Coupled exposure to ingredients of cosmetic products: II. Preservatives

Background. The use of cosmetics exposes consumers to mixtures of ingredients, many of which are potential allergens. Many cosmetics contain one or several preservatives, some being important contact allergens. Objective. To examine the pattern of co-exposure to preservatives in different categories of cosmetics. Methods. A survey of products marketed in Germany, conducted in 2006-2009 by the Chemical and Veterinary Investigation Office in Karlsruhe, identified 4680 products categorizable according to Annex I to the Cosmetics Directive with information on the presence of preservatives. The occurrence and co-occurrence of preservatives were analysed and presented in tabular and graphical format. Results. Thirty per cent of all products were not declared to contain any preservatives; for 8%, no INCI labelling was present. For the remainder, the number of preservatives used tended to be higher in leave-on than in rinse-off products. Most often, combinations of (up to all five) parabens were used (39% of all products). Combinations with phenoxyethanol were also frequent. Formaldehyde releasers were found in 8% of products overall. Conclusions. The pattern of co-exposure to preservatives in important categories of cosmetic products illustrates the 'cocktail' of allergens that may facilitate sensitization, although, conversely, the combination of preservatives allows individual use levels to be kept lower, thereby possibly reducing sensitization risk.