Most of us know that chemical-based sunscreens aren’t great for our health or the environment, but the research into exactly which chemicals are harmful and why is still ongoing. While reports have shown that common sunscreen chemicals such as oxybenzone (an endocrine disruptor) and vitamin A (may actually increase your skin cancer risk) may be harmful, avobenzone has largely snuck by unscathed until now.
Avobenzone is widely used across the world in sunscreen and cosmetics, valued for its ability to absorb ultraviolet light in a wide range of wave lengths. It was approved by the FDA in 1988 and is considered safe in itself.
But in a recent report published in the journal Chemosphere, scientists from the Faculty of Chemistry at Lomonosov Moscow State University demonstrated that avobenzone breaks down into harmful compounds when it interacts with chlorinated water and ultraviolet radiation. Some of these compounds are considered highly toxic — exactly how they affect human and environmental health remains to be quantified.
Chemist Albert Lebedev, one of the project authors, says, “On the basis of the experiments, one could make a conclusion that a generally safe compound transforms in the water and forms more dangerous products.”
The scientists continue to study the transformation of avobenzone under a variety of conditions, including the use of bromine in place of chlorine in pools. Spoiler alert — the number of breakdown compounds is even higher. And if the water contains copper salts to create that lovely blue color, your sunscreen could break down into compounds known to provoke liver, kidney, and nervous system disorders.
So what sunscreen should you use? Stick to the mineral-based sunscreens that use either zinc oxide or titanium dioxide as their active ingredient. These are especially good if you plan to swim with any sort of wildlife, as even biodegradeable sunscreen can be harmful if ingested before it has the chance to breakdown.
And better yet? Cover up instead. There is plenty of great gear out there that will protect your skin while keeping you cool.