Zinc Pyrithione

Zinc pyrithione is a common anti-dandruff active, and it sits at depends because its main market judged it a reproductive risk while another still permits it. In 2018 the European Chemicals Agency classified it as presumed toxic to reproduction, category 1B, on the basis of animal developmental studies, and the EU used that classification to prohibit it in cosmetics from March 2022. Europe's consumer-safety committee had separately judged a rinse-off shampoo at up to one percent safe for the user, so the prohibition was not a finding that your shampoo harmed you; it applied a rule that removes reproduction-classified substances from cosmetics once a suitable alternative exists, and here one does, since brands reformulated around ingredients like piroctone olamine. The United States reached the other conclusion and still allows it, which is the regulator split behind this rating. The developmental studies that anchor the classification are old and held inside the regulators' files rather than openly published, so the strongest evidence a reader can check is the classification and the prohibition themselves. What that adds up to is a product-and-market call: a US rinse-off at up to one percent is within the exposure Europe's own reviewers called safe, while the cautious choice, and the one to make in pregnancy, is a shampoo built on one of the gentler alternatives.