The US Food and Drug Administration (FDA) tested 6 active ingredients that are in commercial sunscreen, sprays AND lotions, on 48 participants and found that they remain in your bloodstream for at least 7 days. Samples of blood were taken during the study to see the chemicals' effects.
One of the chemicals from the sunscreen measured 360 times higher than the threshold allowed by the FDA.
The chemicals tested were octocrylene, homosalate, octisalate, avobenzone, octinoxate, and oxybenzone. Each chemical was found in the participant's blood stream after 7 days... homosalate and oxybenzone were still detected after 21 days.
Both the FDA and American Academy of Dermatology confirm that the chemicals are indeed safe to use. However, there are reports that dispute that some of these chemicals may cause kidney or liver failure, and potential DNA damage.
This just means that more studies should be conducted on these chemicals in order to make a final determination on their use.
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