Will warmer summers increase the impact of UV filters on marine bivalves?

Marine organisms are constantly exposed to multiple stressors including pollutants released into the environment, such as personal care products (PCPs), and climate change-derived factors, namely warming, which are aggravated by anthropogenic drivers and pose increasing pressure on coastal ecosystems. Avobenzone (AVO) is one of the most used ultraviolet (UV) filters in PCPs which have been increasingly used and, thereby, identified in aquatic environ-ments. However, data regarding the influence of warming on the impacts caused by AVO in bivalves is lacking. Mussels are considered good bioindicators thus being often employed in ecotoxicology studies. Hence, the present study aimed to evaluate the toxic effects of an environmentally relevant concentration of AVO (0.5 mu g/L) and warming (21 degrees C), act-ing alone or in combination, on sperm and adults of the Mediterranean mussel species Mytilus galloprovincialis, through in vitro and in vivo tests, respectively. AVO and warming effects were evaluated by assessing oxidative status, viability, genotoxicity, motility, and kinetics in sperm, together with the quantification of energy content, metabolic capacity, biological defence mechanisms, cellular damage, and neurotoxicity in adults. AVO induced genotoxicity and increased respiration rate in sperm while enhancing the biotransformation enzymes' activity in adults. Exposure to warming led to an increase in respiration rate, ROS overproduction, cellular damage, and viability decrease in sperm whereas met-abolic capacity increased in adults. AVO combined with warming caused oxidative stress, cellular damage, genotoxic-ity, and decreased motility in sperm, while only antioxidant enzymes' activity was enhanced in adults. Overall, the present study demonstrated that when acting in combination the effects of both stressors were more prominent. Fur-thermore, considering the multiple-stressor scenario tested, major toxic effects occurred in male gametes in compari-son to adults.

Automated summary

Marine organisms are exposed to multiple stressors including pollutants and climate change factors, which pose increasing pressure on coastal ecosystems. The UV filter avobenzone is widely used in personal care products and has been detected in aquatic environments. However, little is known about the influence of warming on the effects of avobenzone in bivalves.