Topical sunscreens are good tools for preventing skin cancer, but it turns out many formulations may be harmful not helpful. Realizing this, the US Food and Drug Administration (FDA) updated regulatory requirements for sunscreen products by reclassifying them as drugs. After testing several common topical sunscreen ingredients, the FDA discovered elevated serum (blood) levels of avobenzone, oxybenzone, ecamsule, and octocrylene. The American Medical Association (May 6, 2019) recently confirmed these findings. It turns out that these chemicals can enter the bloodstream after just one day of use and can remain in the body for at least 24 hours after application.
The February 2019 FDA proposal ensures that sunscreen’s active ingredients are more closely regulated. The FDA study did not find the ingredients would cause health issues, but further studies are pending.
Not all products absorbed thru the skin are dangerous, however, at levels above the acceptable 0.5ng/mL (nanograms per milliliter) there are potential safety concerns. Elevated blood levels of some ingredients could increase the risk for cancer and birth defects, while other chemicals could adversely affect hormone levels in adolescent boys and men. In some cases, pregnancy duration could be shortened resulting in low birth-weight babies.
With over 12,000 sunscreen products on the market, regulation could have the FDA working in over-time. According to a sample analysis of more than 1300 products, the Environmental Working Group reported that over 60% of the sunscreen products do not offer enough sun protection or contain potentially harmful chemicals.
Since the 1970’s there have been many scientific advances in sunscreen contents which has led to greater broad-spectrum protection against UVA and UVB rays. In addition, several products are more potent, and which could lead to greater levels of chemical absorption thru the skin. Others sunscreen products combine insect repellents which add more substances. These combination lotions, if highly absorbed thru the skin, could lead to additional health risks.
The use of sunscreen sprays and powders should be avoided because the aerosolized particles could enter the lungs leading to chronic lung conditions. I do not recommend their use, especially in children.
This information should not deter you from using sunscreens. Recently, I published an article reviewing the necessity of sunscreen product to prevent skin cancer. Reducing numbers of skin cancer cases is most important as it is highly prevalent and the most common cancer in the US with rising numbers of cases due to excess sun exposure. Due to recent concerns, consider looking for products with zinc oxide and titanium dioxide which are not absorbed thru the skin. Don’t forget to wear protective clothing in addition to hats and sunglasses.