Dermal Toxicity Studies

Abstract

The field of dermal toxicity continues to evolve in order to accurately predict dermal (and systemic) responses in humans to topically applied chemicals. Although the testing methods have undergone extensive refinements, idiosyncrasies and unexpected issues during the conduct of these studies are not unusual due to the plethora of new vehicles available for formulating test substances, changing regulatory requirements, and introducting new strain and/or species of laboratory animals as no single species or method seems to suffice for evaluating skin toxicity. The objective of this article is to illustrate some pragmatic issues that should be considered during the conduct as well as interpretation of dermal toxicity studies. Routine procedure-related issues such as hair clipping, tape stripping, and wrapping the animal's torso to prevent oral ingestion can influence the interpretation. Excipients used in dermal toxicity studies may be nontoxic when used alone but complex dermal formulations can result in unexpected irritation and toxicity. In conclusion, interpretation and risk assessment of dermal toxicity studies should be done in a comprehensive manner, taking into account procedure-related impact on study results, unique species susceptibility, limitation of gross visual (naked eye) observation for evidence of toxicity, and normal anatomical variation.

Current challenges facing the assessment of the allergenic capacity of food allergens in animal models

“…Birmingham et al [ 73 ] and Gonipeta et al [ 74 ] sensitized mice to hazelnut and milk whey protein, by transdermal application of the allergen, for 6 consecutive weeks. Although they did not add an adjuvant, they clipped the hair from skin and used mild occlusion for 1 day, which may cause mild inflammatory responses and release DAMPs [ 75 ]. Others [ 54 , 76 ], have used tape stripping methods to promote epicutaneous sensitization to food allergens.…”

Computational Studies Applied to Linalool and Citronellal Derivatives Against Alzheimer's and Parkinson's Disorders: A Review with Experimental Approach

“…The parameters evaluated included: mutagenicity, that is, the ability of the substance to cause mutations in the DNA of the organism in which the bioactive is inserted - by severity [ 177 ]; tumorigenicity, which is the ability of the bioactive to cause tumors [ 178 ]; skin irritability, which corresponds to sensitivity that the compound can cause in the skin or in internal organ tissues such as the esophagus, larynx, stomach, and intestine; and toxicity in the reproductive system, which corresponds to the toxic effects that a substance can have on sexual function, and male and female fertility [ 179 , 180 ]. The results are shown in Table 3 [ 181 , 182 ].…”

Safety of 0.5% hydrogen peroxide mist used in the disinfection gateway for COVID-19

“…In the present study, acute skin irritation and repeated-dose inhalation toxicity was carried out to assess safety of 0.5% of hydrogen peroxide. Skin irritation is considered to be one of the relevant end points of chemicals, and therefore, skin irritation test is critical, if dermal contact is intended (Chandra et al 2015 ). A study on New Zealand rabbits reported that severity of skin irritation increases within the increase in concentration of hydrogen peroxide solution (10% < 35% < 50%).…”