salicylates and benzyl-salicylate

A toxicologic and dermatologic review of benzyl salicylate when used as a fragrance ingredient is presented.

Topics: Allergens; Animals; Consumer Product Safety; Dose-Response Relationship, Drug; Humans; Irritants; Mutagenicity Tests; Mutagens; Perfume; Photosensitizing Agents; Risk Assessment; Salicylates; Skin; Skin Irritancy Tests; Skin Tests

Contact sensitization is frequent among patients with frontal fibrosing alopecia (FFA) (52%-76%).. To evaluate the frequency of sensitization/photosensitization in an FFA population.. A population of FFA patients were patch tested (Spanish Contact Dermatitis Research Group [GEIDAC] baseline; cosmetic and fragrance series), and photopatch tested (sunscreen series).. Thirty-six patients (mean age: 64.6 years; 35/36: women) were studied. A history of dermatitis was recorded in 69.4% (frequently involving the face). Overall, 80.5% patients showed positive patch-test reactions. The most frequently positive allergens were nickel sulfate (25%), benzyl salicylate (22%), gallates (16.6%), propolis (16.6%), and limonene hydroperoxides (13.8%). Benzyl salicylate was likely relevant to the dermatitis (labeled on personal care products and most patients reporting clinical improvement with allergen avoidance). Patch tests with sunscreens showed positive reactions to 11 materials (five patients). Photopatch tests were positive in one case.. We speculate a possible relationship between sensitization to benzyl salicylate and FFA. Hypothetically, the most likely explanation is that sensitization to benzyl salicylate involving FFA patients is a consequence of increased exposure to it. It is unclear whether allergen avoidance may impact the prognosis of alopecia. However, it seems to significantly improve the patients´ quality of life by lessening dermatitis and pruritus.

Topics: Adult; Aged; Aged, 80 and over; Allergens; Alopecia; Cosmetics; Dermatitis, Allergic Contact; Dermatitis, Photoallergic; Female; Humans; Male; Middle Aged; Odorants; Pruritus; Quality of Life; Retrospective Studies; Salicylates; Spain; Sunscreening Agents

We investigated the larvicidal potential of 10 plant essential oils (EOs) against the Asian tiger mosquito Aedes albopictus. Among the EOs, larvicidal activity against Ae. albopictus was strongest in those derived from massoia (Massoia aromatica) and nutmeg (Myristica fragrans). Larvicidal activities of massoia and nutmeg EOs against Ae. albopictus were 95.0% and 85.0% at 50 μg/mL, respectively. A total of 4 and 14 compounds were identified from massoia and nutmeg, respectively, and two massoia lactones, C10 and C12, were isolated from massoia EO. Among the identified compounds, benzyl salicylate, terpinolene, C12 massoia lactone, sabinene, benzyl benzoate, methyl eugenol, and C10 massoia lactone exhibited the strong larvicidal activity. Cellulose nanocrystal (CNC)-stabilized Pickering emulsions of massoia and nutmeg EOs were developed to overcome the insolubility of EOs in water. CNC/massoia and CNC/nutmeg emulsions were stable for at least 10 days, and larvicidal activities of CNC/massoia PE and CNC/nutmeg were higher than those of crude massoia and nutmeg EOs. This study presents a CNC-stabilized PE, a suitable formulation for EOs, as a potential larvicide against Ae. albopictus.

Topics: Aedes; Animals; Benzoates; Cellulose; Chromatography, Gas; Cyclohexane Monoterpenes; Emulsions; Eugenol; Insecticides; Lactones; Larva; Myristica; Nanoparticles; Oils, Volatile; Plant Oils; Salicylates; Solubility

Topics: Alopecia; Dermatitis, Allergic Contact; Humans; Lichen Planus; Salicylates

Topics: Alopecia; Dermatitis, Allergic Contact; Humans; Lichen Planus; Salicylates

