John Found Dip. Chem., C. Chem., MRACI, MAICD
How Dangerous is It?
It soon became apparent with widespread use that benzene had some serious toxicity issues and its use declined over a decade or so. Later researchers began to discover that benzene was a primary carcinogen and was responsible for large outbreaks of leukemia. Like all toxic substances, the dose and frequency of exposure are what determines the risk profile. In the light of this most regulators around the world specify maximum limits in products intended for use on or in humans. The limits are reviewed by independent expert committees to evaluate the risk to consumers and are usually set at several orders of magnitude below known toxicity levels. The pharmaceutical industry is heavily regulated by Government bodies around the world and have the most stringent purity specifications for medicines and devices. The cosmetic and personal care industry is not as regulated and set limits may often be exceeded in certain products.
How does it get into sunscreens?
There are many pathways for benzene’s entry into a suncare product. It may be contained in one or more of the ingredients, for example fragrances and preservatives. It may also be in the plastic used to make the bottle jar or tube the product is contained in. The benzene ends up in the product due to a process called leaching. Leaching occurs when solvents included in the plastic are absorbed by the product it contains.
What levels are considered “safe” ?
There are no levels that can be considered safe for benzene, however, carefully determined maximum levels can be considered low risk for certain product types. For some drugs which contain trace levels of benzene there is a risk/benefit approach whereby the benefit of taking the drug far outweighs the risk due to benzene.
So how are sunscreens monitored in Australia?
Unlike some countries around the world sunscreens are considered medicines in Australia. As part of the regulation process the ingredients used to make sunscreens must comply with tight specifications that don’t allow benzene traces. Fragrances that are known to contain carcinogens like benzene that are used in room deodorants and surface sprays are not allowed to be used in sunscreens.