Preservatives are used to prevent the growth of microorganisms. They are frequently used in the manufacture of personal hygiene and cosmetic products, medications, and cleaning products. The emergence of undesirable effects induced by preservatives is a relatively recent finding. New preservatives have been introduced over the years to improve safety in use, although this objective has not always been achieved, with the result that we have witnessed successive epidemics caused by newly developed preservatives. In their extensive and exhaustive study, Pastor-Nieto et al.1 analyze preservatives in personal hygiene and cosmetic products, topical medications, and household cleaning products in Spain. The authors observed that exposure to the various preservatives in these products was widespread and that the progressive replacement of parabens by other products such as isothiazolinones can generate greater sources of problems.

Knowledge of preservatives in commonly used products will serve to guide sensitized persons and help them to avoid these substances. It will also play a role in limiting the use of preservatives as much as possible.