythema in 16 of the 19 subjects, whereas toothpaste D gave no reactions. Toothpaste B provoked three reactions (two severe), whereas toothpaste A caused only one mild reaction. Although this study was carried out on skin and hence not directly applicable to the oral cavity, these and previous results may indicate that a toothpaste without propylene glycol and SLS may be preferred by susceptible persons.

Topics: Adult; Anti-Infective Agents, Local; Citrates; Dermatitis, Irritant; Disease Susceptibility; Double-Blind Method; Erythema; Female; Humans; Irritants; Male; Polyethylene Glycols; Skin; Skin Tests; Sodium Dodecyl Sulfate; Surface-Active Agents; Toothpastes; Triclosan; Zinc Compounds

In clinical practice, the cutaneous exposure to chemical irritants such as surfactants and topical drugs is frequent. Topical all-trans retinoic acid (RA) is often associated with irritation and induces epidermal changes similar to those produced by sodium lauryl sulphate (SLS). Using bioengineering techniques, e.g. assessing transepidermal water loss (TEWL), capacitance and chromametry, we investigated the variations of the skin response to SLS and RA and to both chemicals applied sequentially, allowing different time periods (from 1 h to 2 weeks) between applications of SLS and RA. Both chemicals caused irritation as assessed by visual scoring, but the values from the objective variables differed at different time periods. TEWL increased dramatically shortly after applying SLS but the increase was delayed after RA. After applying SLS, the capacitance generally decreased then returned to basal values; treatment with RA produced an overall increase. Only the results from chromametry were similar. After tandem application, the drugs were synergistic for all variables except capacitance, showing an antagonistic interaction for skin hydration. These results suggest that non-specific skin irritation profoundly reflects different mechanisms of action at tissue level. With sequential application, SLS injury modified the response to RA for at least 1 week after applying SLS. These late effects of detergents should be considered when studying irritant chemical interactions and in developing strategies for the management of occupational and other irritant dermatitis.

Topics: Adult; Drug Administration Schedule; Drug Eruptions; Drug Interactions; Erythema; Female; Galvanic Skin Response; Humans; Keratolytic Agents; Male; Patch Tests; Sodium Dodecyl Sulfate; Surface-Active Agents; Tretinoin; Water Loss, Insensible

The study was a single-centre, double-blind randomized, placebo-controlled within-subject comparison of 42 healthy volunteers. Occlusive patch test for 48 h was performed with solutions of 1 alpha,25(OH)2D3 (calcitriol), two vitamin D analogues (calcipotriol and KH 1060 (lexacalcitol)), all-trans retinoic acid and sodium lauryl sulphate (SLS) as reference irritant. Solution vehicles and an empty chamber was also included. Test evaluation was performed at day 2, day 3 and again on day 7. Test evaluation was based both on clinical scoring and on various non-invasive measuring methods. 1 alpha,25(OH)2D3, calcipotriol and KH 1060 all showed mild irritation in the concentrations tested. The number and severity of test reactions was found to be dose dependent based both on clinical scoring and on non-invasive measurements. Irritation of the vitamin D analogues mainly affected the vasculature with vasodilation and increased cutaneous blood flow. All-trans retinoic acid showed irritant reactions with some similarity to the tested vitamin D analogues; however, the reactions were more prolonged. Transepidermal water loss (TEWL) was affected neither after application of vitamin D analogues nor after application of all-trans retinoic acid and it was thus concluded that these substances are non-corrosive. SLS showed the known irritant mechanism with corrosion and increase in TEWL as the primary event.

Topics: Adult; Aged; Calcitriol; Dermatologic Agents; Double-Blind Method; Drug Eruptions; Erythema; Female; Humans; Male; Middle Aged; Patch Tests; Regional Blood Flow; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents; Tretinoin; Water Loss, Insensible

Previous studies on triclosan treatment of skin exposed to sodium lauryl sulphate (SLS) indicated a protective rôle of zinc and an irritant effect of propylene glycol (PG). The aim was hence to examine whether zinc or PG also may affect SLS-induced oral mucosal reactions, and also to test the influence of zinc in combination with triclosan. 15 healthy dental students participated in this double-blind crossover study performed in 2 experimental series. They were rinsing 2x daily with solutions containing (A) 1.5% SLS, (B) 1.5% SLS/0.5% zinc citrate and (C) 1.5% SLS/PG (1:8) in experiment 1, and (D) 1.5% SLS/0.15% triclosan/0.3% zinc citrate and (E) 1.5% SLS/0.15% triclosan in experiment 2. Clinical evaluation by 2 examiners of degree of erythema and oral mucosal desquamations was then performed. The critical micellar concentration was also determined. SLS and SLS/PG, which were not different in effect, evoked significantly more erythematous reactions than SLS/Tri/Zn. This solution was numerically but not statistically better than SLS/Tri, and the latter also did lead to significantly less erythema than SLS/PG. In conclusion, the present study revealed no irritation of the oral mucosa due to PG, whereas a protective effect of zinc as well as the anti-inflammatory effect of triclosan were confirmed.

Topics: Adult; Anti-Infective Agents, Local; Anti-Inflammatory Agents; Cross-Over Studies; Dermatologic Agents; Double-Blind Method; Erythema; Female; Humans; Irritants; Male; Mouth Diseases; Mouth Mucosa; Propylene Glycol; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents; Triclosan; Zinc

Topically applied all-trans retinoic acid (RA) is often associated with skin irritation. A detailed quantification of RA-induced functional changes in stratum corneum is, however, still limited. Using non-invasive bioengineering techniques of measurements of transepidermal water loss (TEWL), stratum corneum hydration and cutaneous blood flow (CBF), we quantified the irritant effects of 0.05% and 0.1% RA in ethanol on normal skin compared with 1% sodium lauryl sulphate (SLS) in water as a model irritant in a 24-h occlusive patch-test assay. Additionally, in order to document data possibly related to the mechanism of action, skin responses to both compounds applied in tandem was also investigated over 18 days. The extent of the irritant response to 0.05 and 0.1% RA, respectively, were similar, implying analogous irritation potency. While RA caused more intense scaling than SLS, other skin responses to RA were significantly weaker than those due to SLS. An increase in TEWL, on day 7, in RA-exposed sites indicates a secondary delayed impairment of the stratum corneum (SC) barrier. In a tandem-design assay, pretreatment with RA appeared to reduce the irritant effects of SLS on SC hydration and CBF. In contrast, pre-exposure to SLS showed a synergestic response in erythema, scaling and TEWL. Our results demonstrate that RA, like SLS, is capable of impairing SC water barrier function, which may be responsible, in part, for the irritation associated with its topical use. However, the distinctive biological responses to these compounds suggest a different mode of action of RA and SLS. In addition, the precise reason for the unique results observed in the tandem-design assays is not clear.

Topics: Administration, Topical; Adult; Blood Flow Velocity; Cross-Over Studies; Drug Eruptions; Erythema; Female; Humans; Keratolytic Agents; Male; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents; Tretinoin

Exposure to water and detergents is an important factor for development of irritant contact dermatitis. The aim of the present study was to investigate the effect of temperature on the damaging effects of water and detergents on the skin. Twenty healthy volunteers participated in the study. Ten participants had right and left forearms immersed into a detergent (soap) solution for 2 days twice daily for 10 min. Another 10 participants had both forearms immersed into sterile water. Right and left forearms were randomized to immersion into 20 degrees C and 40 degrees C solutions, respectively. Reactions were evaluated clinically, and by measurement of transepidermal water loss, electrical capacitance and erythema. Immersions into 40 degrees C sodium lauryl sulphate solution caused significantly increased transepidermal water loss as compared to immersion into 20 degrees C sodium lauryl sulphate solution. Electrical capacitance and erythema were not significantly influenced by temperature. Immersion into water caused no significant changes in any observed parameter. Water temperature influences the irritant capacity of a detergent. Change of temperature may be a simple but important means for prevention of irritant contact dermatitis.

Topics: Adult; Dermatitis, Irritant; Detergents; Electric Impedance; Erythema; Female; Forearm; Humans; Immersion; Irritants; Male; Middle Aged; Skin; Soaps; Sodium Dodecyl Sulfate; Temperature; Water; Water Loss, Insensible

Calcipotriol, a vitamin D analogue utilized for psoriasis, has irritation as its most frequent reported adverse event. However, studies on its irritant properties in humans have produced conflicting data. This study evaluates the effect of calcipotriol on stratum corneum barrier function, hydration and cell turnover in healthy volunteers, compared with sodium lauryl sulphate (SLS) as a model irritant. Calcipotriol 0.005% ointment and 1% aqueous SLS solution were applied for 60 min once daily for 2 weeks (5 consecutive days weekly) on untreated and on dansyl-chloride-labelled skin. Irritant responses were documented by visual scoring and by measurement of the transepidermal water loss (TEWL) and stratum corneum hydration (electrical capacitance), until day 18. Stratum corneum turnover time (SCTT) was the time in days between staining (day 0) and the disappearance of dansyl fluorescence. SLS caused more erythema, scaling, and a significant TEWL increase for 18 days. In contrast, calcipotriol induced erythema, and slightly but significantly increased TEWL on day 11 only, as compared with the vehicle control (P < 0.05). SLS, but not calcipotriol, caused skin dryness from day 4 to day 18. The shortest SCTT was obtained at SLS-exposed sites (11.2 +/- 0.7 days: mean +/- SD). Calcipotriol significantly shortened SCTT (16.3 +/- 1.1 days) when compared with its vehicle. Compared with the skin irritation induced by SLS, under these test conditions, calcipotriol is a far weaker irritant on normal human skin. In addition, calcipotriol accelerates stratum corneum turnover to a significantly greater extent than its vehicle.

Topics: Adult; Calcitriol; Cell Division; Dermatologic Agents; Drug Eruptions; Epidermis; Erythema; Female; Galvanic Skin Response; Humans; Male; Sodium Dodecyl Sulfate; Water Loss, Insensible

Topical corticosteroids are frequently used in the treatment of irritant contact dermatitis (ICD). The efficacy of this treatment has, however, not been thoroughly established, and experimental studies on the topic have provided conflicting results. The aim of the present study was to evaluate the effect of potent topical corticosteroids on experimentally-induced irritant skin reactions in a double-blind, vehicle-controlled study. 16 healthy volunteers had sodium lauryl sulfate patch tests symmetrically applied to the upper arms. After removal of patch tests, a potent topical corticosteroid (betamethasone-17-valerate) was applied to the irritant skin reaction on one arm, while the corresponding vehicle was applied to the irritant skin reaction on the opposite arm 2x daily for 7 days. Reactions were evaluated by measurement of transepidermal water loss (TEWL) and erythema. After 7 days, statistically significant lower values of TEWL and erythema were found in corticosteroid-treated, compared to the vehicle-treated, skin reactions. The results indicate that topical corticosteroids improve healing of ICD.

Topics: Administration, Topical; Adult; Anti-Inflammatory Agents; Dermatitis, Contact; Dermatitis, Irritant; Double-Blind Method; Eczema; Erythema; Female; Glucocorticoids; Humans; Male; Middle Aged; Patch Tests; Skin Absorption; Sodium Dodecyl Sulfate; Treatment Outcome; Water Loss, Insensible

Surfactant-induced irritant reactions may be elicited by several endogenous and exogenous factors. Among these, surfactant concentration, and duration and frequency of exposure play important rôles. The study focuses on the influence of water temperature in determining damage of the skin barrier. 10 subjects of both sexes entered the study. 4 areas (4 x 4 cm2) were randomly selected on the volar forearm and were treated with a daily open application of 5% sodium lauryl sulphate for 4 days. The solutions were at 3 temperatures: 4 degrees, 20 degrees and 40 degrees C. One site served as untreated control. On the 5th day, skin irritation was evaluated using transepidermal water loss (TEWL) measurements, erythema (a* value), skin reflectance (L* value), hydration (capacitance) and desquamation (stripping). The results show a significant effect of the solution's temperature in determining skin irritation (P < 0.001). Skin damage was higher in sites treated with warmer temperatures and a highly significant correlation (P < 0.001) between irritation and temperature was found. In conclusion, the study shows that water temperature during washing has an important effect on the onset of irritant contact dermatitis.

Topics: Adult; Analysis of Variance; Body Water; Dermatitis, Irritant; Detergents; Epidermis; Erythema; Female; Forearm; Humans; Male; Sodium Dodecyl Sulfate; Surface-Active Agents; Temperature; Water; Water Loss, Insensible

Variable types of skin irritation were induced in 8 human female volunteers, ranging from subclinical to visible erythema with slight oedema. Skin reactions were graded clinically and objectively using transepidermal water loss (TEWL), laser Doppler flowmetry (LDF) and improved reflectance spectroscopy. This last technique enables separation of in vivo erythemas into relatively deoxygenated (venous--deoxy hem) and oxygenated (arterial--oxy hem) haemoglobin components. Compared to uninvolved skin, an empty patch increased oxy hem by 197% +/- 121% (p < 0.05). Exposure to vehicles also changes skin biophysics. At sodium lauryl sulfate (SLS) and hydrochloric acid (HCl) exposed sites, a linear correlation between concentration and oxy hem, LDF and TEWL was found. These chemicals predominantly increased TEWL values. Nonanoic acid (NON) and imipramine (IMI) also raised oxy hem, LDF and TEWL values linearly at increasing concentrations. Although IMI 2.5% clinically was graded as a type ++ response, no significant increase in TEWL was found. The improved reflectance spectroscopic technique proved valid in skin irritation studies, with a higher sensitivity than laser Doppler flowmetry, and allowed irritant vascular reactions to be discriminated into arterial and venous components. Furthermore, our observations clearly demonstrate that clinically indistinguishable skin irritation reactions induce significantly different changes in barrier function (disruption) and vascular status.

