4 - Plastic impact on marine benthic organisms and food webs

Abstract

Huge amounts of plastic debris, both macro- and microscopic sizes, float in marine environment and, currently, plastic contamination is widely assumed as an emerging threat to marine ecosystems. To better elucidate its implications on marine habitats, marine food webs, and human health, there is an urgent need to study and understand its distribution, behavior, and the way it interacts with biota. In addition, knowledge about the drivers affecting the bioavailability of plastics to organisms, as well as their potential toxicological and ecological effects, is still limited. While several field studies showed that Mediterranean Sea is strongly affected by plastic contaminants and resident organisms could ingest and interact with them on a daily basis, less information available regarding toxicity in wild organisms. Furthermore, laboratory trials have shown that microplastics can cause mild but adverse effects due to physical and chemical impacts (i.e., physical disturbance and release of additives and/or chemicals adsorbed from the environment). Despite the concerns raised by this evidence, the effects of microplastic ingestion in natural populations and the impacts on food webs are far from being completely understood.