To date, all human studies of mass-casualty decontamination for chemical incidents have relied on the collection and analysis of external samples, including skin and hair, to determine decontamination efficacy. The removal of a simulant contaminant from the surface of the body with the assumption that this translates to reduced systemic exposure and reduced risk of secondary contamination has been the main outcome measure of these studies. Some studies have investigated systemic exposure through urinary levels of simulant metabolites. The data obtained in these studies were confounded by high background concentrations from dietary sources. The unmetabolized simulants have never been analyzed in urine for the purposes of decontamination efficacy assessment.. Urinary simulant analysis could obviate the need to collect skin or hair samples during decontamination trials and provide a better estimate of both decontamination efficacy and systemic exposure. The study objective therefore was to determine whether gross skin contamination as part of a decontamination study would yield urine levels of simulants sufficient to evaluate systemic availability free from dietary confounders.. In this study, a gas chromatography-tandem mass spectrometry method was developed for the analysis of two chemical simulants, methyl salicylate (MeS) and benzyl salicylate (BeS), in urine. An extraction and sample clean-up method was validated, enabling quantitation of these simulants in urine. The method was then applied to urine collected over a 24-hour period following simulant application to the skin of volunteers.. Both MeS and BeS were present in all urine samples and were significantly increased in all post-application samples. The MeS levels peaked one hour after skin application. The remaining urinary levels were variable, possibly due to additional MeS exposures such as inhalation. In contrast, the urinary excretion pattern for BeS was more typical for urinary excretion curves, increasing clearly above baseline from four hours post-dose and peaking between 12.5 and 21 hours, a pattern consistent with dermal absorption and rapid excretion.. The authors propose BeS is a useful simulant for use in decontamination studies and that its measurement in urine can be used to model systemic exposures following skin application and therefore likely health consequences.

Topics: Adult; Chemical Hazard Release; Decontamination; Female; Gas Chromatography-Mass Spectrometry; Healthy Volunteers; Humans; Male; Mass Casualty Incidents; Salicylates; Urinalysis

Herein is reported the first total synthesis of benzyl salicylate and benzyl gentisate glucosides present in various plant species, in particular the

Topics: Benzyl Compounds; Gentisates; Glycosides; Molecular Structure; Populus; Salicylates

The decontamination of exposed persons is a priority following the release of toxic chemicals. Efficacious decontamination reduces the risk of harm to those directly affected and prevents the uncontrolled spread of contamination. Human studies examining the effectiveness of emergency decontamination procedures have primarily focused on decontaminating skin, with few examining the decontamination of hair and scalp. We report the outcome of two studies designed to evaluate the efficacy of current United Kingdom (UK) improvised, interim and specialist mass casualty decontamination protocols when conducted in sequence. Decontamination efficacy was evaluated using two chemical simulants, methyl salicylate (MeS) and benzyl salicylate (BeS) applied to and recovered from the hair of volunteers. Twenty-four-hour urinary MeS and BeS were measured as a surrogate for systemic bioavailability. Current UK decontamination methods performed in sequence were partially effective at removing MeS and BeS from hair and underlying scalp. BeS and MeS levels in urine indicated that decontamination had no significant effect on systemic exposure raising important considerations with respect to the speed of decontamination. The decontamination of hair may therefore be challenging for first responders, requiring careful management of exposed persons following decontamination. Further work to extend these studies is required with a broader range of chemical simulants, a larger group of volunteers and at different intervention times.

Topics: Adult; Decontamination; Female; Hair; Healthy Volunteers; Humans; Male; Mass Casualty Incidents; Salicylates; Scalp; United Kingdom

Topics: Adult; Chemical Warfare Agents; Decontamination; Female; Gas Chromatography-Mass Spectrometry; Hair; Humans; Isotope Labeling; Male; Middle Aged; Reproducibility of Results; Salicylates; Skin; Tandem Mass Spectrometry

