Determination of octocrylene, benzophenone-3 and its derivatives in Spanish surface waters by solid-phase extraction/gas chromatography−mass spectrometry

Benzophenones (BPs) are widely known UV filters capable of absorbing various radiation wavelengths and hence useful agents for skin protection. In Europe, sunscreen lotions must contain not more than 6 % w/w benzophenone-3 (BP-3), usually in combination with other filters such as octocrylene that may be degraded into BPs and thus require monitoring. In this work, we developed a method based on continuous solid-phase extraction (SPE) with Oasis HLB as sorbent and gas chromatography-mass spectrometry (CG-MS) for determining octocrylene and ten different benzophenones. The method was validated in terms of recovery (83-112 %), linearity, matrix effects (<20 %), precision (relative standard deviation < 10 %) and limits of detection (20-40 ng/L). Then, it was used to analyse a total of 43 pool, river, reservoir, sea, waste, tap and well water samples. Only two of the samples contained none of the analytes at detectable levels, all others containing some UV filter, at concentrations from 67 to 3.1 10³ ng/L. The widespread presence of sunscreen-derived compounds in various water bodies, but particularly those used for recreation or consumption, raises serious concerns about their potential impact on health, and underscores the need for continuous monitoring and regulatory measures to help mitigate the associated risks.