Application of a 4-h human patch test method for comparative and investigative assessment of skin irritation

• Published in: Contact dermatitis Vol. 38; no. 4; pp. 194 - 202
• Main Authors: Robinson, Michael K., Perkins, Mary A., Basketter, David A.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.04.1998; Blackwell
• Subjects: 1-decanol; acetic acid; Acetic Acid - adverse effects; Allergic diseases; Asian Continental Ancestry Group; Biological and medical sciences; chemicals; Dermatitis, Allergic Contact - etiology; European Continental Ancestry Group; Fatty Alcohols - adverse effects; human; Humans; Immunopathology; irritancy; irritant contact dermatitis; Irritants - adverse effects; Medical sciences; neurosensitivity; patch testing; Patch Tests - methods; racial; Skin allergic diseases. Stinging insect allergies; sodium dodecyl sulfate; Sodium Dodecyl Sulfate - adverse effects; sodium hydroxide; Sodium Hydroxide - adverse effects; Time Factors; Human; Skin disease; Investigation method; Chemical compound; Multicenter study; Interindividual comparison; Race; Irritant compound; Patch; Skin test
• ISSN: 0105-1873; 1600-0536
• DOI: 10.1111/j.1600-0536.1998.tb05706.x

A human 4‐h patch test has recently been developed for testing the irritation hazard potential of chemicals. The original method was developed for comparative irritation assessments relative to benchmark irritants using simple statistical tests. In this context, the method has been shown to be robust in intra laboratory testing over time. Recent inter laboratory testing has also established the consistency of the method in assessment of the relative irritation potential of selected chemicals. These data help to position the method as a suitable replacement for animal test methods in assessment of skin irritation hazard. In addition, the method has great utility for investigating different parameters of clinical skin irritation. Using kinetic response patterns and curve fitting analysis, we have compared the relative irritation potential of chemicals in greater detail, using as a basis the time required for test subjects to respond as well as the incidence of positive responses. Also, using the response to 20% sodium dodecyl sulfate (SDS) as a benchmark, we've been able to examine the intersubject variation in clinical skin irritation responses. In general, subjects most reactive to 20% SDS, in terms of the exposure time required to produce a positive response, were relatively more sensitive to a 2nd irritant chemical as well. However, this was not an absolute correlation in that some test subjects showed divergent patterns of response. The method was also used to compare directly the relative skin reactivity of different populations, based on race (Caucasian versus Asian) or on neurosensory skin sensitivity. Our results using this acute exposure test method indicate little difference in visually assessed skin irritation among these diverse human subpopulations.