What is a Human Repeated Insult Patch Test?
The Human Repeated Insult Patch Test is a six week study designed to identify the potential risks of substances in the tested cosmetic products that can cause irritation or sensitisation on the skin after repeated exposure. The test is conducted on individual volunteers who represent the target groups of customers. The numbers of subjects can be 50, 100, 200, or even more. However, 100 subjects is a recommended number for testing.
The patch is applied to the back of the subjects, and it is allowed to be in direct contact with skin for 24 hours. Then, the patches are removed. One day (24 hours) after the patch is removed, the subjects need to return for evaluation and have the patches planted again. The subjects will be repatched up to 9 times over a three week period. Then, the subjects rest approximately for 14 days. They then come back to have their lower back get patched again.
The whole procedure will be supervised and evaluated by highly trained dermatologist. The evaluation and assessment during the procedure will be recorded. After the end of the study, the findings of the study will be presented to clients in a comprehensible report.