Are sunscreen UV filters polluting our beaches? A case study from consumer habits to water analysis on the French Mediterranan Coast Coauthors

Abstract

Sunscreens are of emerging concern regarding environmental health because, during bathing activity, the UV filters incorporated in high concentration can be released from the consumer’s skin to the coastal ecosystem. In order to assess this release from beachgoers into seawater, a field campaign was carried out during the summer of 2017 at three beaches in Marseille, along the French Mediterranean coast. A social survey analyzed beachgoer attendance, the quantities and types of suncare products used and the bathing frequencies, while the bathing water was analyzed spatially and temporally so as to quantify both mineral and organic UV filters directly released and recovered. During the peak recreational time at the three beaches, both mineral and organic UV filters were detected in higher concentrations in the bathing area than offshore. Moreover, higher concentrations were recovered in the water top surface layer than in the water column, ranging at 10-1000 μg/L for mineral and 10-500 ng/L for organic UV filters. More than 75% of the 471 interviewees reported bathing every time they go to the beach, with 68% using a suncare product 2.6 times on average. We could estimate that an average mass of 52 kg/day or 1.4 t/month of suncare products are possibly released into bathing water for a beach attended by 3,000 people daily. Our study revealed two distinct scenarios for the mineral and organic filters. While up to 45% of the mineral filters used by beachgoers were recovered in the seawater, the organic filters were minimally recovered, most likely due to internalization through the skin barrier or partial photodegradation.