Topics: Adult; Biomedical Engineering; Dermatitis, Irritant; Edema; Erythema; Fatty Acids; Female; Hemoglobins; Humans; Hydrochloric Acid; Imipramine; Irritants; Laser-Doppler Flowmetry; Middle Aged; Oxyhemoglobins; Skin; Sodium Dodecyl Sulfate; Spectrophotometry; Water Loss, Insensible

1. The limitations of the Draize rabbit skin irritation test for hazard evaluation for man are widely documented. Nevertheless it remains the prescribed method for determining acute skin irritations hazard. 2. While the use of human testing for risk assessment of irritants is well established, the use of predictive testing in man for hazard identification has not been explored widely, and this is the object of the research programme. 3. The experiment described in this report evaluates the sensitivity of four patch testing systems (Finn chamber, Hill Top patch, Van der Bend chamber, and Webril patch) using a total of six irritant substances. 4. Following preliminary range-finding experiments, test materials were applied to the upper outer arm for up to 4 h. Assessments were performed immediately after patch removal and at 1, 24, 48, and 72 h. 5. Webril and Hill Top patches generated the greatest levels of response, although responses with Finn and Van der Bend were observed. Hill Top patches are recommended for future development work. 6. The use of very small preliminary panels to predict the effects in larger panels using different volunteers was only of limited value as each volunteer was found to have different irritant thresholds.

Topics: Acetates; Acetic Acid; Adolescent; Adult; Aged; Cetrimonium Compounds; Cyclohexenes; Edema; Erythema; Ethanolamines; Female; Humans; Irritants; Limonene; Male; Middle Aged; Patch Tests; Risk Assessment; Sodium Dodecyl Sulfate; Sodium Hydroxide; Terpenes; Time Factors

Topics: Adult; Benzenesulfonates; Body Water; Castor Oil; Dermatitis, Irritant; Drug Combinations; Epidermis; Erythema; Female; Humans; Hydrogen-Ion Concentration; Laser-Doppler Flowmetry; Lipids; Male; Ointments; Permeability; Regional Blood Flow; Sebum; Siloxanes; Skin; Sodium Dodecyl Sulfate; Stearates; Waxes

The irritation potential of surfactants and body cleansing products was determined by evaluating the removal of dansyl chloride from the skin. Dilute solutions (2% active ingredient, w/v) of surfactants and soap extract fluorescence from the skin within 30 min. This is probably a physicochemical effect as it is too rapid to be due to a modification of epidermal cell turnover rate. Such an extraction of the fluorescent dye occurs without any clinical sign of irritation. However, it may represent an early phase of the skin irritation process, because it is related to the ranking of irritant products as determined by other assessment methods.

Topics: Betaine; Body Water; Dansyl Compounds; Dermatitis, Irritant; Detergents; Erythema; Fluorescence; Humans; Patch Tests; Polysorbates; Quaternary Ammonium Compounds; Reproducibility of Results; Skin; Skin Diseases; Soaps; Sodium Dodecyl Sulfate; Staining and Labeling; Surface-Active Agents

The effects of softened fabrics on the skin were evaluated by a forearm wet and dry test, under conditions simulating real-life skin contact with fabrics. 15 volunteers with sensitive skin according to dermatological assessment and their own recognition entered a double-blind 12 day, 3 sessions per day, forearm wetting and drying test, using cotton fabrics washed with a powder detergent and softened or not with a liquid fabric conditioner. To simulate conditions of skin damage, a dilute solution of sodium lauryl sulfate was applied under patch to the forearm before the start of the study. Skin effects were evaluated by visual grading (redness, dryness and smoothness), by noninvasive skin stripping and measuring of Chroma C* (squamometry), and by instrumental measurements (capacitance, transepidermal water loss, and colorimetry). Both the unsoftened and softened fabrics induced no deleterious effects on control or previously irritated skin. Furthermore, a mild beneficial effect was observed with the softened fabrics, particularly on previously irritated skin. The study findings suggest that softened fabrics may exert a reduced frictional effect on the skin.

Topics: Adult; Colorimetry; Dermatitis, Contact; Dermatitis, Irritant; Detergents; Double-Blind Method; Epidermis; Erythema; Gossypium; Hand Dermatoses; Humans; Laundering; Middle Aged; Patch Tests; Sodium Dodecyl Sulfate; Textiles; Water Loss, Insensible

Digestive enzymes in faeces have been reported to possess skin irritation potential. The present study was designed to investigate the in vivo irritant potentials of faecal concentrations of proteolytic and lipolytic digestive enzymes in bile salt mixtures. In a 21-day cumulative irritation assay, clinical evaluation and noninvasive bioengineering techniques were used. 5 days occlusive exposure to phosphate buffer (pH = 8) caused no visual skin damage but reflectance spectroscopy demonstrated significant vasodilation (p < 0.01) and increases in transepidermal water loss (TEWL) and skin pH were also observed (p < 0.01). These increases were still present at days 12 and 19. Occlusive exposure to physiologic concentrations of faecal enzymes resulted in significant visual and objective scores at day 5, 12, and 19, with increased readings as a function of exposure time (p < 0.01). The enzyme mixture containing lipase caused delayed onset of skin erythema and epidermal barrier disruption compared to elastase and chymotrypsin containing solutions. Prolonged occlusive exposure to digestive enzymes in faecal concentrations caused severe skin erythema and epidermal barrier disruption in a human model, suggesting a possible etiologic role of digestive enzymes in perianal, circumstomal or diaper dermatitis.

Topics: Adult; Chenodeoxycholic Acid; Cholic Acid; Cholic Acids; Chymotrypsin; Deoxycholic Acid; Dermatitis, Irritant; Erythema; Feces; Female; Humans; Hydrogen-Ion Concentration; Irritants; Lipase; Lithocholic Acid; Male; Middle Aged; Pancreatic Elastase; Skin; Skin Physiological Phenomena; Sodium Dodecyl Sulfate; Trypsin; Water Loss, Insensible

Although the induction of irritant dermatitis by surfactants has been extensively studied in recent years, our understanding of the repair phase of irritant dermatitis is limited.. We investigated qualitative and quantitative differences in surfactant-induced irritant skin reactions from short-term exposure to three structurally different surfactants.. Sodium lauryl sulfate (SLS), dodecyl trimethyl ammonium bromide (DTAB), and potassium soap were the model irritants. Surfactant solutions (0.5%) were applied for 24 hours to the volar aspect of the forearm of 11 volunteers. Irritant reactions were assessed until complete healing was indicated by visual assessment and by various aspects of skin function, that is, transepidermal water loss (TEWL), erythema (skin color reflectance), and stratum that is, transepidermal water loss (TEWL), erythema (skin color reflectance), and stratum corneum hydration (electrical capacitance).. SLS and DTAB induced similar degrees of erythema, whereas SLS induced significantly higher TEWL increase. Although both erythema and TEWL were highest 1 hour after exposure to surfactants, skin dryness was a symptom with delayed onset, justifying the long observation period in this study. Minimum hydration values were measured as late as 7 days after surfactant exposure. Dryness was significantly more pronounced in areas exposed to SLS than in areas exposed to DTAB. Complete repair of the irritant reaction induced by either SLS or DTAB was achieved 17 days after surfactant exposure. Stratum corneum hydration was the last feature to return to baseline values. Potassium soap did not significantly influence any skin function.. We emphasize the importance of extended periods needed before a patient with irritant contact dermatitis can be reexposed to irritant substances. The evaluation of the irritation potential of diverse surfactants depended significantly on the feature (erythema vs hydration and TEWL) measured.

Topics: Adult; Dermatitis, Irritant; Detergents; Double-Blind Method; Erythema; Galvanic Skin Response; Humans; Lipids; Middle Aged; Quaternary Ammonium Compounds; Skin; Skin Physiological Phenomena; Soaps; Sodium Dodecyl Sulfate; Surface-Active Agents; Time Factors; Water Loss, Insensible; Wound Healing

Acute topical treatment of human skin with retinoic acid (RA) results in a pleiotropic response, some aspects of which are mimicked by non-specific irritants. To identify reliable cutaneous markers of retinoid action, it is important to determine which aspects of this response are specifically due to the presence of RA. We have previously demonstrated a rapid and pronounced increase in steady-state cellular RA-binding protein II (CRABP-II)mRNA levels after topical RA treatment. Here we characterize the dose dependence and kinetics of this response, and compare the effects of a well-known irritant, sodium dodecylsulfate (SDS), to those of RA and its vehicle. The induction of CRABP-II mRNA in response to 0.1% RA cream was maximal by 16 h (elevenfold relative to untreated skin), and persisted at near-maximal levels (eight-fold) for up to 4 d. RA was potent in eliciting this response, as approximately half-maximal stimulation was observed after 16 h of treatment with 0.001% RA. Treatment for 4 d with 0.1% RA cream versus 2% SDS in RA vehicle resulted in nearly identical levels of cutaneous erythema, spongiosis, and epidermal thickening. However, the CRABP-II mRNA response to 2% SDS was no greater than that observed in response to vehicle alone (2.9 times relative to occluded skin control at 4 d). SDS also had no effect upon either CRABP-II or RAR-beta mRNA levels in quiescent human dermal fibroblasts in vitro, whereas RA elicited both responses at 1000-times lower concentrations than SDS. Taken together, these data identify the CRABP-II mRNA response as a reliable, rapid, and selective marker for retinoid activity in human skin.

Topics: Carrier Proteins; Dose-Response Relationship, Drug; Erythema; Fibroblasts; Humans; Receptors, Retinoic Acid; RNA, Messenger; Skin; Skin Physiological Phenomena; Sodium Dodecyl Sulfate; Time Factors; Transcription, Genetic; Tretinoin

Topics: Adult; Colorimetry; Erythema; Female; Humans; Reference Values; Sodium Dodecyl Sulfate

The efficacy of topically applied corticosteroid formulations of different potencies on irritant skin reactions was assessed in human beings. Chronic irritant contact dermatitis was produced by repeated application of a low-molarity sodium lauryl sulfate solution. Neither corticoid nor vehicle inhibited visible response to the irritant. Barrier function, as measured by transepidermal water loss, was impaired. The corticoid formulations and the vehicles did not significantly influence barrier function. These data raise the question of the value of certain topical corticoids and vehicles in chronic irritant contact dermatitis when the irritant is not removed.

Topics: Administration, Topical; Adrenal Cortex Hormones; Adult; Aged; Dermatitis, Contact; Double-Blind Method; Drug Evaluation; Erythema; Female; Humans; Irritants; Male; Middle Aged; Pharmaceutical Vehicles; Sodium Dodecyl Sulfate; Water Loss, Insensible

Alcohol-based disinfectants and detergents are common workplace factors for irritant contact dermatitis (ICD). Though occlusion and water are relevant co-exposures, the tandem effects of occlusion and sequential exposure to alcohols and detergents have not been studied. We therefore investigated the combined effects of occlusion with water and repeated exposure to n-propanol and/or sodium lauryl sulphate (SLS) in an occlusion-modified tandem irritation test. The outcomes included visual scoring, measurement of erythema, transepidermal water loss, capacitance and natural moisturizing factor (NMF) levels. Occlusion abrogated the skin barrier function and significantly enhanced the irritant-induced barrier damaging effects. The NMF levels of all irritant-exposed fields decreased significantly compared with the non-exposed fields; occlusion enhanced the decrease in NMF. Although SLS exerted more pronounced effects on the measured parameters, the barrier function impairment and NMF decrease after exposure to n-propanol in workplace-relevant concentrations, found in the study, confirm the significance of short-chain aliphatic alcohols for occupational ICD.

Topics: 1-Propanol; Adult; Aged; Chromatography, High Pressure Liquid; Dermatitis, Irritant; Dermatitis, Occupational; Erythema; Female; Humans; Irritants; Male; Middle Aged; Skin Tests; Sodium Dodecyl Sulfate; Water Loss, Insensible

Present study was conducted to evaluate the dermatoprotective effects of plant extracts (Ficus religiosa, Ficus benghalensis, and Ficus racemosa) against known irritants such as sodium dodecyl sulfate (SDS), atrazine, and petrol.. The study was conducted in adult male rabbits. Ethanol extracts of plants were obtained through Soxhlet. All irritants and Ficus extracts were topically applied to the backs of rabbits daily for 4 days, while pure ethanol served as control. Skin was examined after 24, 48, and 96 h for erythema. Skin biopsies were taken on 5th day for microscopic examination.. Erythema produced by irritants reduced significantly with the simultaneous application of Ficus extracts. The mean ± SEM epidermal thickness (micrometer) with SDS was 45.40 ± 1.89, F. religiosa + SDS was 18.60 ± 0.51, F. benghalensis + SDS was 18.40 ± 0.25, F. racemosa + SDS was 18.80 ± 0.37, and mixture of three Ficus species + SDS was 16.80 ± 0.37. Similar findings were revealed after using plant extracts with atrazine and petrol. The mean ± SEM epidermal layer count for SDS was 3.60 ± 0.25, atrazine was 3.40 ± 0.25, petrol was 3.40 ± 0.25, and ethanol (control) was 1.00 ± 0.20. This count reduced to 1.20 ± 0.20 for three Ficus species + SDS, 1.40 ± 0.25 for Ficus species + atrazine, and 1.40 ± 0.25 for Ficus species + petrol.. Ficus species demonstrated the potential to block the dermatotoxic effects of topical irritants and could be used successfully to prevent skin toxicity.

