According to the Skin Cancer Foundation, one in five Americans will develop skin cancer by the age of 70 and more than two people die of skin cancer every hour. Sunscreen is imperative to preventing cancer and early aging, but should we be worried about potentially unsafe levels of chemicals entering our body? 

David Andrews, a senior scientist for the Environmental Working Group (EWG), told CNN, “What is most alarming about these findings is that chemicals are absorbing into the body in significant amounts and the ingredients have not been fully tested for safety." 

A randomized clinical trial published in the journal JAMA in May 2019 indicated that chemicals avobenzone, oxybenzone, octocrylene and ecamsule are absorbed through the skin. The more recent study, published Jan. 21, 2020, added three more chemicals to the list: homosalate, ooctisalate and octinoxate. These chemicals are concerning because they have not been officially regarded as safe and effective. 

Rob Chilcott, a professor of toxicology at the University of Hertfordshire in the UK, explained to CNN that these chemicals don’t necessarily mean they are “unsafe to use,” but that “appropriate safety tests need to be performed by manufacturers.”

Let’s break these chemicals down and dive deeper into how our body absorbs them when we apply sunscreen. 

Oxybenzone - Oxybenzone affects hormone activity and lowers testosterone levels. It also contributes to short pregnancies and birth weights in newborns. A 2019 study also found that oxybenzone may be in breast milk, urine and blood plasma due to its high absorption rate. The EWG reported in 2018 that oxybenzone is in two-thirds of all sunscreens sold in the U.S.

Unlike the U.S., the EU has replaced oxybenzone with more protective substances, but those ingredients haven’t been approved by the FDA and are awaiting testing. Side effects of oxybenzone include rashes, acne and skin irritation, though these are rare.

Homosalate - Similiar to oxybenzone, homosalate affects hormone activity once absorbed. Skin rashes, acne and skin irritation are rare side effects of the toxic chemical. Estrogen, androgen and progesterone have all been found to be disrupted when the body is exposed to homosalate

Octinoxate - Octinoxate is one of the most common ingredients in sunscreen, and it disrupts estrogen in humans as well as wildlife. In moderate to high dosages, the chemical can also contribute to low sperm counts in men and can change the size of a uterus. Almost every mainstream company uses octinoxate in their products. 

Octocrylene - Octocrylene has high rates of skin allergy, and like oxybenzone and octinoxate, it is a UV filter that absorbs into the skin. The most alarming issue of octocrylene is that it can contribute to developmental abnormalities. Moreover, the chemical can increase the risk of skin cancer and premature aging

Avobenzone - Other chemicals like octocrylene, homosalate, and octisalate, when combined with octocrylene, can cause skin reactions like irritation, rashes and acne. This main ingredient has shown toxic reactions to chlorine as well. A study published in Chemosphere found the reaction with chlorine can dangerously affect the liver, kidney and nervous system. 

Ecamsule - In Jan. 2015, the FDA announced that ecamsule wasn’t effective or safe. The ingredient has been on the market with L’Oreal in the U.S. since 2006 after the company was able to gain approval. In comparison to avobenzone, ecamsule doesn’t degrade as quickly when exposed to the sun and has more stability. No known long-term side effects of ecamsule have been documented, but it can cause rare short-term effects such as dermatitis, dry skin, acne, itching and redness. 

Although the list of ingredients may be concerning, sunscreen is still highly recommended by the FDA to prevent skin cancer.

The EWG recommends a mineral-based sunscreen that has titanium dioxide and zinc oxide. Hawaii has banned sunscreens that contain oxybenzone and octinoxate because of its negative effects on marine ecosystems, according to the Star Advertiser.

The American Academy of Dermatology does not classify these ingredients as dangerous and suggests applying one ounce of sunscreen every two hours to the back, neck, face, ears, legs and any other part of the body that is exposed to the sun. 

If you're wearing sunscreen and are worried about these ingredients, it may be worth looking into natural alternatives or non-chemical sunscreens. Look for sunscreens that are 50% or lower (a higher SPF doesn’t really mean much) and have a short ingredient list rather than a long list of words you can’t pronounce. Always read the labels, and always do your research.