Pigmented contact dermatitis (PCD) is a noneczematous variant of allergic contact dermatitis, and benzyl salicylate is one of its causes. This type of PCD shows nonlichenoid interface dermatitis with pigment incontinence. We aimed to characterize the earliest histopathological changes of this reaction. A 51-year-old man presented with persistent facial eruption composed of hyperpigmented and hypopigmented macules due to exposure to benzyl salicylate present in his aftershave. The biopsies obtained from hyperpigmented and hypopigmented macules, and from the positive patch test site to benzyl salicylate, showed a nonlichenoid focal vacuolar interface dermatitis with mononuclear cells in the papillary dermis and around the pilosebaceous units, along with melanophages. A MART-1 immunostain showed intact melanocytes in all 3 biopsies. A Fontana-Masson stain demonstrated intact melanin in the basal cell layer of a facial hyperpigmented macule and the patch test site, but melanin was reduced in the biopsy taken from a hypopigmented facial macule. There were more epidermal and dermal CD1a+ Langerhans cells in the patch test biopsy than in the other 2 biopsies. Most of the mononuclear cells were CD3+. The CD4+ to CD8+ ratio was approximately 1:1 in the facial macules; yet, CD4+ cells outnumbered CD8+ cells in the patch test biopsy. There were a few TIA-1+ cells in all 3 biopsies. In conclusion, the earliest histopathological and immunophenotypical events in PCD due to benzyl salicylate are similar to those of longer-standing lesions, i.e., a nonlichenoid focal interface dermatitis involving the epidermis and pilosebaceous unit, along with dermal melanophages.

Topics: Dermatitis, Allergic Contact; Humans; Immunohistochemistry; Male; Middle Aged; Patch Tests; Salicylates

Over 4000 small chemicals have been identified as allergens capable of inducing skin sensitization. Many sensitizers are hypothesized to act as haptens producing novel antigens, which can be presented to T cells by human leukocyte antigens (HLAs). Recent studies suggest that some chemical allergens use hapten-independent mechanisms.. To determine whether molecular docking can identify HLA molecules that bind skin-sensitizing chemical allergens.. Structural models of HLA molecules were used as the basis for molecular docking of 22 chemical allergens. Allergens predicted to bind HLA-B*57:01 were tested for their ability to stimulate T cells by the use of proliferation and interferon-gamma enzyme-linked immunospot assays.. Chemical allergens that did not satisfy the criteria for hapten activity in vitro were predicted to bind more strongly to common HLA isoforms than those with known hapten activity. HLA-B*57:01, which is an HLA allele required for drug hypersensitivity reactions, was predicted to bind several allergens, including benzyl benzoate, benzyl cinnamate, and benzyl salicylate. In in vitro T cell stimulation assays, benzyl salicylate and benzyl cinnamate were found to stimulate T cell responses from HLA-B*57:01 carriers.. These data suggest that small-molecule skin sensitizers have the potential to interact with HLA, and show that T cell-based in vitro assays may be used to evaluate the immunogenicity of skin-sensitizing chemicals.

Topics: Allergens; Benzoates; Benzyl Compounds; Cell Proliferation; Cells, Cultured; Cinnamates; Dermatitis, Allergic Contact; Haptens; HLA-B Antigens; Humans; Lymphocyte Activation; Molecular Docking Simulation; Molecular Structure; Perfume; Salicylates; T-Lymphocytes

Topics: Aged; Dermatitis, Allergic Contact; Facial Dermatoses; Female; Hair Preparations; Humans; Patch Tests; Salicylates

Benzyl salicylate is used as a fragrance ingredient and an ultraviolet light absorber, but its toxicity is unknown. Therefore, toxicity tests and hazard classification were conducted for screening assessment under the Japanese Chemical Substances Control Law. Benzyl salicylate was found to be non-genotoxic in vitro based on the chromosomal aberration test using Chinese hamster lung cells. However, the combined repeated-dose and reproductive/developmental screening toxicity test, in which male and female rats were administered benzyl salicylate by gavage at 0, 30, 100, or 300 mg/kg/day for 42 and 41-46 days, respectively, from 14 days before mating until postnatal Day 4, showed that repeated doses had major effects on the thymus, liver, epididymis, and femur at 100 and/or 300 mg/kg/day. Furthermore, although benzyl salicylate had no effect on the estrus cycle, fertility, corpus lutea, or implantation rate, embryonic resorption, offspring mortality, and neural tube defects were observed at 300 mg/kg/day, and the offspring had lower body weights at 30 and 100 mg/kg/day, suggesting teratogenicity similar to other salicylates. Based on the developmental toxicity, this chemical was classified as hazard class 2, with a lowest observed adverse effect level (LOAEL) of 30 mg/kg/day and a D-value of 0.003 mg/kg/day.

