The Study
Systemic availability of lipophilic organic UV filters through dermal sunscreen exposure.
This study found that chemicals from sunscreen can get into people's blood after they use it, like a tracer showing where the chemicals go. But it didn't check if those chemicals make people sick or not—so we can't say sunscreen is harmful, just that the chemicals get inside you.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
Scientists tested if sunscreen chemicals soak into the body when people use it normally.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 525 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — these levels are high enough to trigger FDA requirements for long-term safety studies, and the chemicals stay in the body for days.
- 2After one day of sunscreen use, octocrylene reached 25 μg/L in blood, avobenzone 11 μg/L, and its metabolite CDAA reached 1352 μg/L in blood and 5207 μg/g creatinine in urine.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Environment international
Year
2019
Authors
J. Hiller, K. Klotz, Sebastian Meyer, W. Uter, K. Hof, A. Greiner, T. Göen, H. Drexler
Related Content
Claims (4)
Chemical sunscreen ingredients such as oxybenzone and octocrylene enter the bloodstream at levels higher than the FDA requires for mandatory long-term safety testing.
After using sunscreen containing octocrylene, the body converts it into a compound called CDAA, which builds up to much higher levels in the blood and urine than the original chemical.
When people apply sunscreen containing octocrylene and avobenzone to their skin, these chemicals and one of their breakdown products enter the bloodstream at measurable levels within one day of normal use.
Octocrylene and its metabolite CDAA remain in the body for 1.5 to 2 days after application, leading to buildup with daily sunscreen use, while more water-soluble UV filters are cleared more quickly and do not accumulate.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.