Consumers may take in larger amounts of coumarin from cosmetics, too
The natural flavouring, coumarin, can cause liver damage in highly sensitive individuals. However, the effect can be reversed once coumarin intake is halted. This plant ingredient is found in woodruff and sweet clover and there are higher levels in cassia cinnamon, too. Consumers mainly ingest coumarin from food containing high levels of cassia cinnamon. Furthermore, synthetically produced coumarin is added as a fragrance to cosmetics and can reach the body through the skin. The Federal Institute for Risk Assessment (BfR) has evaluated the analytical results of the controlling bodies of the federal states in order to assess the scale on which cosmetics contribute to consumer exposure to coumarin. The result: consumers could already exceed the tolerable daily intake (TDI) of coumarin just by using cosmetics with high coumarin levels. Up to now, it has not been fully elucidated whether coumarin taken in via the skin has a similarly harmful effect on the liver to coumarin ingested from the gastro-intestinal tract. Until this question has been fully answered, BfR assumes on precautionary grounds in its assessment that the hepatotoxic effects are comparable in both cases. "Consumer exposure to coumarin, which also includes cosmetics, should be reduced", says Professor Dr. Dr. Andreas Hensel, BfR President. No coumarin should be used in cosmetic products for infants and toddlers as a precautionary measure. Further analyses of cosmetics are needed as the available data do not yet provide a comprehensive overview of their coumarin levels. Manufacturers are called on to make the necessary data available.
Coumarin can damage the liver of particularly sensitive individuals. In animal experiments high concentrations of the substance have triggered cancer. Based on hepatotoxicity a tolerable daily intake (TDI) of 0.1 milligram coumarin per kilogram bodyweight was derived for coumarin which should not be exceeded in the long term.
Coumarin is not just to be found in food; it is also used in cosmetics. As a synthetically produced fragrance, coumarin gives perfumes, shower gels, lotions and deodorants a tangy scent of lavender or moss. Whereas a maximum of two milligram coumarin per kilogram may be added to foods as a flavouring, there are no maximum limits for coumarin in cosmetics. However, as coumarin - like many other fragrances - can trigger allergies in highly sensitive individuals, too, it must be labelled as an ingredient in cosmetics from specific concentrations upwards. Coumarin easily reaches the human body through the skin. Cosmetics can, therefore, contribute to the total exposure of consumers to coumarin.
Up to now, scarcely any data were available about the scale and amount of coumarin contained in cosmetics. The controlling bodies of the federal states, therefore, examined random samples of cosmetics for coumarin. These were mainly perfumes but also skin gels, body lotions and oils - i.e. products which remain on the skin after application. If one takes the maximum levels of coumarin measured in the perfumes examined as the basis (worst case estimate), then coumarin intake can considerably exceed the TDI. In children the regular use of skin gels, body lotions and oils with high levels of coumarin could exhaust up to 20 percent of the TDI.
The main basis for setting the TDI was dietary coumarin intake. Whether coumarin taken in via the skin has the same effect on the liver as identical amounts ingested from food has not yet been fully elucidated. There are some suggestions that coumarin taken up through the skin could be less hepatotoxic than orally ingested coumarin. Until this question has been fully elucidated scientifically, BfR assumes comparable effects on precautionary grounds.
The Institute recommends reducing overall exposure to coumarin and this also includes cosmetics. No coumarin should be used at all in care products for infants and toddlers. Further analyses of the coumarin levels in cosmetics are necessary as it cannot be ruled out that besides the samples examined, there are other cosmetics with higher coumarin levels on the market.