Topics: Animals; Atrazine; Dermotoxins; Erythema; Ficus; Gasoline; Male; Plant Extracts; Rabbits; Skin; Sodium Dodecyl Sulfate

To confirm the effect of human urine in the treatment of wounds, burns and irritation.. The study was conducted at Bahauddin Zakariya University, Multan, in November 2013 and comprised 15 rabbits of either gender. Irritation was induced by clockwise frictional movement of fine sandpaper to the ear of the rabbits. The counter-irritant activity was determined by calculating the mean decrease in redness and erythema. A group of 3 rabbits each was used while experimenting with the main assay every time the concentration of irritants was increased. The ear treated with distilled water was used as a control. Sodium lauryl sulfate irritation model was also applied and the counter-irritant activity was evaluated. One-way analysis of variance followed by Bonferroni test were used for statistical analysis.. The mean weight of the 15 rabbits was 1.5+/-SD kg. Urine (50 and 100µl) showed excellent counter-irritant activity when compared with control and standard dexamethasone. Both the doses showed counter-irritant activity, ranging between 76.84% and 95.68% in the sandpaper model, and 68.90% and 93.68% in the sodium lauryl sulfate model.. Human urine countered the effect of irritation in experimental animals and can be an alternative way of countering irritation.

Topics: Animals; Burns; Dexamethasone; Erythema; Humans; Rabbits; Sodium Dodecyl Sulfate; Urine; Wounds and Injuries

Tranexamic acid (TA) is a traditional plasmin inhibitor, and its role in the renovation of damaged skin has become the topic of a lot of research. The aim of this study is to determine whether TA could repair the skin barrier by means of tight intercellular junctions.. Two kinds of damaged skin models were set up and subjected to repeated application of sodium lauryl sulfate and irradiation of ultraviolet B. Through bioengineering technology and immunohistochemistry tests, TA-induced changes in skin were detected.. After 1, 3, 7, and 14 days of application, TA can significantly accelerate barrier recovery and decrease the melanin index values of ultraviolet B irritation skin. The mean optic density of occludin from TA treatment is higher than from self-repair.. These experiments suggest that TA can accelerate skin barrier recovery and upregulate occludin induced by physicochemical damages of human skin, but it is advisable to perform more research on the upregulation of occludin in molecular mechanism in the future.

Topics: Adult; Aged; Antifibrinolytic Agents; Erythema; Female; Humans; Male; Melanins; Middle Aged; Occludin; Radiation Injuries; Skin; Skin Physiological Phenomena; Sodium Dodecyl Sulfate; Tight Junctions; Tranexamic Acid; Ultraviolet Rays; Up-Regulation; Wound Healing; Young Adult

Dermal exposure to alkaline agents may lead to skin barrier damage and irritant contact dermatitis. The objective of this study was to investigate the effects of cumulative exposure to 0.5% sodium lauryl sulphate (SLS) and 0.15% NaOH on the barrier function and natural moisturising factor (NMF) levels in atopic dermatitis and healthy volunteers with known filaggrin genotype. The skin response was monitored by measurement of erythema and transepidermal water loss. The stratum corneum NMF levels were determined by high-performance liquid chromatography. Repeated exposure to 0.5% SLS and/or 0.15% NaOH in atopic dermatitis resulted in more severe impairment of the skin barrier function. Cumulative exposure to the irritants reduced significantly NMF in both the atopic and healthy controls group. The pronounced decrease of NMF after repeated single and sequential irritant exposure may be a pathogenetically relevant factor for development of chronic irritant contact dermatitis in both healthy and atopic individuals.

Topics: Administration, Cutaneous; Adult; Aged; Case-Control Studies; Dermatitis, Atopic; Dermatitis, Irritant; Erythema; Female; Filaggrin Proteins; Genetic Predisposition to Disease; Humans; Hydrogen-Ion Concentration; Intermediate Filament Proteins; Irritants; Male; Middle Aged; Mutation; Phenotype; Risk Factors; Skin; Skin Irritancy Tests; Sodium Dodecyl Sulfate; Sodium Hydroxide; Time Factors; Water; Water Loss, Insensible; Young Adult

Sodium laureth sulphate (SLES) is an anionic detergent, which has been used globally for personal care products because of its mildness and good foaming ability. However, SLES is somewhat invasive and stimulatory to the skin, and many consumers with sensitive skin desire milder detergents for daily use skin cleansers. We enhanced the mildness of SLES by formulating it with sodium laureth carboxylate (AEC) and lauryl glucoside (LG).. In skin soak tests, 5% detergent solutions were applied to the forearms of 10 Japanese healthy volunteers for 30 min followed by washing with tap water once a day for 4 days. Twenty-four hours after the last treatment, cutaneous capacitance measurements and visual analyses were performed. In a controlled usage study, 16 Japanese healthy volunteers used the test body cleanser for 4 weeks. Assessment of efficacy and mildness was conducted prior to the start of the study and at the end of week 4 by cutaneous conductance, dermoscopic evaluation of the stratum corneum and visual assessment by a dermatologist.. In soak tests, cutaneous capacitance was significantly decreased on the soap-treated region and on the SLES-treated region. No significant decrease was identified on the SLES/AEC/LG-treated region with less induction of erythema or dryness. In the controlled usage study, no significant changes in cutaneous conductance or texture or damage of corneocytes on the forearm and lower thigh were found. However, visual assessment revealed a significant decrease in scaling and erythema on the lower thigh after 4 weeks of usage with an improvement of the discomfort of the consumer. The favourability rating of this formulated detergent in several questionnaire items was very good.. The newly formulated skin cleanser with the combination of anionic surfactants SLES and AEC and the non-ionic surfactant LG provides a mild surfactant with a satisfactory cleansing activity for body washing.

Topics: Carboxylic Acids; Erythema; Galvanic Skin Response; Glucosides; Humans; Japan; Male; Skin; Soaps; Sodium Dodecyl Sulfate; Statistics, Nonparametric; Surveys and Questionnaires; Water Loss, Insensible

Skin protective creams (PCs) are used widely in industrial work environments to prevent irritant contact dermatitis. However, workplace studies remain equivocal in terms of their effectiveness, which may be partly owing to whether the PC remains on the skin.. To assess the practicability of using skin occlusion testing in a workplace as a method to determine whether PCs applied under controlled conditions can reduce skin damage against known irritants. This study also compares two methods of skin evaluation: clinical dermatological assessment and bioengineering techniques.. Daily occlusion testing for 1 h (over two consecutive weeks) was conducted in an engineering company on the volar forearm of 21 healthy volunteer engineers with sodium lauryl sulfate (SLS) and a PC that was used on site. The engineers conducted their normal work activities during the occlusion testing period. The skin areas tested were assessed using transepidermal water loss (TEWL), Chroma Meter and by visual dermatological scoring.. Testing with PC and SLS together showed that PC does not prevent irritant contact dermatitis but significantly reduced skin damage compared with SLS alone (P < 0.01). The changes in skin were evident earlier with the biophysical measurements when compared with the dermatological assessment.. Occlusion testing is a useful method for assessing the potential effectiveness of protective creams and can be used in a workplace without affecting work practices. TEWL and the Chroma Meter provide useful objective information and should be used in combination with dermatological examinations.

Topics: Administration, Cutaneous; Adult; Anti-Inflammatory Agents; Dermatitis, Irritant; Dermatitis, Occupational; Dermatologic Agents; Drug Combinations; Drug Interactions; Erythema; Humans; Humidity; Kaolin; Male; Middle Aged; Oils; Patch Tests; Skin Cream; Sodium Dodecyl Sulfate; Surface-Active Agents; Temperature; Water Loss, Insensible; Waxes; Workplace

The barrier perturbation pattern and molecular markers of inflammation upon tandem repeated irritation in chronologically aged skin have not been previously studied.. We aimed to investigate the barrier impairment kinetic and in vivo cytokine profile following sequential irritation with sodium lauryl sulfate (SLS) and undiluted toluene (Tol) in aged compared with young skin.. Four fields on the volar forearm of healthy aged and young volunteers (median age, respectively, 63.9 and 32.6 years) were sequentially exposed to 0.5% SLS and undiluted toluene in a controlled tandem repeated irritation test; an adjacent nontreated field served as control. The permeability barrier function was monitored by repeated measurements of transepidermal water loss (TEWL), capacitance and erythema every 24 h up to 96 h. The stratum corneum cytokines were harvested by sequential tape stripping and quantified by multiplex bead array and enzyme-linked immunosorbent assay.. Compared with young skin, aged skin was characterized by delayed and/or less pronounced alterations in the visual irritation score, TEWL, chromametry a*-value and capacitance, assessed by the respective Δ-values for each parameter and monitoring time point. In both groups, exposure to SLS/SLS, SLS/Tol and Tol/SLS resulted in decreased interleukin (IL)-1α levels, whereas the application of Tol/Tol induced an increase in IL-1α. Furthermore, decreased IL-1 receptor antagonist (IL-1RA) levels and a lower IL-1RA/IL-1α ratio were found following repeated exposure to the irritants.. Our results provide evidence for selective alterations in the cytokine profile and distinct barrier impairment kinetic following tandem repeated irritation with SLS and Tol in aged compared with young skin in vivo.

Topics: Adult; Aged; Body Water; Cytokines; Dermatitis, Irritant; Enzyme-Linked Immunosorbent Assay; Epidermis; Erythema; Female; Humans; Interleukin-1alpha; Male; Middle Aged; Receptors, Interleukin-1 Type I; Skin; Skin Aging; Sodium Dodecyl Sulfate; Solvents; Surface-Active Agents; Toluene; Young Adult

In the investigation and management of skin disease, various testing protocols are of importance. The extent to which clinical judgments and decisions on therapy are supported by the performance of such testing can be affected negatively by the lack of time and resources for the performance of tests. In the present study, the possibility of utilizing self-reporting by subjects is investigated. Determination of irritation threshold for sodium lauryl sulphate (SLS) and minimal erythema dose for ultraviolet B were chosen as suitable self-reading protocols. Test reading by 26 subjects instructed in "present" or "absent" reporting of test reactions were compared to trained observer reading. Absolute agreement was found in 76.9 percent of the SLS reactions and in 85 percent of the UVB reactions. Weighted Kappa for the agreement between observations showed values of 0.76 for the SLS reactions and 0.83 for UVB reactions. We conclude that use of the protocols here studied, and other test protocols modified to accommodate a binomial assessment outcome ("+" or "-"), could well lead to an increase in the performance of skin testing. This could be a qualitative advantage for diagnosis and management of skin diseases. Additionally, population studies and even prevention initiatives could be facilitated.

Topics: Adult; Clinical Medicine; Differential Threshold; Erythema; Female; Humans; Male; Observer Variation; Patch Tests; Patients; Reproducibility of Results; Research; Skin; Skin Diseases; Skin Irritancy Tests; Skin Tests; Sodium Dodecyl Sulfate; Ultraviolet Rays; Young Adult

Alitretinoin is a new drug for systemic treatment of chronic hand eczema. Previous functional tests of skin topically treated with retinoids have indicated impaired skin barrier function, but no data are available on barrier parameters after systemic alitretinoin treatment. To investigate the effect of systemic alitretinoin on skin barrier function and response to irritants, a secondary objective was to determine if changes occur in the lipid profile of stratum corneum after treatment with systemic alitretinoin. We conducted an open clinical intervention study on eight people ascribed to systemic alitretinoin treatment. The criteria for being ascribed to alitretinoin were chronic hand eczema and insufficient therapeutic response to potent topical corticosteroids. Before initiation and after 2 months of systemic treatment with 30 mg alitretinoin, a challenge with sodium lauryl sulphate (SLS) was performed on the volar forearm and evaluated by trans-epidermal water loss (TEWL), erythema, and a cyanoacrylate skin sample was obtained for lipid analysis. We found no significant changes in response to SLS irritation as evaluated by TEWL and erythema, after treatment with alitretinoin for 2 months. No significant changes in stratum corneum lipids were found after 2 months of treatment. In conclusion, systemic alitretinoin does not influence skin susceptibility to irritants or the ceramide profile of stratum corneum.

Topics: Alitretinoin; Ceramides; Chronic Disease; Disease Progression; Eczema; Epidermis; Erythema; Humans; Irritants; Retinoids; Sodium Dodecyl Sulfate; Tretinoin; Water Loss, Insensible

Chronic irritant hand dermatitis is an issue for healthcare workers and may negatively impact infection control.. We examined the effects of a G to A transition at position -308 on the tumour necrosis factor-α (TNF-α) gene on chronically damaged skin of healthcare workers during exposure and recovery from repetitive hand hygiene, after intensive treatment, and on the irritant response in normal skin.. In 68 healthcare workers with irritant hand dermatitis, we genotyped TNF-α-308 and measured the epidermal response via quantitative digital imaging, erythema, dryness, and barrier integrity.. Excess hand erythema decreased with hand hygiene exposure and increased during time off for AA/GA genotypes, but had opposite effects for GG. AA/GA had smaller reductions in dryness with lotion treatment and larger reductions in excess erythema than GG. The atopic diathesis and heightened neurosensory irritation resulting from water and lactic acid significantly influenced the responses. Repeated exposure to water and sodium lauryl sulfate (0.05, 0.1%) produced higher erythema in normal skin for AA/GA than for GG.. This study provides evidence that the TNF-α polymorphism at -308 and an atopic history impact the severity of irritation and recovery from exposure and response to treatment for common hand skin products in both chronic irritant hand dermatitis and normal skin.