Topics: Animals; Cell Line; Cricetulus; Dose-Response Relationship, Drug; Embryo Loss; Embryo, Mammalian; Female; Fibroblasts; Lung; Male; Mutagenicity Tests; Neural Tube Defects; Odorants; Rats, Sprague-Dawley; Reproduction; Salicylates; Toxicity Tests

Topics: Chronic Disease; Cosmetics; Dermatitis, Allergic Contact; Edema; Erythema; Eyelid Diseases; Facial Dermatoses; Female; Humans; Middle Aged; Pruritus; Salicylates

A methodology based on headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) determination was developed for the monitoring and evaluation of the removal efficiency of 16 common fragrance allergens and two polycyclic musks in wastewater treatment plants (WWTPs). An experimental design with a full factorial model was applied to evaluate the effects of the experimental parameters on the extraction (e.g., salt content, time and extraction temperature). After determining the optimum conditions (2.4 g NaCl, 45 min at 90 °C), an external calibration was performed and quality parameters of the proposed method were evaluated. Method detection limits in the range of 0.01-1.7 μg L(-1) were obtained. Satisfactory inter-day precision values between 4% and 23% (n=5) were obtained for most compounds. The method was applied to the monitoring of the target analytes in samples from two WWTPs. Seven target compounds were detected at the primary effluent of both plants at μg L(-1) levels. Limonene, linalool and eugenol were quantitatively eliminated during the secondary treatments of both WWTPs, while lilial, benzyl salicylate, galaxolide, and tonalide were still detected at the effluent waters.

Topics: Acyclic Monoterpenes; Aldehydes; Allergens; Benzopyrans; Cyclohexenes; Eugenol; Fatty Acids, Monounsaturated; Gas Chromatography-Mass Spectrometry; Limonene; Monoterpenes; Odorants; Perfume; Salicylates; Solid Phase Microextraction; Terpenes; Tetrahydronaphthalenes; Wastewater; Water Pollutants, Chemical

Salicylates are used as fragrance and flavor ingredients for foods, as UV absorbers and as medicines. Here, we examined the hydrolytic metabolism of phenyl and benzyl salicylates by various tissue microsomes and plasma of rats, and by human liver and small-intestinal microsomes. Both salicylates were readily hydrolyzed by tissue microsomes, predominantly in small intestine, followed by liver, although phenyl salicylate was much more rapidly hydrolyzed than benzyl salicylate. The liver and small-intestinal microsomal hydrolase activities were completely inhibited by bis(4-nitrophenyl)phosphate, and could be extracted with Triton X-100. Phenyl salicylate-hydrolyzing activity was co-eluted with carboxylesterase activity by anion exchange column chromatography of the Triton X-100 extracts of liver and small-intestinal microsomes. Expression of rat liver and small-intestinal isoforms of carboxylesterase, Ces1e and Ces2c (AB010632), in COS cells resulted in significant phenyl salicylate-hydrolyzing activities with the same specific activities as those of liver and small-intestinal microsomes, respectively. Human small-intestinal microsomes also exhibited higher hydrolyzing activity than liver microsomes towards these salicylates. Human CES1 and CES2 isozymes expressed in COS cells both readily hydrolyzed phenyl salicylate, but the activity of CES2 was higher than that of CES1. These results indicate that significant amounts of salicylic acid might be formed by microsomal hydrolysis of phenyl and benzyl salicylates in vivo. The possible pharmacological and toxicological effects of salicylic acid released from salicylates present in commercial products should be considered.

