Safety requirements in cosmetic formulation strategy

Safety is not added to cosmetics by controls, but should be built-up since the starting phases of project development. Various key elements must be taken into account. In the formulation phase, an accurate selection of the ingredients should be performed in order to obtain functionality and compliance, but also stability and innocuity. Main ingredients and actives shall be well known substances, but ingredients such as vegetal extract and hydrolisates are generally only partially known. In all cases purity levels are relevant. Preservants are the only substances added to cosmetics having high and well known levels of toxicity. Since they are necessary to counteract microbiological contamination, the ´safety´ actions can be: complete elimination (few cases), alternative systems (enzymes), proper blends, adequate packaging. In cosmetics like detergents the use of surfactant blends, the addition of anti-irritants, the reduction of interaction with the skin may help to get adeguate respect of skin equilibrium. In sun products the possible safety actions are the reduction of transdermal delivery, the use of blends of organic and mineral filters or increasing the fotostability of sunscreens. Test categories available in the field of the cosmetic innocuity are: in-vitro, ex-vivo, in-vivo and in-use trials.