Adding insult to injury: Effects of chronic oxybenzone exposure and elevated temperature on two reef-building corals

• Published in: The Science of the total environment Vol. 733; p. 139030
• Main Authors: Wijgerde, Tim, van Ballegooijen, Mike, Nijland, Reindert, van der Loos, Luna, Kwadijk, Christiaan, Osinga, Ronald, Murk, Albertinka, Slijkerman, Diana
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.09.2020
• Subjects: Acropora tenuis; Benzophenone-3; Climate change; Microbiome; Oxybenzone; PSII yield; Stylophora pistillata; Climate change; Benzophenone-3; PSII yield; Stylophora pistillata; Oxybenzone; Acropora tenuis; Microbiome
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2020.139030

Coral bleaching due to global warming currently is the largest threat to coral reefs, which may be exacerbated by altered water quality. Elevated levels of the UV filter oxybenzone in coastal waters as a result of sunscreen use have recently been demonstrated. We studied the effect of chronic oxybenzone exposure and elevated water temperature on coral health. Microcolonies of Stylophora pistillata and Acropora tenuis were cultured in 20 flow-through aquaria, of which 10 were exposed to oxybenzone at a field-relevant concentration of ~0.06 μg L−1 at 26 °C. After two weeks, half of the corals experienced a heat wave culminating at 33 °C. All S. pistillata colonies survived the heat wave, although heat reduced growth and zooxanthellae density, irrespective of oxybenzone. Acropora tenuis survival decreased to 0% at 32 °C, and oxybenzone accelerated mortality. Oxybenzone and heat significantly impacted photosynthetic yield in both species, causing a 5% and 22–33% decrease, respectively. In addition, combined oxybenzone and temperature stress altered the abundance of five bacterial families in the microbiome of S. pistillata. Our results suggest that oxybenzone adds insult to injury by further weakening corals in the face of global warming. [Display omitted] •Chronic effect study on corals combining oxybenzone and elevated temperature.•Oxybenzone affected PS II of coral photosymbionts and altered coral microbiome.•Temperature effects were stronger than oxybenzone effects.•Sensitivities were species-dependent.•Oxybenzone adds insult to injury by weakening corals in the face of global warming.