Why sunscreens without oxybenzone could be safer
Posted On Apr 15, 2019
With every sculptured sandcastle and yellow polka dot bikini, it has been drummed into our heads that sunscreen is the non-negotiable part of our fun in the sun. Who could forget the famous Coppertone girl with her cheeky dog and tagline “Tan, don’t burn with Coppertone”? Through the years, sunscreen has morphed from a thick creamy paste to lighter creams, oils, and sprays with marketing claims such as “long lasting,” “water resistant,” and “fast absorbing,” reaching impressive new heights. But do all these sunscreens deliver what they say and are they regulated by the Food and Drug Administration (FDA)? It depends on who you ask. The FDA does not routinely test sunscreens; it requires the manufacturers to test their products. In most cases, the companies are not required to submit their results, just keep them on hand in case the FDA asks to see them. Then there is that May 17, 2016 Consumer Report, where it was discovered that a full 43% of more than 60 lotions, sprays, and sticks with SPF claims of 30 or higher – 30 being the minimum level recommended by the American Academy of Dermatology, failed to meet the SPF claim. Which begs the question – are all sunscreens equal in the land of efficacy, safety, labeling and formulations? What about sunscreens without oxybenzone?
Even the consumer is somewhat still confused. In a 2016 American Academy of Dermatology survey, only 32% of respondents knew that an SPF 30 sunscreen does not provide double the protection of an SPF 15 sunscreen, and only 45% were aware that a higher SPF sunscreen did not mean you could stay out in the sun longer. Sunscreens are commonly rated and labeled with a sun protection factor (SPF) that measures the fraction of sunburn-producing UV rays reaching the skin. “If the SPF value is accurate – most often it is not – there is a difference in the UVB protection afforded between a 10, 15, 30 and 50 SPF,” says Denis K. Dudley MD, a Canadian OB-GYN and endocrinologist who is now retired from practicing Maternal Fetal Medicine and Reproductive Endocrinology at the University of Ottawa in Canada. “SPF 10 means that 90% of the UVB band hitting the sunscreen film is prevented from hitting the skin – SPF 15 would absorb 93.4%, SPF 30 would absorb 96.7%, and SPF 50 would absorb 98%. The difference between 30 and 50 is only about 1.3%, arguably insignificant. No one, even dark skinned people, should wear a 10 or 15.” He adds that SPF 25 – 30 is good for most people for everyday use.
There have also been some consumers who attest that they followed the instructions of their sunscreen label to the letter and still came home looking “red.” Dr. Dudley attributes that to various factors. “The solar lamp used in SPF testing in a lab has a cut-off at 400nm where the UV band ends, which is kind of stupid since sunlight continues through visible light and through infra-red and beyond,” he says. “There are studies that show leading brands at SPF 60 -100 if retested in sunlight where it matters, have SPF values usually less than 30% of the label.” Another reason could be that consumers do not always apply the right amount of sunscreen. An average 170 lb x 5’9” male in a swimsuit needs about 1 oz (a shot glass) to cover properly. “Remember that the SPF test in the lab is done with a mandated application of 2mg/cm2 – most consumers apply lower amounts – average 1mg/cm2, which can also be a factor in use effectiveness. The best approach is to always apply sunscreen 30 to 60 minutes before you go out into the sun,” says Dr. Dudley. The American Academy of Dermatology goes further and advises consumers to take the following steps to protect themselves from the sun:
*Broad-spectrum protection means a sunscreen protects the skin from ultraviolet A (UVA) and ultraviolet B (UVB) rays, both of which can cause skin cancer, including basal cell carcinoma, squamous cell carcinoma, and melanoma, the deadliest form of skin cancer. UVB rays cause sunburn; UVA rays penetrate deeper, causing premature aging. Both rays damage the immune system. The amount of protection a sunscreen provides against UVB rays is indicated through its SPF (Sun Protection Factor) number, but until now, the FDA has not required a consistent standard for measuring a sunscreen’s UVA protection.
