Contact allergies of the skin affect approximately 20% of people in the western world. Certain cosmetic ingredients are allergens, especially dyes and perfumes. To test them a new method is being tried out that does not require animal testing.
In 2009 the European Union banned cosmetics manufacturers from testing their products on animals and also from importing any ingredients tested using this traditional approach (the USA has no such law). Since then scientists have been seeking alternative solutions. Researchers at the University of Gothenburg are developing a method based on cultured skin cells, which are exposed to the allergenic substance for 24 hours and then photographed. The number of affected cells provides a measure of the allergenic potential of each substance.