Topics: Adult; Dermatitis, Atopic; Dermatitis, Irritant; Dermatitis, Occupational; Epidermis; Erythema; Female; Hand Disinfection; Health Personnel; Humans; Male; Middle Aged; Occupational Exposure; Polymorphism, Genetic; Severity of Illness Index; Sodium Dodecyl Sulfate; Tumor Necrosis Factor-alpha; Young Adult

Occlusion of the skin is a risk factor for development of irritant contact dermatitis. Occlusion may, however, have a positive effect on skin healing. No consensus on the effect of occlusion has been reached.. To investigate skin barrier response to occlusion on intact and damaged skin.. In study A, the response to occlusion (nitrile glove material) for either 8 hr daily for 7 days or for 72 consecutive hours, respectively, was determined and compared with that of non-occluded skin. In study B, the response to occlusion of for 72 consecutive hours of skin that had been damaged by either sodium lauryl sulfate (SLS) or tape stripping, respectively, was determined and compared with that of to non-occluded pre-damaged skin. Skin barrier function was assessed by measurements of trans-epidermal water loss (TEWL) and erythema. In study A, stratum corneum lipids were analysed.. Occlusion of healthy skin did not significantly influence skin barrier function, ceramide profile or the ceramide/cholesterol ratio. Occlusion of the skin after SLS irritation resulted in higher TEWL than in the control (P = 0.049). Occlusion of the skin after tape stripping resulted in lower TEWL than in control skin (P = 0.007).. A week of occlusion did not significantly affect healthy skin, but was found to decrease healing of SLS-damaged skin, and to improve healing of tape-stripped skin.

Topics: Adult; Ceramides; Cholesterol; Dermatitis, Irritant; Epidermis; Erythema; Female; Humans; Male; Middle Aged; Nitriles; Skin; Sodium Dodecyl Sulfate; Surgical Tape; Water Loss, Insensible; Wound Healing; Young Adult

Determination of drug penetration in diseased skin represents a challenge.. To compare dermal microdialysis and tape-strip sampling of drug penetration in normal skin and skin with irritant dermatitis.. The two methodologies were employed simultaneously in 16 healthy volunteers. Samples were collected in a study of the penetration of a metronidazole cream formulation (Flagyl 1%) applied to forearm skin in both areas with irritant dermatitis and normal skin. Barrier perturbation and the depth of microdialysis probes were quantified by non-invasive bioengineering methods.. Microdialysis showed a significant threefold increase in metronidazole penetration in skin with irritant dermatitis compared with unmodified skin. Conversely, the concentration of metronidazole in tape-strip samples was significantly decreased in irritant dermatitis.. The selection of sampling methodology should be based on the skin layer of interest as well as the integrity of the skin barrier. Whenever the dermal tissue is the target for topical treatment, microdialysis sampling should be the method of choice.

Topics: Administration, Cutaneous; Adult; Analysis of Variance; Area Under Curve; Biological Availability; Dermatitis, Irritant; Dermatologic Agents; Erythema; Female; Humans; Linear Models; Male; Metronidazole; Microdialysis; Middle Aged; Skin; Skin Absorption; Sodium Dodecyl Sulfate; Ultrasonography; Water Loss, Insensible

This study involves development of amphiphilic gels consisting solely of nonionic surfactants bearing cyclosporine and characterized for microstructure, gelation temperature, and in vitro drug release into dermis. The formulation is nonirritant and suitable for topical application. Gels consisting of cyclosporine were prepared using different methods by mixing the solid gelator (sorbitan or glyceryl fatty acid esters) and the liquid phase (liquid sorbitan esters or polysorbates) and heating them at 60 degrees C to form a clear isotropic sol phase, and cooling this sol phase to form an opaque semisolid at room temperature. Gel microstructure was examined by phase contrast microscopy while gelation temperatures were measured by melting point apparatus and differential scanning calorimetry. These amphiphilic gels were evaluated in vitro for topical as well as transdermal delivery using rat skin mounted in a Franz diffusion cell. Gel microstructures consisted mainly of clusters of tubules of gelator molecules that had aggregated upon cooling of the sol phase, forming a 3D network throughout the continuous phase. The gels demonstrated thermoreversibility with robust gel network. At temperatures near the skin surface temperature, the gels softened considerably and moreover, it facilitated the drug to accumulate in dermis, thus making an ideal delivery vehicle of cyclosporine topically that can be used in treatment of psoriasis. Thus amphiphilic gels were demonstrated as the ideal vehicle for topical use of cyclosporine.

Topics: Administration, Topical; Animals; Calorimetry, Differential Scanning; Chemical Phenomena; Chemistry, Pharmaceutical; Chemistry, Physical; Cyclosporine; Drug Carriers; Drug Delivery Systems; Drug Stability; Erythema; Gels; Hexoses; Immunosuppressive Agents; In Vitro Techniques; Irritants; Polysorbates; Rats; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents

We investigated the biological response of regular human skin to alcohol-based disinfectants and detergents in a repetitive test design. Using non-invasive diagnostic tools such as transepidermal water loss, laser-Doppler flowmetry and corneometry, we quantified the irritative effects of a propanol-based hand disinfectant (Sterillium), its propanol mixture (2-propanol 45% w/w and 1-propanol 30% w/w), sodium lauryl sulfate (SLS) 0.5% and distilled water. The substances were applied in a 2-D patch test in a repetitive occlusive test design to the back. Additionally, we performed a wash test on the forearms that was supposed to mimic the skin affection in the normal daily routine of health care workers. In this controlled half-side test design, we included the single application of the hand rub, SLS 0.5% and water as well as a tandem application of the same substances. Patch test and wash test showed similar results. The alcohol-based test preparations showed minimal irritation rather comparable to the application of water. However, the detergent SLS produced stronger barrier disruption, erythema and dryness than the alcohol-based preparations. There was no additional irritation at the combined use of SLS and disinfectants. By contrary, there was even a decrease in barrier disruption and erythema induced by the tandem application of SLS followed by alcohol-based disinfection compared with the use of SLS alone. These findings show a less irritant effect of alcohol-based disinfectants on the skin than detergents. Our study shows that there is no summation of irritating effects of a common detergent and propanol and that the combination of washing and disinfection has a rather protective aspect compared with washing alone.

Topics: Adolescent; Adult; Dermatitis, Irritant; Dermatitis, Occupational; Detergents; Disinfectants; Erythema; Female; Hand Dermatoses; Hand Disinfection; Health Personnel; Humans; Laser-Doppler Flowmetry; Male; Middle Aged; Patch Tests; Quaternary Ammonium Compounds; Regional Blood Flow; Skin; Sodium Dodecyl Sulfate; Water; Water Loss, Insensible

In vivo levels of cytokines and presence of neutrophils and eosinophils in skin irritation are not well known. Our objective was to get more insight in inflammatory mediators and markers involved in single and repeated skin irritation. We sampled epidermis-derived fluid using a novel technology that includes application of a negative pressure on the skin after creation of micropores in the stratum corneum by a laser. In nine volunteers, transdermal fluid was sampled after a single 4-h 10% sodium lauryl sulphate exposure and a repeated 3-week exposure (0.1% sodium lauryl sulphate). Twenty-seven cytokines were assessed by multiplex assay, and IL-1alpha, eosinophil cationic protein and myeloperoxidase by enzyme-linked immunosorbent assay. Levels of eosinophil cationic protein were increased after irritation and correlated with levels of myeloperoxidase. The levels of inflammatory mediators showed large interindividual differences in unexposed and exposed skin. Despite this variation, several mediators clearly showed increased levels: CC chemokine ligand (CCL)11, CXCL10 and vascular endothelial growth factor after both single and repeated exposure, IL-1alpha and basic fibroblast growth factor after single exposure and interleukin-1 receptor antagonist (IL-1RA) after repeated exposure. After repeated exposure, CCL5 and the ratio IL-1RA/IL-1alpha both increased compared with single exposure. We conclude that single and repeated irritation induces differential and concerted expression of various inflammatory mediators and markers.

Topics: Adult; Biomarkers; Body Fluids; Cytokines; Dermatitis, Irritant; Eosinophil Cationic Protein; Erythema; Female; Humans; Inflammation Mediators; Male; Middle Aged; Peroxidase; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents

Skin irritability after a brief exposure to the model skin irritant, sodium lauryl sulphate (SLS), is known to vary considerably between individuals. A difference in the skin barrier to SLS may contribute to this variation. To date, no human in vivo data have been available on SLS penetration into the skin.. We studied whether the SLS penetration rate into the stratum corneum (SC) is related to impairment of the water barrier function and inflammation of the skin.. The penetration of SLS into the SC was assessed using a noninvasive tape-stripping procedure in 20 volunteers after a 4-h exposure to 1% SLS. Additionally, the effect of a 24-h exposure to 1% SLS on the skin water barrier function was assessed by measuring the transepidermal water loss (TEWL). The accompanying inflammation was quantified by measuring erythema.. The mean +/- SD diffusivity of SLS (D) and the SLS permeability coefficient (Kp) were 1.4 +/- 0.6 x 10(-8) cm2 h(-1) and 1.5 +/- 0.7 x 10(-3) cm h(-1), respectively. A multiple regression analysis showed that the baseline TEWL, SC thickness and SLS penetration parameters K (SC/water partition coefficient) and D clearly influenced the increase in TEWL after the 24-h irritation test (explained variance: r2 = 0.80). Change in erythema was mainly influenced by SC thickness.. We found that variation in the barrier impairment and inflammation of human skin depends on the SLS penetration rate, which was mainly determined by SC thickness.

Topics: Adolescent; Adult; Dermatitis, Contact; Disease Susceptibility; Erythema; Female; Humans; Male; Severity of Illness Index; Skin; Skin Absorption; Skin Tests; Sodium Dodecyl Sulfate; Water Loss, Insensible

Little is known about cytokines involved in chronic irritant contact dermatitis. Individual cytokine profiles might explain at least part of the differences in the individual response to irritation. Our objective was to investigate the relation between baseline stratum corneum (SC) cytokine levels and the skin response to a single and a repeated irritation test. This study also aimed to determine changes in SC cytokine levels after repeated irritation. Transepidermal water loss (TEWL) and erythema were measured in 20 volunteers after single 24-hr exposure to 1% sodium lauryl sulfate (SLS), and during and after repeated exposure to 0.1% SLS over a 3-week period. SC cytokine levels were measured from an unexposed skin site and from the repeatedly exposed site. Interleukin (IL)-1alpha decreased by 30% after repeated exposure, while IL-1RA increased 10-fold and IL-8 increased fourfold. Baseline IL-1RA and IL-8 values were predictors of TEWL and erythema after single exposure (r = 0.55-0.61). 6 subjects showed barrier recovery during repeated exposure. Baseline IL-1RA and IL-8 levels are likely to be indicators of higher skin irritability after single exposure to SLS. Barrier repair in some of the subjects might explain the lack of agreement between the TEWL response after single and repeated irritation.

Topics: Adult; Body Water; Cytokines; Dermatitis, Irritant; Epidermis; Erythema; Female; Humans; Hypersensitivity, Immediate; Interleukin 1 Receptor Antagonist Protein; Interleukin-1; Interleukin-8; Irritants; Male; Sialoglycoproteins; Sodium Dodecyl Sulfate

Easily applicable water-specific instruments measuring local oedema in skin are not available. The aim of this study is to demonstrate quantitative assessment of skin oedema with the dielectric technique by measuring increase of skin water content related to sodium lauryl sulphate (SLS)-induced irritant contact dermatitis.. Irritant skin reaction and resulting oedema were induced by an irritant patch test on volar forearms in 12 healthy volunteers with the application of 1% SLS for 6 h. After occlusion the volunteers were divided into two groups: the patch test site of group I (six volunteers) received no treatment other than a base cream for the skin reaction, while for group II (six volunteers) a strong corticosteroid (clobetasol propionate) was applied on the irritant skin. During a follow-up of 72 h, erythema was scored visually, and irritant-induced oedema was measured with a novel water-specific instrument MoistureMeter-D.. In the untreated irritant skin, a maximum increase of 45% in skin water content was found at 10 h postocclusion and water content was still elevated at 72 h. With these persons, the degree of oedema agreed well with the ultrasound-measured skin thickness (P=0.053). In the corticosteroid-treated skin, an increase of 8% in water content was measured during 72 h but there was no correlation between oedema and skin thickness. There was no correlation between erythema and oedema in untreated or corticosteroid-treated skin.. The new instrument can easily be applied for noninvasive quantitative evaluation of local oedema and fluid retention in irritant-exposed skin.