Topics: Animals; Carboxylic Ester Hydrolases; Flavoring Agents; Humans; Hydrolysis; Intestine, Small; Liver; Male; Microsomes; Rats; Rats, Sprague-Dawley; Salicylates

Disinfection of swimming pool water is essential to inactivate pathogenic microorganisms. However chlorine based disinfectants, the most commonly used, are known to lead to the formation of disinfection by-products (DBPs), some of which have been associated with adverse health effects. Precursors of DBPs include the organic matter present in the water used to fill the swimming pool, human body fluids and personal care products (PCPs) used by swimmers and bathers. The increased use, in the last years, of PCPs lead to an increased concern about the fate of PCPs in swimming pool waters and potential health risks of formed DBPs. In this study, the chemical transformations of two salicylates, benzyl salicylate (BzS) and phenyl salicylate (PS), incorporated in several PCPs, in chlorinated water were investigated. High-performance liquid chromatography (HPLC) with UV-diode-array detection (HPLC-UV-DAD) was used to follow the reaction kinetics and HPLC with mass spectrometry (HPLC-MS) was used to tentatively identify the major transformation by-products. Under the experimental conditions used in this work both salicylates reacted with chlorine following pseudo-first order kinetics: rate constant k = (0.0038 ± 0.0002) min(-1) and half-life t1/2 = (182 ± 10) min for BzS and rate constant k = (0.0088 ± 0.0005) min(-1) and half-life t1/2 = (79 ± 4) min for PS (mean ± standard deviation). The reactions of the two salicylates in chlorinated water led to the formation of DBPs that were tentatively identified as mono- and dichloro- substituted compounds. Most probably they result from an electrophilic substitution of one or two hydrogen atoms in the phenolic ring of both salicylates by one or two chlorine atoms.

Topics: Chlorine; Chromatography, High Pressure Liquid; Disinfectants; Disinfection; Mass Spectrometry; Salicylates; Swimming Pools; Water Pollutants, Chemical; Water Pollution, Chemical

Many different types of samples have been analyzed in the literature using plasma-based ambient mass spectrometry sources; however, comprehensive studies of the important parameters for analysis are only just beginning. Here, we investigate the effect of the sample form and surface temperature on the signal intensities in plasma-assisted desorption ionization (PADI). The form of the sample is very important, with powders of all volatilities effectively analyzed. However, for the analysis of thin films at room temperature and using a low plasma power, a vapor pressure of greater than 10(-4) Pa is required to achieve a sufficiently good quality spectrum. Using thermal desorption, we are able to increase the signal intensity of less volatile materials with vapor pressures less than 10(-4) Pa, in thin film form, by between 4 and 7 orders of magnitude. This is achieved by increasing the temperature of the sample up to a maximum of 200 °C. Thermal desorption can also increase the signal intensity for the analysis of powders.

Topics: Algorithms; Butylated Hydroxytoluene; Mass Spectrometry; Parabens; Phenylalanine; Powders; Salicylates; Temperature; Vapor Pressure

Topics: Administration, Cutaneous; Aged; Cosmetics; Dermatitis, Contact; Female; Humans; Hydroquinones; Hyperpigmentation; Patch Tests; Salicylates; Skin; Skin Cream; Skin Pigmentation; Sunscreening Agents; Treatment Outcome

Propolis is a beehive product popular in natural medicine thanks to its noteworthy properties. Propolis is non-toxic but is responsible for allergic reactions in sensitive individuals. In this paper, we propose a new gas chromatography-mass spectrometry (GC-MS) analytical methodology for the quantitative analysis of two allergenic esters in propolis specimens, benzyl salicylate and benzyl cinnamate, and test it on specimens from different locations of central Italy. We also present the results obtained in the chemical characterization of the same specimens. The characterization showed that the resin fractions of all of the specimens are of poplar origin.

