Cosmetic product tests : what are they for ? How must laboratories test their cosmetic products ?

There are regulations on cosmetic product testing at European level, in the form of EU Directive 76/768 27/07/1976 . This directive defines cosmetic products as "any substance or preparation intended for placing in contact with the various external parts of the human body (epidermis, hair system, nails, lips and external genital organs) or with the teeth and the mucous membranes of the oral cavity with a view exclusively or principally to cleaning them, perfuming them or protecting them in order to keep them in good condition, change their appearance or correct body odours.".

Even if cosmetic products, contrary to the test for medicines, do not have to prove their effectiveness before being put on the market, they must be tested to prove that they are harmless under normal conditions of use. To this test we must also add abnormal but foreseeable conditions of use (for example, handling by a young child), in which the product must remain harmless. Packaging and labelling play a major role in defining normal conditions of use.

To limit cosmetic product tests, there is a list of authorised, restricted and forbidden product ingredients or components. The application of a cosmetic product can generate three different effects:

• a local, irritating effect (which can provoke an inflammatory reaction) or corrosive reaction (which is a more destructive action), by immediate, protracted or repeated contact with skin or mucuous membranes
• an increased sensitivity, which could develop into an allergic reaction or could make the skin become more sensitive to the sun
• a systemic effect, due to the transit of the product or of one of its components through the entire body

Cosmetic product tests on human volounteers therefore include mainly dermatological examinations but may also include more global examinations to evaluate potential systemic reactions.