Topics: Adult; Anti-Inflammatory Agents; Body Water; Clobetasol; Dermatitis, Irritant; Edema; Electrochemistry; Erythema; Humans; Skin; Skin Diseases; Sodium Dodecyl Sulfate; Surface-Active Agents; Ultrasonography

There is evidence that a higher skin susceptibility may induce nonspecific erythematous or weak positive reactions to contact allergens in patch testing.. To evaluate whether simultaneous application of sodium lauryl sulphate (SLS) along with diagnostic patch tests with contact allergens can provide information regarding skin irritability which may help to discriminate allergic from nonspecific irritant reactions to contact allergens.. Between July 2001 and June 2003, this prospective study collected patch test data of 5971 patients from 19 centres in Germany and Austria in the Information Network of Departments of Dermatology (IVDK). In addition to contact allergens (standard series and eight known 'problematic' allergens with a low reaction index and a high positivity ratio: 1,3-diphenylguanidine, amerchol L-101, benzalkonium chloride, benzoyl peroxide, cocamidopropyl betaine, octyl gallate, phenyl mercuric acetate and propylene glycol), patches with SLS 0.5% and 0.25% aq. were applied. Reactions to the allergens and to SLS were analysed at the IVDK data centre. The association between an erythematous or positive reaction to a certain allergen and an irritant reaction to SLS was assessed with logistic regression analysis, at the same time controlling for the influence of age and sex.. Of the 29 allergens of the standard series, 23 and 21 gave a higher percentage of nonspecific erythematous reactions in patients with an irritant reaction to 0.25% and 0.5% SLS, respectively, in comparison with SLS-negative patients. All eight 'problematic' allergens gave an increased percentage of nonspecific erythematous reactions. Similarly, 22 and 21 allergens of the standard series gave a higher percentage of positive allergic reactions in patients with an irritant reaction to 0.25% and 0.5% SLS, respectively, and seven of the eight 'problematic' allergens gave a higher percentage of positive allergic reactions (exception: octyl gallate). For most allergens, the markers of skin reaction (reaction index and positivity ratio) were worse in SLS-positive patients. Differences were more pronounced when testing with SLS 0.25% than with SLS 0.5%.. Because there is a convincing association between skin irritability (evaluated by SLS test) and the degree of skin reaction to contact allergens, the SLS test may help in deciding whether a doubtful erythematous or weakly 'positive' skin reaction should be interpreted as allergic or irritant.

Topics: Adult; Allergens; Dermatitis, Allergic Contact; Dermatitis, Atopic; Dermatitis, Contact; Dermatitis, Occupational; Diagnosis, Differential; Diagnostic Errors; Erythema; Female; Humans; Male; Patch Tests; Predictive Value of Tests; Prospective Studies; Sodium Dodecyl Sulfate

The interaction between potential irritants in the workplace might be important because workers are not usually exposed to a single irritant, but to multiple potentially harmful substances. Physical irritant contact dermatitis caused by friction or mechanical abrasion is a common occupational dermatosis. Prolonged water exposure by occlusion is also common in the workplace. Several studies have revealed the negative effect of the common anionic detergent sodium lauryl sulphate (SLS) on permeability barrier function.. To study the additive impairment of permeability barrier function by mechanical irritation combined with 0.5% SLS or prolonged water exposure by occlusion, as models of mild irritation.. The volar forearms of 20 healthy volunteers were exposed to mechanical irritation and occlusion with water or 0.5% SLS for four consecutive days in a combined tandem repeated irritation test (TRIT). Permeability barrier function was measured with a Tewameter TM 210. Irritation was assessed with a Chromameter CR 300 and a visual score.. Barrier disruption in our model was rated as follows: occlusion with SLS and mechanical irritation > occlusion with SLS > occlusion with water and mechanical irritation > mechanical irritation and occlusion with water > occlusion with a glove and mechanical irritation > mechanical irritation > occlusion with water. Barrier disruption caused by occlusion or mechanical irritation was enhanced by the tandem application. The choice of irritant under occlusion, time of occlusion and order of tandem application all affected the degree of barrier disruption. Evaporimetry was able to detect early stages in the development of an irritant reaction before it became visible. Chromametry was not able to detect this early response.. Physical irritants (friction, abrasive grains, occlusion) and detergents such as SLS represent a significant irritation risk and should be minimized, especially when acting together, as shown in our TRIT model.

Topics: Adult; Dermatitis, Irritant; Dermatitis, Occupational; Electric Capacitance; Epidermis; Erythema; Female; Humans; Irritants; Male; Physical Stimulation; Severity of Illness Index; Sodium Dodecyl Sulfate; Stress, Mechanical; Water Loss, Insensible

Irritant patch testing is often performed as a 24- or 48-h occlusive patch test with low concentrations of sodium lauryl sulphate (SLS).. The aim of this study was to investigate potential ways to shorten this test procedure and obtain precise test results.. Thirty-six healthy volunteers underwent irritant patch testing with different pretreatments (PT) of the test fields. Occlusive test chambers were applied on the upper back with SLS 0.5%, 1%, 2% and 5% in large Finn Chambers(R). The patches were removed after 4 and 24 h, respectively, depending on the concentration used. Test fields were pretreated as follows: PT 0, field without any PT (control); PT 1, prick with lancet; PT 2, prick with test stamp; PT 3, scratch with lancet; PT 4, incision with standardized incision instrument (0.1-0.2 mm depth). Skin reactions were evaluated by transepidermal water loss (TEWL), skin erythema and skin hydration and as well by a visual score (VS) at 4, 24 and 72 h.. Our data show an obvious distinction between PT 0-2 and PT 3-4 at all measurement methods. The average TEWL values with PT 3-4 were higher than those with PT 0-2, especially on the 4-h course. This distinction may derive from the shape and size of the skin impairment achieved by PT 3-4, leading to a mechanical barrier disruption. However, SLS may infiltrate directly into deeper skin layers supported by capillarity. Consequently, no or little penetration through the epidermis and interaction with its structures occurs, which is responsible for irritant skin reactions. The SLS dose in the upper skin layers is therefore lower at these PTs. The lower remaining dose of SLS also explains this distinction, especially for the VS. Additionally, there are presumed reactions in deeper layers of the epidermis and dermis at PT 3-4.. In summary, all data suggest a different reaction pattern from the classical irritant response. Therefore, application without any PT seems to be best suited for irritancy skin testing, especially for visual assessment. PTs prior to irritant patch testing have been shown to be unjustifiable.

Topics: Adult; Body Water; Dermatitis, Irritant; Drug Delivery Systems; Erythema; Female; Humans; Irritants; Male; Middle Aged; Patch Tests; Reproducibility of Results; Skin Irritancy Tests; Sodium Dodecyl Sulfate; Time Factors; Water Loss, Insensible

Little is known of the predictive value of methods to test an individual's susceptibility to acquiring occupational contact dermatitis. Recently, the recovery rate after induced irritation was suggested for this purpose. Although it is likely that repeated exposure to sodium lauryl sulphate (SLS) is preferable to a single application, there is little evidence to support this idea. Similarly, little is known about whether the outcome of a repeated SLS test can be predicted by a brief test.. We studied the relationship between the skin reaction after a repeated SLS test and two brief tests, devoting special attention to the recovery rate.. In 29 healthy volunteers, we measured transepidermal water loss (TEWL) and erythema after applying 0.03, 0.1 and 0.3% SLS for 6 h, 3 days per week, over a course of 3 weeks. The data were compared with the effects after applying 0.1, 0.3 and 1.0% SLS for 24 h and with 10 and 15 repetitions of tape stripping.. A poor correlation was found between the repeated test and the brief SLS test, or tape stripping, when using an increase in TEWL (r = 0.04 and 0.26, respectively) or its recovery rate (r = - 0.01 and 0.42, respectively).. We presume that in a repeated test of sufficient duration, additional mechanisms come into play that are absent in a brief test, e.g. an alteration in the thickness of the epidermis, with a resulting change in the permeability of SLS. When such an effect differs between subjects it could explain the lack of agreement between the acute and the repeated tests. At present, a brief irritation test will, in all likelihood, be unable to assess an individual's susceptibility to occupational contact dermatitis.

Topics: Adult; Dermatitis, Allergic Contact; Dermatitis, Occupational; Erythema; Female; Humans; Hypersensitivity, Immediate; Male; Patch Tests; Permeability; Skin; Sodium Dodecyl Sulfate; Water Loss, Insensible

Non-invasive bioengineering methods are widely used in the assessment of irritant skin reactions.. To assess the ability of eight non-invasive measurement techniques to distinguish changes in skin conditions over time, these changes being induced by five different irritants.. The following techniques were compared in a multivariate analysis: laser-Doppler perfusion imaging (LDI), laser-Doppler flowmetry (LDF), transepidermal water loss (TEWL), visual scoring (VS), colorimetric measurements (Chromameter CR 200 a* and L* scales), Mexameter Hb scale (Mexa Hb) and capacitance (Corneometer CM 820). Irritants tested were sodium lauryl sulphate 2% (SLS), tape stripping (TS), tretinoin 0.05% (TRET), ultraviolet (UV) exposure to 30 W m(-2) UVB/95 W m(-2) UVA, and dithranol 0.5% (DIT). Measurements were performed at baseline and after 24, 48 and 72 h. The study was conducted on the upper back of 11 healthy volunteers of both sexes aged 27-51 years.. For DIT it was possible to discriminate over time with CR 200 a* and L*, VS, LDI, LDF and Mexa Hb. In SLS discrimination over time was seen with TEWL and LDF. Discrimination in TS was demonstrated for TEWL, VS, CR 200 a*, CM 820, LDF, LDI and Mexa Hb. In TRET discrimination ability was seen for LDI, LDF, Mexa Hb and VS. For UV it was possible to discriminate using VS, TEWL, LDF, LDI and Mexa Hb.. Different irritation patterns need different measurement modalities in order to give optimal discrimination over time.

Topics: Adult; Analysis of Variance; Anthralin; Calorimetry; Dermatitis, Irritant; Erythema; Female; Humans; Irritants; Laser-Doppler Flowmetry; Male; Middle Aged; Multivariate Analysis; Severity of Illness Index; Skin; Sodium Dodecyl Sulfate; Tretinoin; Ultraviolet Rays; Water Loss, Insensible

Quercetin is a bioflavonoid with antioxidant and anti-inflammatory activity. The purpose of this study was to examine the effect of quercetin on acute skin irritation, with special interest in the skin barrier function recovery. Acute irritant contact dermatitis was induced in 15 patients by 24-h occlusion of 2% sodium lauryl sulfate (SLS) (day (D) 1). The influence of application on SLS-irritated skin of topical quercetin for 5 consecutive Ds, compared to vehicle and controls, was studied. Parameters measured were transepidermal water loss (TEWL) and erythema index. Final measurements were taken on D 7 after a 1-D rest period. TEWL and the erythema index continued to rise 2 D after application of SLS and 1 D after treatment with quercetin, vehicle or controls. Both TEWL and erythema values at D 7 did not return to values before the SLS barrier disruption at all the test sites. Therefore, quercetin topically applied after induction of irritant contact dermatitis does not appear to increase the recovery of barrier function and erythema caused by SLS.

Topics: Administration, Cutaneous; Adult; Analysis of Variance; Anti-Inflammatory Agents; Antioxidants; Area Under Curve; Dermatitis, Irritant; Erythema; Female; Follow-Up Studies; Humans; Irritants; Male; Pharmaceutical Vehicles; Placebos; Quercetin; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents; Water Loss, Insensible

Chronic irritant contact dermatitis (ICD) is a common skin disease, especially in the workplace, but determining the recovery time of chronic ICD is not easy. To measure the recovery time of chronic ICD, we examined the skin reactivity to a model surfactant, sodium lauryl sulfate (SLS), on previous chronic ICD and normal sites by visual grade and non-invasive instruments. Chronic ICD was induced on the forearms of 10 volunteers (aged 23 to 43 years) by occluded application of 1% SLS for 30 min on 5 consecutive days each week for 3 weeks. Previous ICD and normal sites were provoked by the occluded application of 7.5% SLS for 30 min daily on 4 consecutive days, 2, 5 and 10 weeks after induction. Skin reactivity was assessed daily by awarding visual erythema scores, visual scale scores and measuring transepidermal water loss, skin color reflectance, and electrical capacitance. Skin reactivity of previous chronic ICD sites to SLS showed hyperreactivity compared to normal sites even after the 10th week post-induction.

Topics: Adult; Arm; Chronic Disease; Colorimetry; Dermatitis, Allergic Contact; Electric Conductivity; Erythema; Female; Humans; Irritants; Male; Severity of Illness Index; Skin Pigmentation; Sodium Dodecyl Sulfate; Time Factors; Water Loss, Insensible

The penetration of topically applied drugs is altered in diseased or barrier-damaged skin. We used microdialysis in the dermis to measure salicylic acid (SA) penetration in hairless rats following application to normal (unmodified) skin (n = 11) or skin with perturbed barrier function from (1) tape-stripping (n = 5), (2) sodium lauryl sulphate (SLS) 2% for 24 h (n = 3) or (3) delipidization by acetone (n = 4). Prior to the experiment, transepidermal water loss (TEWL) and erythema were measured. Two microdialysis probes were inserted into the dermis on the side of the trunk and 5% SA in ethanol was applied in a chamber overlying the probes. Microdialysis sampling was continued for 4 h, followed by measurements of probe depth by ultrasound scanning. SA was detectable in all samples and rapidly increasing up to 130 min. Microdialysates collected between 80 and 200 min showed mean SA concentrations of 3 microg/ml in unmodified and acetone-treated skin, whereas mean SA concentrations were 280 microg/ml in SLS-pretreated skin and 530 microg/ml in tape-stripped skin (P < 0.001). The penetration of SA correlated with barrier perturbation measured by TEWL (P < 0.001) and erythema (P < 0.001). A correlation between dermal probe depth and SA concentration was found in unmodified skin (P = 0.04). Microdialysis sampling in anatomical regions remote from the dosed site excluded the possibility that SA levels measured were due to systemic absorption. Microdialysis sampling of cutaneous penetration was highly reproducible. Impaired barrier function, caused by irritant dermatitis or tape stripping, resulted in an 80- to 170-fold increase in the drug level in the dermis. This dramatic increase in drug penetration could be relevant to humans, in particular to topical treatment of skin diseases and to occupational toxicology.