Topics: Allergens; Antigens, Plant; Benzyl Compounds; Cinnamates; Esters; Gas Chromatography-Mass Spectrometry; Italy; Propolis; Salicylates

The performance of the dispersive liquid-liquid microextraction (DLLME) technique for the determination of eight UV filters and a structurally related personal care species, benzyl salicylate (BzS), in environmental water samples is evaluated. After extraction, analytes were determined by gas chromatography combined with mass spectrometry detection (GC-MS). Parameters potentially affecting the performance of the sample preparation method (sample pH, ionic strength, type and volume of dispersant and extractant solvents) were systematically investigated using both multi- and univariant optimization strategies. Under final working conditions, analytes were extracted from 10 mL water samples by addition of 1 mL of acetone (dispersant) containing 60 μL of chlorobenzene (extractant), without modifying either the pH or the ionic strength of the sample. Limits of quantification (LOQs) between 2 and 14 ng L(-1), inter-day variability (evaluated with relative standard deviations, RSDs) from 9% to 14% and good linearity up to concentrations of 10,000 ng L(-1) were obtained. Moreover, the efficiency of the extraction was scarcely affected by the type of water sample. With the only exception of 2-ethylhexyl-p-dimethylaminobenzoate (EHPABA), compounds were found in environmental water samples at concentrations between 6 ± 1 ng L(-1) and 26 ± 2 ng mL(-1).

Topics: Chemical Fractionation; Environmental Monitoring; Gas Chromatography-Mass Spectrometry; Rivers; Salicylates; Sensitivity and Specificity; Sunscreening Agents; Swimming Pools; Time Factors; Water Pollutants, Chemical

Benzyl salicylate, benzyl benzoate and butylphenylmethylpropional (Lilial) are added to bodycare cosmetics used around the human breast. We report here that all three compounds possess oestrogenic activity in assays using the oestrogen-responsive MCF7 human breast cancer cell line. At 3 000 000-fold molar excess, they were able to partially displace [(3)H]oestradiol from recombinant human oestrogen receptors ERalpha and ERbeta, and from cytosolic ER of MCF7 cells. At concentrations in the range of 5 x 10(-5) to 5 x 10(-4 )m, they were able to increase the expression of a stably integrated oestrogen-responsive reporter gene (ERE-CAT) and of the endogenous oestrogen-responsive pS2 gene in MCF7 cells, albeit to a lesser extent than with 10(-8 )m 17beta-oestradiol. They increased the proliferation of oestrogen-dependent MCF7 cells over 7 days, which could be inhibited by the antioestrogen fulvestrant, suggesting an ER-mediated mechanism. Although the extent of stimulation of proliferation over 7 days was lower with these compounds than with 10(-8 )m 17beta-oestradiol, given a longer time period of 35 days the extent of proliferation with 10(-4 )m benzyl salicylate, benzyl benzoate or butylphenylmethylpropional increased to the same magnitude as observed with 10(-8 )m 17beta-oestradiol over 14 days. This demonstrates that benzyl salicylate, benzyl benzoate and butylphenylmethylpropional are further chemical components of cosmetic products which give oestrogenic responses in a human breast cancer cell line in culture. Further research is now needed to investigate whether oestrogenic responses are detectable using in vivo models and the extent to which these compounds might be absorbed through human skin and might enter human breast tissues.

Topics: Aldehydes; Benzoates; Binding, Competitive; Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Cosmetics; Cytosol; Dose-Response Relationship, Drug; Estradiol; Estrogen Receptor alpha; Estrogen Receptor beta; Estrogen Receptor Modulators; Female; Humans; Ligands; Molecular Structure; Protein Binding; Recombinant Proteins; Reverse Transcriptase Polymerase Chain Reaction; Salicylates; Transfection

Starting point of the present paper was the result of a virtual screening using the open conformation of the large extracellular loop (LEL) of the CD81-receptor (crystal structure: PDB-ID: 1G8Q). After benzyl salicylate had been experimentally validated to be a moderate inhibitor of the CD81-LEL-HCV-E2 interaction, further optimization was performed and heterocyclic-substituted benzyl salicylate derivatives were synthesized. The compounds were tested for their ability to inhibit the interaction of a fluorescence-labeled antibody to CD81-LEL using HUH7.5 cells. No compound showed an increase concerning the inhibition of the protein-protein interaction compared to benzyl salicylate.

