I have my parenting flaws. For instance, a lack of patriarchal oversight and an overreliance on Velcro sneakers means my children are usually about 8 years old before they can tie their shoes. But none of them have ever been sunburned. We carry sunscreen in our minivan so that we can never forget it and in case we launch an impromptu outdoor adventure. As unpleasant as sunburns are, excess exposure to ultraviolet radiation can also lead to prematurely aging skin and cancer.
However, some reports, most notably one from the Environmental Working Group, warn that the sunscreens we use for protection may actually be doing harm. Most of the worry centers on the chemical oxybenzone. This mouthful of an ingredient serves as an ultraviolet filter which absorbs the sun’s rays so our skin doesn’t have to.
The challenge in determining a chemical’s dangers or lack thereof was addressed by Popular Science. (Incidentally, it doesn’t matter if science is popular, what matters is if it’s right). The article noted that cyanide will cause an exposed person to expire within 10 minutes, while asbestos could take years to unleash its fatal effects. From the story: “The gap between exposure and the emergence of disease is called latency and it’s just one of many issues that make it tough to determine a chemical’s safety.”
Adding to the challenge is that exposure to a certain chemical doesn’t take place in isolation. Popular Science envisioned an asbestos-removing chain smoker who develops lung cancer. Did the disease result from his habit, his employment, both, or neither? His exposure to toxins at his work and in his cigarette made the man’s risk higher, but did not guarantee cancer any more than a regimen of vitamins, minerals, vegetables, and cross training will ensure freedom from the disease. So trying to figure out the roles that exposure plays requires repeated research.
Dosage also matters. In one study, young rats ingested large amounts of oxybenzone and developed large uteruses (all test subjects were female, otherwise this would have been quite a result). This occurence suggested the lab rats experienced hormonal effects, which in humans can increase cancer risk. However, these findings are not without limitations. The dose was extremely high, no people are rats, and humans don’t consume vast quantities of sunscreen, though my 3-year-old son has tried. J.R. Thorpe at bustle.com noted that scientists have determined that persons would need to pile on inches-deep levels of oxybenzone over their entire body for 36 years to have an exposure equivalent to what was forced on the rodents.
Another study on human cells found that oxybenzone can mimic estrogen and block testosterone, especially in breast cells. Buy this result again comes with a caveat. Cellular studies are often a poor indicator of what will happens inside a person. The body may have mechanisms that counteract the goings-on inside a Petri dish.
There are other worries about a second sunscreen ingredient, retinal palmitate. These concerns stem from a study which shows that, when exposed to UV light, the chemical can produce free radicals, which are tied to cancer development. However, the Skin Cancer Foundation points out this study was also done on lab rats, not human skin. Further, it was never published and thus not peer-reviewed or replicated, and antioxidants inherent in people can tame the effects of free radicals.
Other studies have linked regular sunscreen use to melanoma, but this may be a result of inefficient use, specifically not applying the lotion often enough throughout the day.
The American Academy of Dermatology recommends everyone wear a water-resistant, broad-spectrum, SPF 30 minimum sunscreen. This is especially vital for children since early sunburns increase the likelihood of skin cancer later in life. No published studies conclusively show that sunscreen is deleterious to human health. To the contrary, research indicates that wearing sunscreen reduces the risk of risk of skin cancer and prematurely aging skin. There is insufficient research to declare oxybenzone unquestionably safe, but if having such concerns, putting on long-sleeve shirts, full-length pats, and the millinery wear of your choice is better than trying an unproven sunscreen alternative.
I especially discourage eschewing sunscreen for coconut oil, a technique touted by alt-med types. Wellness Mama offers precisely this tip in her post, “How to make natural homemade sunscreen,” an oxymoronic suggestion since if you have to make it, it’s not natural. More importantly, the Mayo Clinic states that coconut oil blocks a negligible 20 percent of UV rays and it has an SPF of 7, less than a quarter of the minimum recommendation. The only way to safely use this product is indoors.