Topics: Absorption; Acetone; Animals; Biological Transport; Erythema; Female; Microdialysis; Physical Stimulation; Rats; Rats, Sprague-Dawley; Reference Values; Salicylic Acid; Skin; Skin Diseases; Sodium Dodecyl Sulfate; Solvents; Surface-Active Agents; Ultrasonography; Water Loss, Insensible

Patch testing is an invaluable tool for the experimental induction of acute irritant contact dermatitis (ICD), with a variety of chamber systems available for use. Ideally, the inflammatory reactions produced should be of uniform intensity across the test area, thereby facilitating grading of the response and tissue sampling for histopathological studies. Unfortunately, annular, follicular and/or blotchy erythema frequently occur. In this study, we set out to compare the performance of 5 patch test systems (8 mm, 12 mm and 18 mm Finn Chambers; 19 mm and 25 mm Hilltop chambers) when testing normal healthy volunteers with sodium lauryl sulfate at concentrations selected to produce mild, moderate and moderately severe reactions. Visual assessment of the patch test sites revealed good dose responses with all 5 chamber types. Uniformity of erythema across the test site was more closely linked to the actual intensity of response than the delivery system itself, mild reactions being far less likely to display homogeneous erythema than moderately severe reactions. Extra large chambers did not perform significantly better than smaller chambers. Balancing the need for a uniform reaction pattern and adequate tissue sampling area, against the exposure risk, we conclude that 12 mm Finn Chambers represent the optimum patch test system for acute SLS-induced irritation where histopathological investigations are the ultimate aim.

Topics: Adult; Dermatitis, Irritant; Erythema; Female; Humans; Middle Aged; Patch Tests; Skin; Sodium Dodecyl Sulfate

An undesirable side-effect of retinoid treatment is skin fragility. As desmosomes are important in maintaining the cohesion of epidermal keratinocytes, we investigated whether all-trans-retinoic acid (RA) compromises desmosome expression in human epidermis, thereby predisposing skin to fragility. Solutions containing 0.025% RA, 5% sodium dodecyl sulphate (SDS) as an irritant control, or vehicle alone were applied to three sites on the buttocks of normal volunteers (n = 9). Treated sites were occluded for 4 days, and biopsies taken under local anaesthesia. Cryostat sections were stained with a panel of antibodies to desmosomal proteins and visualized by immunofluorescence microscopy. Stained sections were randomized and assessed for intensity of staining. The epidermal thickness of each treated site was quantified by image analysis. Western blots of epidermal desmocollins were quantified by densitometry. RA and SDS treatments significantly, but equivalently, increased epidermal thickness compared with vehicle. Immunohistochemically, both RA and SDS were shown to reduce epidermal staining for desmoplakin, desmoglein 1, plakophilin 1 and desmocollin 3 equally compared with vehicle-treated skin (P < 0.001). RA produced a greater reduction in desmocollin 1 staining compared with SDS (P < 0.001). Similar reductions in desmocollins were found by Western blot analysis. Reduced desmocollin expression may indicate compromised desmosomal adhesion, leading to the skin fragility that results from retinoid treatment.

Topics: Adult; Blotting, Western; Desmosomes; Erythema; Female; Humans; Immunohistochemistry; Irritants; Keratolytic Agents; Male; Middle Aged; Skin Diseases; Sodium Dodecyl Sulfate; Surface-Active Agents; Tretinoin

Cigarette smoking significantly alters the inflammatory response in the skin following application of irritants and rubefacients. The mechanism of this effect is unknown. There are thousands of components in cigarette smoke that may be pharmacologically important, but there is evidence to suggest that nicotine may play an important role in the observed effect on the inflammatory process.. This was an interventional study to assess cutaneous responsiveness to different stimuli after transdermal nicotine administration in volunteer subjects. Cutaneous testing was performed at baseline and at weeks 2 and 4 (the end) of the study.. The department of Dermatology, University Hospital of Wales, Cardiff.. Ten lifelong nonsmokers were recruited for the study.. Nicotine patches were applied daily for 1 month.. The following tests were performed: application of 2 times the minimal irritancy dose of sodium lauryl sulfate, irradiation with 2 times the minimal erythema dose of UV-B, measurement of cutaneous vasodilation following application of ethyl and hexyl nicotinate, and reactive hyperemia following arterial occlusion.. There was a significant reduction in the cutaneous inflammatory response to sodium lauryl sulfate (P < .001) and irradiation with UV-B (P < .003) and a reduction in reactive hyperemia (P < .03) after 2 weeks of treatment, which returned values to normal at 4 weeks. There was no change in blood flow following application of topical nicotinates.. Nicotine administration via a transdermal delivery system suppresses the cutaneous inflammatory response to sodium lauryl sulfate and UV-B, as well as triggers a transient suppression of reactive hyperemia following arterial occlusion. The apparent anti-inflammatory effects of smoking cigarettes can therefore only partially be explained as a long-term effect of nicotine.

Topics: Administration, Cutaneous; Adult; Arterial Occlusive Diseases; Brachial Artery; Central Nervous System Stimulants; Dermatitis; Dermatitis, Contact; Dermatitis, Irritant; Erythema; Female; Follow-Up Studies; Humans; Hyperemia; Irritants; Male; Nicotine; Nicotinic Acids; Polymethacrylic Acids; Polyvinyls; Radiation Dosage; Regional Blood Flow; Skin; Smoking; Sodium Dodecyl Sulfate; Surface-Active Agents; Tobacco Use Cessation Devices; Ultraviolet Rays; Vasodilation

Our understanding of the details of the recovery time of acute irritant contact dermatitis (ICD) is limited. We examined skin reactivity to a model surfactant, sodium lauryl sulfate (SLS), on previous acute ICD and normal sites over time with visual grading and noninvasive instruments. Acute ICD was induced on the upper arms of 18 volunteers (aged 30 to 51 years) by occluded application of 1% SLS for 24 h. Previous ICD and normal sites were provoked by occluded application of 2% or 7.5% SLS 30 min daily 4 consecutive days. Skin reactivity was assessed daily by visual erythema scoring (VES), transepidermal water loss (TEWL), skin color reflectance (SCR) and electrical capacitance (EC). Skin function of previous ICD sites assessed by VES, TEWL, SCR, and EC did not normalize until 2 weeks later; all parameters of previous ICD returned to normal after 3 weeks. While skin reactivity to 2% and 7.5% SLS showed no differences between previous ICD and normal sites at 4 weeks, differences of irritant reactivity especially 7.5% SLS between previous ICD and normal sites were significant at 3 weeks post-provocation. Our results demonstrate that irritation evaluated with irritant provocation was long-lasting, even though skin functional parameters assessed by various bioengineering instruments returned to normal. Complete recovery of skin function including irritability after acute ICD induced by 1% SLS was achieved approximately 4 weeks later. The date were generated with a model surfactant; it remains to be determined whether similar responses will be noted with chemicals of different physiochemical properties.

Topics: Acute Disease; Adult; Dermatitis, Contact; Dermatitis, Irritant; Electric Conductivity; Erythema; Female; Humans; Male; Middle Aged; Severity of Illness Index; Skin Pigmentation; Sodium Dodecyl Sulfate; Time Factors; Water Loss, Insensible

Sodium lauryl sulfate (SLS), a surfactant frequently used in the induction of experimental irritant contact dermatitis in animals and in humans, characteristically induces a dose-related increase in TEWL (transepidermal water loss). Ceramides are considered to be important in the regulation of the skin barrier. We therefore examined the relationship between initial ceramide content of stratum corneum and induced changes in skin color (erythema) and barrier function, after SLS application under occlusion (1% and 3% in water) to the forearm of 14 volunteers. Stratum corneum sheets were removed, stratum corneum lipids extracted, and ceramide composition determined from chromatograms (TLC) using densitometry. After determining baseline skin color and TEWL at each area, 2 samples of stratum corneum were obtained from each volunteer. Clinical and instrumental controls of the SLS-induced irritation were performed at 24, 48, 72 and 96 h. Erythema was evaluated by colorimetry: barrier impairment by changes in TEWL. We found inverse correlations between baseline ceramide 61 (weight) and the 24 h erythema score for SLS 3%, between ceramide 1 and 24 h TEWL, and between ceramide 611 and 72 h TEWL for SLS 3%. Our findings suggest that low levels of these ceramides may determine a proclivity to SLS-induced irritant contact dermatitis.

Topics: Adult; Analysis of Variance; Biological Assay; Case-Control Studies; Ceramides; Colorimetry; Dermatitis, Irritant; Disease Susceptibility; Epidermis; Erythema; Female; Humans; Linear Models; Skin Absorption; Sodium Dodecyl Sulfate; Surface-Active Agents; Water Loss, Insensible

Although the induction of acute irritant dermatitis by detergents has been studied extensively in recent years, our understanding of the cell biological events in the repair phase, and its relevance for the development of chronic irritant dermatitis is limited. Here we studied the reaction pattern of human skin to short-term application of sodium dodecyl sulphate (SDS) in a model that induced a minimal acute inflammatory reaction (absence of polymorphonuclear leucocytes, PMN) and did not have cytopathic effects on the epidermal keratinocytes as determined by histological investigation. All parameters were measured up to 14 days after exposure to SDS. Application of SDS caused disturbances of barrier function as measured by transepidermal water loss and had vascular effects as judged by erythema. Several cell biological markers for epidermal growth and differentiation were examined by immunohistochemistry. A rapid and strong induction of the cornified envelope precursor protein involucrin was seen in the stratum spinosum, with a peak at 24 h. Within 24 h a strong upregulation of epidermal fatty acid binding protein (E-FABP) was noted, with a peak at 7 days after injury. Cellular proliferation in the basal layer was increased fivefold as assessed by nuclear staining for the Ki-67 antigen, showing a peak at 48 h. Surprisingly, no significant induction of cytokeratin 16 and SKALP/elafin expression, two markers associated with epidermal hyper-proliferation and inflammation, was seen. These findings suggest that the cellular changes following exposure to detergent are distinct from those seen in other forms of skin injury. We would speculate that the epidermal response to detergent exposure is primarily directed at restoration of barrier function.

Topics: Adult; Biomarkers; Carrier Proteins; Cell Differentiation; Cell Division; Dermatitis, Irritant; Detergents; Epidermis; Erythema; Fatty Acid-Binding Protein 7; Fatty Acid-Binding Proteins; Female; Humans; Keratinocytes; Keratins; Ki-67 Antigen; Male; Models, Biological; Myelin P2 Protein; Neoplasm Proteins; Protein Precursors; Proteinase Inhibitory Proteins, Secretory; Proteins; Sodium Dodecyl Sulfate; Time Factors; Tumor Suppressor Proteins

Topics: Anthralin; Biophysical Phenomena; Biophysics; Body Water; Dermatitis, Irritant; Erythema; Humans; Skin; Skin Physiological Phenomena; Sodium Dodecyl Sulfate

Topics: Adolescent; Adult; Body Water; Dermatitis, Irritant; Electric Conductivity; Erythema; Humans; Irritants; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents

The intercellular lipids of stratum corneum are predominantly formed by cholesterol, ceramides and free fatty acids. Cholesterol synthesis is inhibited by statins, cholesterol-lowering drugs (lovastatin, pravastatin, simvastatin). The present study was undertaken to examine the effect of these drugs on skin barrier function. Knowledge about the effect on epidermis of systemic inhibition of cholesterol synthesis may improve our understanding of the skin barrier function. Seventeen statin-treated subjects were compared to controls. All were patch-tested with sodium lauryl sulphate (SLS), and the skin was evaluated after 24 h and after 7 days by measurement of transepidermal water loss (TEWL), erythema and visual scoring. After 24 h as well as after one week erythema was significantly less pronounced in the statin-treated group than in controls (p < 0.001). No significant differences in TEWL were found between the groups at any time. The results imply a decreased bioavailability of SLS in the statin-treated group, while no evidence for an altered permeability barrier to water was found.

Topics: Adult; Aged; Anticholesteremic Agents; Biological Availability; Cholesterol; Erythema; Female; Galvanic Skin Response; Humans; Hypercholesterolemia; Irritants; Lovastatin; Male; Middle Aged; Patch Tests; Permeability; Pravastatin; Simvastatin; Skin; Sodium Dodecyl Sulfate; Water Loss, Insensible

Patients with X-linked recessive ichthyosis (RXLI) were studied as a model of the effect of disturbed epidermal lipid composition on skin barrier function. Thirteen patients with RXLI and 15 age- and sex-matched controls were patch-tested with sodium lauryl sulphate (SLS) 0.5% for 24 h. Basal skin properties and skin response to SLS were studied by measurement of transepidermal water loss (TEWL), electrical capacitance and erythema index. No statistically significant difference in basal TEWL was found between the two groups. The skin response to SLS was found to be statistically significantly increased in controls compared to ichthyosis patients, when evaluated by TEWL. When evaluated by erythema index a statistically significant increase in redness was found in controls, but not in ichthyosis patients. Electrical capacitance, reflecting skin hydration, was significantly reduced in RXLI patients as compared to controls. The water permeability barrier in RXLI patients was not found to be impaired, and skin reactivity was found to be decreased in RXLI patients as compared to controls.

