Health scare of the week

The chemicals in sunscreen don’t just sit on the skin after application—they are quickly absorbed into the bloodstream. In an experiment by the Food and Drug Administration, 24 volunteers applied one of four common brands of sunscreen four times a day for four days on the parts of their body that wouldn’t be covered by a swimsuit. The researchers then tested their blood for levels of four of the products’ active ingredients: avobenzone, oxybenzone, octocrylene, and ecamsule. After the first day, levels of all four chemicals exceeded the toxicology threshold, the level above which the FDA recommends additional research. Three of the ingredients were still in the bloodstream after a week, with levels of oxybenzone—which has been linked to low testosterone levels, hormone changes, and shorter pregnancies—40 times the FDA’s threshold. The chemicals are among a dozen that the agency said needed to be examined by manufacturers before they can be considered “generally safe and effective.” But researchers urge people to keep using sunscreen, which can help prevent skin cancer, while further research is carried out. “Just because [the chemicals] are absorbed,” co-author Theresa Michele tells NBCNews.com., “doesn’t mean they are unsafe.”

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