Supplementary material from "Microplastic leachates impair behavioural vigilance and predator avoidance in a temperate intertidal gastropod"

Microplastics are a ubiquitous source of contaminations in marine ecosystems, and have major implications for marine life. Much effort has been devoted to assess various effects of microplastics on marine life. No evidence exists, however, on the effects of microplastic leachates on chemically-mediated predator–prey interactions and the ability of a prey to detect and avoid its predator. This study shows that microplastic leachates have direct biological effects by disturbing the behavioural response of the intertidal gastropod Littorina littorea to the presence of Carcinus maenas chemical cues, hence increasing their vulnerability to predation. Leachates from virgin and beached pellets respectively impaired and inhibited L. littorea vigilance and antipredator behaviours. These results suggest that the biological effects from microplastic leachates may have major implications for marine ecosystems on taxa that rely on chemosensory cues to escape predation.