Topics: Adult; Body Water; Case-Control Studies; Erythema; Female; Galvanic Skin Response; Genes, Recessive; Humans; Ichthyosis, X-Linked; Irritants; Lipid Metabolism; Male; Middle Aged; Patch Tests; Permeability; Skin; Sodium Dodecyl Sulfate; Water Loss, Insensible

To quantify the dose-response relation of irritant-induced erythema, we examined inflammation in human skin after application of an irritant, using perpendicular polarized photography and diffuse reflectance spectroscopy as compared to clinical visual scoring. The ventral forearms of 11 healthy subjects were patch-tested for 24 h under occlusion in finn chambers with five concentrations of the irritant sodium lauryl sulfate. The tested sites and three control sites were evaluated clinically for erythema at 24, 48, and 72 h after occlusion, photographed using standard and perpendicular polarized photography, and measured by diffuse reflectance spectroscopy. All photographs were evaluated for erythema by three investigators. Diffuse reflectance spectra were analyzed, and changes in apparent oxyhemoglobin and deoxyhemoglobin concentrations were estimated. Clinical and photographic assessments of erythema yielded similar linear dose-response relations. A linear dose-response relation, with no minimum threshold, also was obtained for changes in the apparent oxyhemoglobin concentration with increasing irritant dose, whereas the apparent deoxyhemoglobin concentrations were unchanged with increasing dose. These results show that diffuse reflectance spectroscopy permits the characterization of irritant-induced inflammation in terms of a single parameter, the apparent concentration of oxyhemoglobin, and that irritant-induced inflammation primarily involves the capillaries and the superficial arterial plexus.

Topics: Dose-Response Relationship, Drug; Erythema; Humans; Oxyhemoglobins; Photography; Skin; Sodium Dodecyl Sulfate; Spectrophotometry, Infrared; Time Factors

Topics: Animals; Body Water; Data Display; Dermatitis, Irritant; Edema; Erythema; Guinea Pigs; Laser-Doppler Flowmetry; Patch Tests; Regional Blood Flow; Severity of Illness Index; Skin; Sodium Dodecyl Sulfate; Tretinoin

Topics: Adult; Body Water; Dermatitis, Irritant; Epidermis; Erythema; Female; Forearm; Genetic Variation; Humans; Male; Patch Tests; Permeability; Sodium Dodecyl Sulfate

Topics: Acetylcysteine; Antioxidants; Dermatitis, Irritant; Dimethyl Sulfoxide; Edema; Erythema; Humans; Ointments; Sodium Dodecyl Sulfate; Tumor Necrosis Factor-alpha

Topics: Alopecia; Animals; Body Water; Dermatitis, Irritant; Disease Models, Animal; Drug Evaluation, Preclinical; Erythema; Female; Histamine Release; Industrial Oils; Intradermal Tests; Irritants; Male; Nicotinic Acids; Ointments; Patch Tests; Permeability; Sodium Dodecyl Sulfate; Sodium Hydroxide; Swine; Swine, Miniature; Toluene

It has recently been suggested that the lipid-soluble, antibacterial agent triclosan possesses an anti-inflammatory effect in the oral cavity. The aim of the present study was to examine whether triclosan can protect the skin from the irritation or inflammation that may be caused by exposure to sodium lauryl sulphate (SLS). Finn Chamber patch tests on the forearms of 10 volunteers showed that a mixture of SLS and triclosan caused no inflammation, whereas SLS alone caused reactions in all the subjects. Pre-treatment with triclosan before SLS exposure had a slight effect whereas treatment after exposure showed a significant effect. It is suspected that the reported anti-gingivitis effect of triclosan may at least in part be explained by an anti-inflammatory effect.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Dermatitis, Contact; Dermatitis, Irritant; Erythema; Female; Forearm; Gingivitis; Humans; Male; Middle Aged; Patch Tests; Pilot Projects; Polysorbates; Sodium Dodecyl Sulfate; Triclosan

Although surfactant-induced acute irritant dermatitis has been extensively studied, our understanding about the induction and repair of the clinically more relevant chronic form is limited.. Our purpose was to investigate qualitative and quantitative differences in surfactant-induced irritant skin reactions from cumulative exposure to structurally unrelated surfactants and to compare the maximal irritant responses from this model with corresponding reactions noted in a previously reported acute irritation model.. Sodium lauryl sulfate (SLS), dodecyl trimethyl ammonium bromide (DTAB), and potassium soap were the model irritants. Surfactant solutions (7.5%) were applied for 20 minutes daily (for 8 consecutive days excluding the weekend) to the volar aspect of the forearm of 11 volunteers. Irritant reactions were repeatedly assessed until complete healing was indicated by visual assessment and by measurements of transepidermal water loss (TEWL), erythema (skin color reflectance), and stratum corneum hydration (electrical capacitance). Maximum irritant responses were compared with corresponding reactions from an acute irritation model.. TEWL was increased by SLS and DTAB to the same extent, but erythema was significantly higher in DTAB-treated skin. Skin dryness, as demonstrated by decreased capacitance values and increased scores for scaling and fissuring, was significantly more pronounced than in an acute irritation model for SLS and DTAB, although no difference was detected between the two surfactants. Potassium soap led to a slight increase in TEWL, whereas the remaining features were not significantly changed.. This chronic irritation model appears to represent the clinical situation of irritant contact dermatitis with pronounced skin dryness more closely than the acute irritation model. The present study confirms that an extended time is needed for complete healing of irritant skin reactions. We also demonstrated that the evaluation of the irritation potential of diverse surfactants depended significantly on the feature evaluated (erythema vs electrical capacitance and TEWL), on the mode of application (acute vs cumulative), and, in the cumulative model, on the point of observation.

Topics: Adult; Dermatitis, Irritant; Double-Blind Method; Electric Conductivity; Erythema; Evaluation Studies as Topic; Humans; Irritants; Lipids; Middle Aged; Models, Biological; Quaternary Ammonium Compounds; Skin; Soaps; Sodium Dodecyl Sulfate; Surface-Active Agents; Time Factors; Water Loss, Insensible; Wound Healing

Despite the frequency of irritant contact dermatitis, very little is known about the duration of barrier function impairment following cumulative irritant contact dermatitis. We studied post-irritation irritant reactivity by assessing the response to SLS irritation in previously irritated sites. Cumulative irritant contact dermatitis was induced on the forearms of 15 volunteers aged 18 to 50 years by repeated occluded application of 0.5% SLS 1 h per day over 3 weeks. 3, 6 and 9 weeks later, previously irritated and unirritated control sites were challenged with 2% SLS under occlusion for 23 h. Irritation was assessed by visual scoring, transepidermal water loss (TEWL) as an indicator of epidermal barrier function, and capacitance as a parameter of epidermal water content. While no difference in irritant reactivity between pre-irritated and unirritated sites was observed 3 weeks following irritant contact dermatitis, there was a significant hyporeactivity of previously irritated skin as expressed by clinical scores, TEWL and capacitance at 6 and 9 weeks. Our results indicate that epidermal barrier function remains altered even 9 weeks after cumulative irritant contact dermatitis. With regard to patch testing, post-irritation hyporeactivity might be a cause of false-negative tests on previously irritated sites.

Topics: Adolescent; Adult; Body Water; Dermatitis, Irritant; Desiccation; Epidermis; Erythema; Female; Humans; Humidity; Hyperpigmentation; Irritants; Male; Middle Aged; Permeability; Skin; Sodium Dodecyl Sulfate; Time Factors

Nickel is a very common contact allergen, with some reports showing that more than 10% of women are affected. It is therefore important to be able to assess the risk of elicitation of nickel dermatitis in such individuals, particularly in relation to repeated exposure to low levels of this metal. It has been shown previously that under the conditions of a 48-h occluded patch test, some subjects will react to as little as 0.5 ppm nickel on compromised skin. In the present study, the effect of repeated open nickel application combined with repeated treatment with the anionic surfactant sodium dodecyl sulphate has been evaluated on the hand skin of 4 nickel-allergic subjects. Despite 2 of these being known to be particularly sensitive, there was no evidence of a nickel-allergic reaction following 2x daily immersion of hand skin sites in up to 1 ppm nickel over a period of 23 days.

Topics: Adult; Dermatitis, Allergic Contact; Erythema; Female; Hand; Humans; Immersion; Male; Nickel; Skin; Skin Diseases; Sodium Dodecyl Sulfate; Thumb

In an evaluation of the safety of new chemicals, of products containing them, or of novel formulations of existing chemicals which may come into contact with the skin, it is important to incorporate an assessment of specially susceptible sub-populations. Such a group is represented by those who are more likely to experience sensory effects such as stinging. Since these individuals are easily and rapidly identifiable, we investigated whether they represented a group who were also more susceptible to the effects of an irritant. The primary purpose was to discover whether 'stingers' might represent an easily and rapidly identifiable sub-population with a more generally increased tendency to give skin responses. The response to a 0.3% sodium dodecyl sulphate patch test was assessed in a group of 25 'stingers' and compared to the response in 25 'non-stingers'. There was no difference in either the pattern or strength of the irritant response assessed by subjective erythema and dryness scores. Thus the data suggest that there is no correlation between the susceptibility of an individual to a skin stinging response and an irritation reaction.

Topics: Erythema; Female; Humans; Irritants; Lactates; Lactic Acid; Male; Pain Threshold; Paresthesia; Patch Tests; Skin; Sodium Dodecyl Sulfate

The present trial was designed to evaluate clinical scores (single observer) of sodium lauryl sulphate (SLS)-induced skin irritation in a group of subjects (n = 10) over a 10-day period along with various skin function parameters. In order to avoid significant variations due to secondary phenomena, the following parameters were recorded with non-invasive instruments in this order: skin capacitance (C1; arbitrary units; CM420 Corneometer), transepidermal water loss (TEWL; g/m2.h; Evaporimeter) and laser Doppler flowmetry (CBFV: cutaneous blood flow values; Periflux). All examinations were performed during winter on reclined relaxed subjects present for at least 10 min in a test room with controlled temperature and relative humidity (t degrees: 19.5-20.7 degrees C and RH: 47.3-60.3%). The analysis of differential data (delta = value at tx-value before test; 2-way ANOVA) was made on single parameters as a function of site (volar forearm versus neck) and time (from 24 h after 48-h occlusion with 5% SLS up to 10 days later). The profile of erythema scores over time differed between neck and forearm, but the delta CBFV readings with the laser Doppler instrument did not detect significant site-time interactions. Roughness (blind evaluation with palpating finger) and capacitance readings (delta C1) showed significant differences between sites, but the profile over time was similar in both locations. delta TEWL did not differ according to anatomical location. The reason for different erythema scores on neck and forearm might be related to inherent regional variation of optical properties of the skin or to a substantial contribution of SLS-induced roughness to the readings of erythema.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Dermatitis, Irritant; Electric Conductivity; Erythema; Female; Humans; Laser-Doppler Flowmetry; Monitoring, Physiologic; Patch Tests; Skin; Sodium Dodecyl Sulfate

The intensity of the cutaneous response was assessed after application of a standard irritant to increasing areas of normal forearm skin. Twenty subjects were tested to determine the minimal irritant dose (MID) to dilutions of aqueous sodium dodecyl sulphate. Each subject was then treated under occlusion for a period of 24 h with different areas of filter paper (9, 25, 100, 225 and 400 mm2) soaked with the concentration required to give the individual's MID. At 25 and 48 h the degree of erythema was assessed using a 0-4 arbitrary scale, a 10-cm visual analogue scale (VAS) and an erythema meter. Cutaneous blood flow was measured with a laser-Doppler device and cutaneous oedema measured by pulsed A-scan ultrasound. The results at 25 and 48 h were almost identical. Both forms of visual assessment (arbitrary scale and VAS) showed an increase in perceived erythema with increasing area and this was confirmed by the erythema meter. Further area-related changes were noted with both cutaneous blood flow and ultrasound measurements.

Topics: Administration, Cutaneous; Adult; Dose-Response Relationship, Drug; Edema; Erythema; Female; Humans; Irritants; Male; Middle Aged; Patch Tests; Predictive Value of Tests; Skin; Sodium Dodecyl Sulfate; Ultrasonography

The relationship between the in vivo irritation potential of sodium lauryl sulfate (SLS) and linear alkyl benzene sulfonate (LAS) and the ability of these two surfactants to remove lipid from the stratum corneum (SC) in vitro were investigated. Either surfactant removes detectable levels of lipids only above its critical micelle concentration (CMC). At high concentrations the surfactants removed only very small amounts of cholesterol, free fatty acid, the esters of those materials, and possibly squalene. SLS and LAS have been shown, below the CMC, to bind to and irritate the SC. Thus, clinical irritation provoked by SLS or LAS is unlikely to be directly linked with extraction of SC lipid. The milder forms of irritation--dryness, tightness, roughness--may involve both surfactant binding to and denaturation of keratin as well as disruption of lipid. Our findings challenge earlier assumptions that surfactants' degreasing of the SC is involved in the induction of erythema.

