EU SCCS Identifies Safety Risks in Prostaglandin Analogues, Basic Blue 99, Basic Brown 16, Thiomersal, and Phenylmercuric Salts

On February 10, 2026, the EU Scientific Committee on Consumer Safety (SCCS) released four final opinions concerning prostaglandin analogues, Basic Blue 99, Basic Brown 16, as well as Thiomersal and Phenylmercuric salts. In these opinions, SCCS reaffirmed its conclusions from the preliminary assessments, concluding that these substances cannot be considered safe for use in the relevant cosmetic product categories.^1-4

Opinion on Prostaglandin Analogues

Despite their use in eyelash growth cosmetics, prostaglandin analogues (PGAs) are not currently restricted under the Regulation (EC) No 1223/2009 (the Cosmetics Regulation). In 2021, SCCS evaluated prostaglandins and two analogues—Dechloro Dihydroxy Difluoro Ethylcloprostenolamide (DDDE) and Isopropyl Cloprostenate (IPCP)—raising concerns about their use near the eyes. Additional data for DDDE, IPCP, and a third PGA, Methylamido-Dihydro-Noralfaprostal (MDN), were submitted by January 2024, prompting the European Commission to mandate an updated safety review.

After reviewing all submitted evidence, SCCS determines that DDDE, IPCP, and MDN are unsafe for use in cosmetics intended for eyelash and eyebrow growth, due to their strong pharmacological activity and insufficient data to exclude reproductive or developmental toxicity. SCCS further notes that, although the three PGAs show no genotoxic potential, non-genotoxic carcinogenicity cannot be ruled out in the absence of relevant studies.