Topics: Antigens, CD; Antiviral Agents; Cell Line; Drug Evaluation, Preclinical; Humans; Protein Binding; Salicylates; Structure-Activity Relationship; Tetraspanin 28; Viral Envelope Proteins

UV-absorbing chemicals (UV filters) are widely used for protection against UV radiation in sunscreens and in a variety of cosmetic products and materials. Depending on the breadth and factor of UV protection, they are added as single compounds or as a combination thereof. Some UV filters have estrogenic activity, but their activity and interactions in mixtures are largely unknown. In this work, we analyzed 8 commonly used UV filters, which are pure or partial hERalpha agonists, for their estrogenic activity in equieffective mixtures in a recombinant yeast assay carrying the human estrogen receptor alpha (hERalpha). Mixtures of two, four and eight UV filters alone, or in combination with 17 beta estradiol (E2), were assessed at different effect levels and no-observed-effect-concentrations (NOEC). Predictions of the joint effects of these mixtures were calculated by employing the concentration addition (CA) and independent action (IA) model. Most binary mixtures comprising of pure hERalpha agonists showed a synergistic activity at all mixture combinations. Only in combination with benzophenone-1, antagonistic activity was observed at some effect levels. All mixtures of four or eight, pure or pure and partial hERalpha agonists, alone or including E2, showed synergistic activity at concentrations giving an increase of 10% of basal activity (BC10). This occurred even at concentrations that were at the NOEC level of each single compound. Hence, there were substantial mixture effects even though each UV filter was present at its NOEC level. These results show that significant interactions occur in UV filter mixtures, which is important for the hazard and risk assessments of these personal care products.

Topics: Benzocaine; Benzophenones; Dose-Response Relationship, Drug; Drug Synergism; Estrogen Receptor alpha; Estrogens; No-Observed-Adverse-Effect Level; Recombinant Proteins; Risk Assessment; Saccharomyces cerevisiae; Salicylates; Sunscreening Agents

The loss of the plasticizers dibutylphthalate, butylphthalylbutyl glycolate, benzylbenzoate, methylsalicylate, and benzylsalicylate from four soft lining materials was measured. A 0.1% aqueous solution of triton X-100, reduced was used as immersion medium, since the solubility of plasticizer in this medium was close to that of saliva. The loss of plasticizer was monitored up to 30 d after mixing. For two of the materials, the average amount of leached dibutylphthalate within the first day exceeded the proposed tolerable daily intake (TDI) by about 11 and 32 times, respectively, for an average adult person. Similarly, for these two materials, the average daily amount within the first 30 d of leached dibutylphthalate was 2.2 and 6.6 times larger, respectively, than the TDI limit. The cumulative amount leached over 30 d for each of the four materials was 128-253 mg plasticizer g(-1). The results indicate the need for further biological evaluations of these products.

Topics: Adult; Benzoates; Dental Restoration, Temporary; Denture Liners; Denture, Complete; Humans; Linear Models; Materials Testing; Maximum Tolerated Dose; Octoxynol; Phthalic Acids; Plasticizers; Salicylates; Saliva, Artificial

