Human Skin Patch Test

Cosmetic products come into direct contact with human surfaces during use and may cause adverse reactions including skin reactions if the product is faulty. CD Formulation can develop patch tests for clients as safety assessment tests to detect the potential for adverse skin reactions to ensure the safety of cosmetic use.

Background

Cosmetics come into direct contact with human surfaces during use, and if there are problems with the product, it may cause serious consequences including skin reactions. Therefore, several tests must be performed before a cosmetic product is marketed to ensure its safety when used. One common cosmetic safety test is the patch test, which detects the potential for the subject to cause adverse skin reactions in humans.

Our Services

CD Formulation offers the most common types of skin patch tests, including closed patch tests, repetitive open patch tests, and repetitive damage patch tests.

Test Selection

• In general, closed skin patch tests are commonly used for cosmetic products.
• Under special circumstances, such as spot cosmetics and powder sunscreen cosmetics, in the human skin patch test irritation results or the results are difficult to determine, the skin should be added to the repetitive open application test. Skin repetitive open type test also applies to drenching products, hair dyes, hair removal and other products.

Experimental Precautions

1. Select qualified volunteers as test subjects.
2. Apply standardized patch test materials for human skin patch test.
3. According to the different types of cosmetics, choose the original or diluted cosmetic products for patch test.
4. When the human skin patch test for spot removal cosmetics and powdered sunscreen cosmetics shows irritation results or the results are difficult to judge, the skin repetitive open application test should be added.

Experimental Steps

Select a qualified patch test device with an area of no more than 50 mm² and a depth of about 1 mm. Put the test substance into the small chamber of the spot test device with the dosage of about 0.02 g-0.025 g (solid or semi-solid) or 0.02 mL-0.025 mL (liquid). When the test substance is the original cosmetic product, the control hole is a blank control, and when the test substance is a diluted cosmetic product, the diluent of the cosmetic product is used in the control hole. The test specimen was applied to the curved side of the forearm with hypoallergenic tape, and the test specimen was applied to the skin with gentle pressure with the palm of the hand for 24 h. The skin reaction was observed after the removal of the test specimen and the results were recorded.

Our Advantages

• Innovative solutions with various types of services

CD Formulation helps provide one-stop innovative solutions for cosmetics, including but not limited to: physicochemical testing, microbiological testing, toxicological testing, safety assessment, and cosmetic efficacy testing/claims support.

• Wide range of services, rich real-world cases

CD Formulation's cosmetic service capabilities span the globe, and we have established in-depth partnerships with many industry benchmark companies to provide scientific validation services in a range of processes including product development.

If you have a requirement about our services, please contact us by phone or email, our colleagues will reply to you within three working days.