Contrary to Marine Environments, Common Microplastics in Freshwater Systems May Not Emit Dimethyl Sulfide: An Important Infochemical

Abstract

The ingestion of microplastics by marine species has been at least partially attributed to plastics emitting a dimethyl sulfide signature when exposed to marine conditions. Dimethyl sulfide, a member of the volatile organic sulfur compounds group, is an infochemical that many species rely on to locate and identify prey while foraging. Microplastic ingestion is also observed in freshwater systems; however, this study shows that the same dimethyl sulfide signature is not obtained by three common types of plastic (high-density polyethylene, low-density polyethylene, and polystyrene) in freshwater systems, suggesting that there may be an alternate mechanism driving plastic ingestion by freshwater species.