Variation in the components of soft lining materials, i.e. the size of polymer particles, the ethyl alcohol content of the liquids and the type of plasticizer, were investigated with respect to their effects on the growth and colonization of Candida albicans. Inhibitory effects on fungal growth and/or acid production were found to vary depending upon the components of soft lining materials. In particular, two plasticizers, benzyl benzoate (BB) and benzyl salicylate (BS), significantly decreased the growth rate, whereas the size of polymer particle had little effect on fungal growth. Ethyl alcohol content of liquid significantly affected the fungal growth and/or acid production depending upon the plasticizer used. For instance, in the case of BS, the antifungal effect was related to ethyl alcohol contents, whereas a reverse effect was observed with benzyl n-butyl phthalate (BBP). Further examination using scanning electron microscopy revealed that Candida blastospores colonized lining materials in the following two ways depending on the plasticizers used. On the BS and dibutyl phthalate (DBP) specimen, the blastospore of this yeast associated loosely, whereas, in the case of BB, BBP and butyl phthalyl butyl glycorate (BPBG), fungal blastospore tightly and invasively colonized onto the specimens. These results clearly demonstrated a relationship between components of soft lining materials and fungal growth and colonization.

Topics: Analysis of Variance; Antifungal Agents; Benzoates; Biofilms; Candida albicans; Denture Liners; Dibutyl Phthalate; Ethanol; Hydrogen-Ion Concentration; Methacrylates; Phthalic Acids; Plasticizers; Salicylates; Spores, Fungal; Statistics, Nonparametric; Wettability

An evaluation has been made of the soft polymer gel systems of the type used as prosthodontic short-term denture-lining materials. The purpose of the study was to determine the effect upon gel strength and gelation time produced by variations in the composition of the plasticizer liquids. Poly(ethylmethacrylate) co-polymers were mixed with combinations of ethyl alcohol and the esters dibutyl phthalate (DBP), butylphthalyl butylglycolate (BPBG), and benzyl salicylate (BS). The relative rate of gelation of plasticizer polymer compositions was obtained by means of a reciprocating rheometer. The gelation rate was found to increase rapidly with an increase in the ethyl alcohol content. Significantly shorter gelation times were also found with liquids containing the lower-molecular-weight esters. A linear relationship was found between the ethyl alcohol content and the log of the gelation time. The higher-molecular-weight esters produced the strongest gel. A linear relationship was found between the gelation (log) times and the seven-day puncture strength. The ratio of polymer to plasticizer liquid was found to have a very significant influence upon the puncture strength and gelation time. Molecular weight or molecular volume of the ester plasticizers was found to have a greater influence on gel formation than the cohesive energy parameter. The strong polar bonding of ethyl alcohol was found to have a significant influence on both the rate of gel formation and the subsequent gel strength. The data indicate that controlled variations in the characteristics of plasticity and gel strength of dental soft polymer systems can be made to suit different clinical prosthodontic requirements.

Topics: Chemical Phenomena; Chemistry, Physical; Dibutyl Phthalate; Ethanol; Gels; Hydrogen Bonding; Methylmethacrylates; Plasticizers; Polymers; Rheology; Salicylates; Stress, Mechanical; Time Factors

The potential of benzyl salicylate, an important fragrance and flavour ingredient, to induce hypersensitivity or to elicit reactions to pre-existing hypersensitivity in the general population was evaluated by analysing patch-test data. Results obtained from fragrance and formulator companies for a total of 10,538 patch tests on benzyl salicylate alone, on a variety of household and personal care consumer products and on fragrance blends containing benzyl salicylate were analysed as part of this survey. No induced or elicited responses directly attributable to benzyl salicylate were observed in the 35 patch tests on benzyl salicylate alone, or in the 10,503 patch tests on consumer products or fragrance blends containing benzyl salicylate. The highest concentration of benzyl salicylate tested in the consumer-product tests was 2 X 10(-1)%, and benzyl salicylate alone was tested at 10% in ethanol. This study indicates that benzyl salicylate has a very low potential to induce hypersensitivity ('induced' reactions) or to elicit reactions presumably attributable to pre-existing sensitization ('elicited' reactions) and thus supports the safe use of benzyl salicylate in consumer products and fragrance blends.

Topics: Dermatitis, Contact; Humans; Patch Tests; Salicylates

Topics: Camphor; Drug Therapy; Humans; Injections; Injections, Intra-Articular; Knee Joint; Oils; Osteoarthritis; Salicylates