Our curiosity was further peaked when talking to Dr. Dudley about certain active ingredients found in some sunscreens. In 1991, he found a soluble UV filter called benzophenone (found in some sunscreens as oxybenzone) in fetal blood drawn for fetal assessment at 32-36 weeks gestation. That discovery called for further investigation so he promptly asked his wife, dermatologist Sharyn Laughlin, if she was aware that some of these UV filters had found their way into a fetus. She was surprised. “Many MD’s, caregivers, and most patients are still unaware that oxybenzone (benzophenone), avobenzone, homsalate, octisalate, octocrylene, regular octinoxate, 4-methyl benzildene camphor, and others attain blood and tissue levels,” he said. “The CDC (Center for Disease Control) in the USA reported that 96.8% of Americans had benzophenone (oxybenzone) in their urine (Calafat 2008) from their pervasive use of sunscreens and cosmetics. Consumers deserve to know that soluble UV filters cross the placenta and reach a developing fetus. The alternative is to use an insoluble particle based sunscreen with UV filters like zinc oxide, titanium dioxide, encapsulated octinoxate, bemotrizinol, and biscotrizole to name a few. They never enter through intact skin, have no adverse effects on humans or the environment, and arguably give better broad spectrum protection.”
Two years ago, the Environmental Working Group (EWG) released its Hall of Shame 2015 sunscreen guide, which reviewed more than 1,700 SPF products like sunscreens, moisturizers, and lip balms. The researchers discovered that 80% of the products offered “inferior sun protection or contain worrisome ingredients like oxybenzone and vitamin A.” The EWG referenced two studies (Rodriguez 2006, Krause 2012) claiming that “oxybenzone can cause allergic skin reactions and may disrupt hormones.” This was their full report: http://www.ewg.org/sunscreen/report/the-trouble-with-sunscreen-chemicals/. Is it better to choose sunscreens without oxybenzone? In a 2010 USNEWS article responding to the EWG report, Dr. Henry W. Lim, Chairman of Dermatology at Henry Ford Hospital was quoted as saying “don’t worry so much about the chemicals… these claims are based on studies with mice… other research found no significant changes in blood hormone levels in human volunteers who were told to apply sunscreens containing oxybenzone every day for two weeks.”
Dr. Dudley agrees with Dr. Lim and others from the dermatology/industry alliance who say that the data from studies in mice are not pertinent to humans. “They are right but for the wrong reason,” he says. “Hormone receptors in humans have different kinetics. An undetectable or infinitesimally small dose of a foreign chemical binding to a human receptor can have more severe effects than a higher level – depends on timing.” Dr. Dudley was particularly concerned for pregnant woman and small children when it came to soluble filters such as oxybenzone and avobenzone found in some sunscreens. “Mothers with high levels of oxybenzone in their bodies were more likely to give birth to underweight or small for gestation age baby girls (Wolff 2008),” he added. Definitive studies on fetus, however, can never be done. No ethics board would approve it. “Such a study would also be impractical,” said Dr. Dudley. “You would have to take say a 1000 pregnant women (if you could get their consent) and have them apply sunscreen all through pregnancy, then continue the exposure in their offspring until after puberty, then follow these exposed kids into their forties and fifties to see if they develop infertility, uterine fibroids, uterine or prostate cancer, breast cancer, and the diverse other diseases associated with hormone disruption. The analysis would be impossible as you would have to follow the cohort and rule out other confounding variables like exposure to pesticides, phthalates, and other hormone disruptors.” He also added that there is already enough animal and human data available for a prudent physician or parent to err on the side of caution.
So what percentage of applied dose of a soluble filter would be absorbed into the blood within an hour? “About 5 – 15%,” says Dr. Dudley. “Whatever the amount is, consumers are told to re-apply every 2-3 hours, at the beach and when outdoors, or after perspiring and toweling. Soluble filters wash off more easily and as they are absorbed through the skin, they must be replaced on the surface to have any protective effect. In my opinion, just one day of application every 2 – 3 hours could be harmful to an unborn fetus or a young child.” For the entire family, Dr. Dudley suggests using zinc oxide that is greater than 20% or zinc oxide 15% with 7.5% titanium dioxide or encapsulated octinoxate (E-OMC). These formulations will have no adverse effects on humans or the environment. He is encouraged that Hawaii has just tabled legislation for a complete ban on sunscreens containing benzophenone. He is also not a fan of spray on sunscreens. “It is more difficult to aerosolize particle sunscreens and even the soluble filters require the addition of other noxious agents for this type of delivery,” he said. “Another more compelling reason not to spray is inhalation into the lungs. Even titanium dioxide, a safe particle type filter when applied to intact skin, can cause several adverse effects if inhaled into the lungs.”