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.