Assessment of the Biological Response of the Scleractinian Coral Seriatopora Hystrix to Sunscreen Products

Author(s): Andrezza DPM Canavez, Eloïse Renouf, Marine Mercy, Marcio Lorencini, Carla Abdo Brohem, Desiree C Schuck

Every second, 0.8 litres of sunscreen enters ocean waters, which corresponds to the release of 25.000 tons per year. UV filters may present substantial threats to marine fauna and flora and have an impact similar to that of other contaminants. Coral reefs play a major role in marine biodiversity, and some publications suggest that they are threatened by the release of sunscreen into the environment, which should cause bleaching. The aim of this study was to evaluate the potential impact of sunscreen products on hard corals. Laboratory experiments in which Seriatopora hystrix coral fragments were exposed to 9 sunscreens at concentrations up to 100 mg/L for 96 hours were conducted, and the biological responses of the fragments were assessed. The examined parameters were coral bleaching and polyp retraction. The results obtained revealed that the 9 tested sunscreens had no effects on S. hystrix, with a recorded NOEC (No Observed Effect Concentration) of 100 mg/L for both tested parameters. This concentration is much higher than those of chemicals in the natural environment, which are on the order of µg/L or ng/L. Under the conditions in this experiment, the absence of toxic effects from the tested sunscreens allows us to argue the absence of potential danger on corals.