This 2001 study tested whether Tinosorb M-active and Tinosorb S could act like hormones in the body. Both filters showed no binding to estrogen or androgen receptors, and neither triggered hormone-like responses in animal tests—suggesting they don't have endocrine-disrupting activity.
Researchers used lab tests to see if these sunscreen filters could bind to hormone receptors, then confirmed findings with animal studies. Control chemicals that *should* trigger responses did, validating the test methods.
Funding not disclosed in abstract