salicylates and hexyl-salicylate

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

Topics: Allergens; Animals; Consumer Product Safety; Dose-Response Relationship, Drug; Humans; Irritants; Perfume; Risk Assessment; Salicylates; Skin; Skin Absorption; Skin Irritancy Tests; Skin Tests; Toxicity Tests

Skin irritation tests using reconstructed human epidermis (RhE) employ viability as an endpoint, but color interference or borderline results are often problematic. We examined whether the cytology of cells from treated RhE could determine skin irritancy. Six chemicals (three irritants; DnP, 1-B, PH, three non-irritants; DP, APA, HS) were evaluated in a RhE, Keraskin™. DP, HS, and PH were clearly classified with viability, but DnP, 1-B, and APA were often falsely determined, due to borderline values falling near the cutoff, 50%. In histology, the tissues treated with DnP, 1-B, and PH showed erosion of the stratum corneum, vacuolization, and necrosis in the basal layer. DP- and HS-treated tissues showed relatively normal morphology but APA induced necrosis similar to irritants. Cytology revealed that DnP, 1-B or PH depleted cells and induced irregular and abnormal cell shapes. In contrast, relatively regular and normal shapes and clear distinction between the nucleus and cytoplasm was observed for DP, APA and HS. To further confirm it, additional 10 substances, including false positives from OECD TG 439, were tested. Overall (16 substances in total), cytology: total area predicted the skin irritancy of test chemicals with the highest accuracy (87.5%) followed by cytology: cell count (81.3%), histology (75%) and viability (68.8%), confirming the utility of cytology as an alternative endpoint in the skin irritation test using RhE.

Topics: Animal Testing Alternatives; Disulfides; Epidermal Cells; Epidermis; Glycolates; Humans; Hydrocarbons, Halogenated; Hydroxides; Irritants; Phthalic Acids; Potassium Compounds; Salicylates; Skin Irritancy Tests

Topics: Cinnamates; Cosmetics; Dermatitis, Allergic Contact; Dioxolanes; Humans; Odorants; Patch Tests; Salicylates

Thermal imaging has been utilised, both preclinically and clinically, as a tool for assessing inflammation. Psoriasis is a chronic inflammatory skin disease characterised by hyperkeratosis, dermal inflammatory infiltrate and increased angiogenesis. The aim of the present study was to assess the usefulness of thermography in psoriatic lesion regression after topical treatment with bee propolis, recognised as potent antioxidants and anti-inflammatory agents.. We monitored the inflammation process induced by irritants such as n-Hexyl salycilate (HXS) or Di-n-Propyl Disulfide (PPD) by histopatological assessment of the skin, thermographic scanning, total number of inflammatory cells in the peritoneal cavity, differential analysis of cells in the peritoneal cavity, macrophage spreading index, haematological and biochemical parameters, frequencies of micronucleated reticulocytes, lipid peroxidation and glutathione assay in the skin.. Topically applied ethanolic extract of propolis (EEP) with HXS or PPD reduced the lipid peroxidation in the skin and total number of inflammatory cells in the skin and peritoneal cavity, functional activity of macrophages, the number of micronuclei in mouse peripheral blood reticulocytes and enzymatic activity of ALP and AST.. These results demonstrate that topical application of EEP may improve psoriatic-like skin lesions by suppressing functional activity of macrophages and ROS production. Taken together, it is suggested that EEP can safely be utilised in the prevention of psoriasis-related inflammatory changes without causing any toxic effect.

Topics: Animals; Anti-Infective Agents; Antioxidants; Disulfides; Drug Evaluation, Preclinical; Glutathione; Lipid Peroxidation; Macrophages; Male; Mice; Micronucleus Tests; Oxidative Stress; Peritonitis; Propolis; Psoriasis; Salicylates; Thermography

An experimental and theoretical methodology is proposed to calculate the permeability of microcapsules that contain a core of oil-based active ingredient. Theoretical analysis is performed considering the polydispersity of the measurable capsule size, which allows the estimation of the permeability polydispersity via three different methods. The models proposed were applied in order to determine the permeability of melamine-formaldehyde microcapsules with hexyl salicylate as core oil. Release experiments were performed with four different co-solvents (ethanol, propan-1-ol, propan-2-ol and 1,3-butanediol) of different concentration. Permeability values were found to be constant, despite a two order magnitude of difference in the solubility concentrations.

Topics: Capsules; Models, Chemical; Oils; Particle Size; Permeability; Salicylates; Solvents; Triazines