Topics: Alkanesulfonates; Alkanesulfonic Acids; Cholesterol; Epidermis; Erythema; Fatty Acids, Nonesterified; Humans; Irritants; Lipid Metabolism; Lipids; Sodium Dodecyl Sulfate; Solubility

Detergent substances are important components of cleansing materials. Their detergent cleansing action may also result in skin toxicity. Methods for the evaluation of their toxic effect on the skin surface are reviewed stressing the usefulness of the soap chamber test, and newer in vitro cultural techniques. The action of detergents in promoting desquamation and removing intercorneocyte materials is also discussed. Finally, the point is made that cleansing can also be accomplished with non-detergent containing cleaners.

Topics: Detergents; Erythema; Humans; Skin; Soaps; Sodium Dodecyl Sulfate

Transepidermal water loss measurements proved to be more accurate and sensitive than visual scoring in discriminating the irritating action of detergents on the skin. Further, the baseline transepidermal water loss might be a reliable indicator of an individual's susceptibility to weak irritants.

Topics: Detergents; Erythema; Humans; Irritants; Permeability; Skin; Skin Physiological Phenomena; Sodium Dodecyl Sulfate; Surface-Active Agents; Time Factors; Water Loss, Insensible

The effect of site on the irritant dermatitis potential was studied in 10 subjects using the volar surface of the forearm. Erythema scoring and transepidermal water loss (TEWL) measurements were used to assess irritation at different levels on the forearm. A sodium lauryl sulphate (SLS 2 g/v%) solution was used as a standard irritant in a patch test procedure and on open tests. Both the erythema scores and measurements of the TEWL of exposed skin showed significant localization differences, and demonstrated that the same sites on the forearm should be used for irritancy tests and possibly physiological studies.

Topics: Adult; Body Water; Dermatitis, Contact; Erythema; Female; Forearm; Humans; Male; Middle Aged; Patch Tests; Skin Tests; Sodium Dodecyl Sulfate

Eleven subjects received patch tests with 2% sodium lauryl sulfate on a total of 34 anatomic sites. The irritant effect was monitored by visual means, laser Doppler velocimetry, and measurement of transepidermal water loss. After 1 week, repeat patch tests with 2% sodium lauryl sulfate were performed on the same site, and the effect was monitored as before. Although the skin had returned to normal or near normal before the repeat patch test, an augmented response to irritation was generally seen after the repeat patch test, particularly in transepidermal water loss, which showed an augmented response in 29 of the 34 anatomic sites. The clinical implications regarding the healing of contact irritant dermatitis are discussed.

Topics: Adolescent; Adult; Aged; Dermatitis, Contact; Erythema; Female; Humans; Irritants; Middle Aged; Patch Tests; Regional Blood Flow; Skin; Skin Tests; Sodium Dodecyl Sulfate; Ultrasonography; Water Loss, Insensible

Reactivity to repeated daily sodium lauryl sulfate (SLS) applications and patch test reactivity to SLS was studied in 23 females. Skin changes were quantified by transepidermal water loss (TEWL), dielectric water content (DEWC), laser Doppler velocimetry (LDV) and visual scoring (VS). Dermatologic histories (HS) and susceptibility to sunburn (ST) were obtained and clinical skin dryness evaluated (DS). Great interindividual variation occurred in the degrees of changes in the biophysical parameters measured: the variation was most apparent in TEWL. The subjects with HS 1 or more developed greatest TEWL increase after open SLS applications (p less than 0.05). DS showed poor correlation with SLS reactivity and only minor DEWC alterations were seen. ST showed some non-significant correlation with erythema reactivity in the patch test.

Topics: Adult; Aged; Blood Flow Velocity; Dermatitis, Contact; Erythema; Female; Humans; Irritants; Middle Aged; Patch Tests; Skin; Skin Temperature; Sodium Dodecyl Sulfate; Water Loss, Insensible

Erythema caused by occlusion of 3 concentrations of surfactant was quantified in vivo using a modified spectrophotometer. Standard chamber irritation test sites were evaluated objectively using the spectrophotometer and subjectively by trained observers. There was a good relationship between the instrumental and visual evaluations. The spectrum was analyzed and a region was chosen to optimize the sensitivity of the method.

Topics: Adult; Aged; Dermatitis, Contact; Erythema; Female; Fiber Optic Technology; Humans; Irritants; Middle Aged; Optical Fibers; Sodium Dodecyl Sulfate; Spectrophotometry; Surface-Active Agents

The effect of erythemogenic UVB irradiation and minimal erythemogenic concentration of sodium lauryl sulphate(SLS) 4% aqueous (a skin irritant) irritation, on skin water vapour loss (SVL) of 12 male Chinese volunteers was studied. The mean SVL rate of unirradiated/unirritated skin was 4.5(+/- 2.0) g water/m2/h. The mean rate for UVB irradiated skin was 6.2(+/- 3.9) g water/m2/h and the rate for SLS irritated skin was 38.5(+/ 22.3) g water/m2/h (p = 0.0003). The irritation index (defined as SVL rate of irradiated or irritated minus that of unirradiated/unirritated skin divided by SVL rate of unirradiated/unirritated skin) was significantly lower on UVB irradiated skin (0.4 +/- 0.5) than SLS irritated skin (8.1 +/- 4.2) (p = 0.0001). It appears that UVB irradiation has significant less effect on the skin barrier compared with SLS irritation. It appears that SVL measurement may be used to differentiate UVB induced erythema from irritant induced erythema.

Topics: Adult; Erythema; Humans; Male; Skin; Sodium Dodecyl Sulfate; Ultraviolet Rays; Water Loss, Insensible

The variation in human skin response to sodium lauryl sulfate (SLS) was determined with patch and open applications. Reactions in different subjects and in multiple simultaneous patch tests were compared. Skin responses were assessed with visual scoring (VS), laser Doppler velocimetry (LDV) and transepidermal water loss (TEWL). Previous open, unpatched SLS exposure decreased patch test reactivity to 1% SLS assessed with VS (p less than 0.05) or LDV (p less than 0.05). Corresponding TEWL alteration was inconstant. Variation in reactivity at different test sites in multiple simultaneous tests was considerable, though less than the variation at different test times (p less than 0.05). Inter-subject variation in test reactivity was greater than the variation between different test times or adjacent test sites. Repeated open applications and the subclinical dermatitis appear to have produced a hyporeactive state. The results suggest that non-specific skin inflammation is elicited by multiple factors, e.g., stratum corneum integrity and vascular reactivity. Their balance determines the ensuing reactions. The induced hyporeactivity may be one of many causes of false negative diagnostic patch tests.

Topics: Adult; Aged; Dermatitis, Contact; Erythema; Female; Humans; Middle Aged; Patch Tests; Rheology; Skin Tests; Sodium Dodecyl Sulfate; Water Loss, Insensible

Repeated, daily, open sodium lauryl sulfate (SLS) applications caused slight alterations in transepidermal water loss (TEWL) and dielectric water content (DEWC) in males and females. No erythema developed. Inter-individual variation in skin reactivity was demonstrated; sex-related patterns in reactivity to open cumulative irritant exposure did not exist. In patch testing with 0.5 and 1% SLS, reflecting acute irritation capacity, the reaction pattern, assessed by TEWL, DEWC, laser Doppler velocimetry (LDV) and visual scoring (VS), differed from that induced by open, cumulative SLS irritation. Again, inter-individual variation in the reactivity was demonstrated; significant sex-related differences did not develop. Individual reactivity showed considerable variation in acute and cumulative irritant response and was greater than the sex-related variation. We did not identify responses demonstrating that women have delicate (easily irritated) skin, nor that males have "tougher" skin than females.

Topics: Adolescent; Adult; Body Water; Erythema; Female; Humans; Irritants; Male; Middle Aged; Patch Tests; Regional Blood Flow; Rheology; Sex Factors; Skin; Sodium Dodecyl Sulfate; Water Loss, Insensible

Inflammation was induced on the forearms of volunteers by twenty-four closed patch tests to either the irritant 10% sodium lauryl sulfate (SLS) or Toxicodendron extract. Each chemical was tested at eight sites on the ventral forearms of each volunteer in order to assess the variability of response among test sites in individual subjects. Inflammation was assessed about 10 minutes after patch tests were removed. The degree of inflammation elicited by both Toxicodendron and SLS was variable among subjects, but variation among individual test sites was much more marked in subjects tested with SLS (p less than 0.002). The marked variability of responses to irritation that occur in any single subject may explain why irritant patch test responses do not reliably identify the irritation-prone individual.

Topics: Adolescent; Adult; Allergens; Body Surface Area; Dermatitis, Contact; Dermatitis, Toxicodendron; Drug Evaluation, Preclinical; Edema; Erythema; Female; Forearm; Humans; Irritants; Male; Patch Tests; Plant Extracts; Plants, Toxic; Skin; Sodium Dodecyl Sulfate; Time Factors; Toxicodendron

Patch tests with aqueous solutions of the irritating detergent sodium lauryl sulfate (SLS) elicit varying degrees of inflammation from subject to subject and from site to site. For an investigation of the causes of this variability, two patch tests with 10% aqueous solutions of SLS were applied to adjacent areas of ventral forearm skin of eighteen volunteers. In one test the water vehicle was allowed to evaporate from the patch test unit before the patches were applied. After 22 hours the patch tests were removed, and 2 hours later the degree of inflammation was graded. Less inflammation was present at the site of the dry patch test in fifteen of eighteen subjects, and the score of inflammation between each pair was significantly less at the dry patch test site (p less than 0.001). These studies show that evaporation of water from aqueous solutions can influence the irritating potential of SLS on human skin.

Topics: Adult; Chemistry, Pharmaceutical; Dermatitis, Contact; Drug Evaluation, Preclinical; Edema; Erythema; Female; Forearm; Humans; Irritants; Male; Patch Tests; Pharmaceutical Vehicles; Skin; Sodium Dodecyl Sulfate; Time Factors; Volatilization; Water

Groups of guinea pigs were sensitized with a 0.1% solution of dinitrochlorobenzene (DNCB) by the Draize intracutaneous method. The course of the induction process, the influence of the vehicles used and the extent to which the reactions are amenable to assessment according to objective criteria were examined. The sensitivity of the standardized Draize test was then compared with that of various other sensitization techniques, including: The intracutaneous test with adjuvant (optimization test) The maximization test according to Magnusson & Kligman (1969) The epidermal sensitization test The epidermal sensitization test with prior irritation of the contact site (by croton oil or sodium lauryl sulphate). Comparison of these methods revealed that either the additional application of adjuvant or prior irritation of the contact site augmented the degree of sensitization of DNCB just as greatly as the simultaneous use of adjuvant and prior irritation of the skin, (maximization test). The improved sensitization methods, and in particular the standardized optimization test, may prove to be of particular value for the study of so-called weak allergens.

Topics: Animals; Dermatitis, Contact; Dinitrochlorobenzene; Erythema; Guinea Pigs; Injections, Intradermal; Nitrobenzenes; Oils; Skin; Skin Tests; Sodium Dodecyl Sulfate

Enterotoxin produced by a sporulating culture of Clostridium perfringens type C, which had been isolated from a case of severe necrotic enteritis, was purified. The molecular weight was estimated to be 36,000 by gel chromatography on Sephadex G-100 and 33,400 by ultracentrifugation. The sedimentation coefficient S20,W was 2.92. The toxin protein exhibited unusual behavior on sodium dodecyl sulfate gels, and toxin aggregates having molecular weights of 68,000, 85,000, 105,000, and 140,000 were obtained. The purified enterotoxin often separated, apparently due to slight charge differences, into two protein bands on 7% polyacrylamide gels. Electrofocusing of enterotoxin on polyacrylamide gels gave an approximate isoelectric point of 4.3, with the enterotoxin being fractionated into four distinct protein bands. The specific toxicity of the enterotoxin was about 1,900 mouse mean lethal doses per mg of calculated nitrogen. The data obtained indicate that the enterotoxin from C. perfringens type C is identical in most respects to that obtained from type A strains. Whether or not this toxin plays a role in the necrotic enteritis caused by type C strains is unknown at present.

Topics: Bacterial Proteins; Bacteriological Techniques; Centrifugation, Density Gradient; Clostridium perfringens; Dextrans; Electrophoresis, Disc; Enterotoxins; Erythema; Immune Sera; Immunodiffusion; Immunoelectrophoresis; Isoelectric Focusing; Molecular Weight; Neutralization Tests; Skin Tests; Sodium Dodecyl Sulfate

A 5 h, semi-occlusive human patch test repeated daily for 5 days, was modified for use in the rabbit Using this method, the relative irritancy of three cosmetic samples of known human irritancy was determined in the rabbit. In addition, attention was paid to assessment methods and a detailed histological scoring system is described as well as two methods of visual assessment. In order to compare the effectiveness of these methods, the reaction to a series of concentrations of sodium lauryl sulphate was examined. All three assessment methods gave similar results and the merits of combining histological and visual assessment are discussed.

Topics: Acanthosis Nigricans; Animals; Cosmetics; Edema; Erythema; Female; Models, Biological; Parakeratosis; Patch Tests; Rabbits; Skin Tests; Sodium Dodecyl Sulfate; Ulcer