Hallmarking microplastics of sediments and Chamelea gallina inhabiting Southwestern Black Sea: A hypothetical look at consumption risks

Abstract

The consumer preference of bivalves originating from fishery or aquaculture has gained momentum in response to higher nutrition, quality, and market availability. However, potential toxicity caused by plastics, the pollution icons of the current era, could raise concerns for the sources of essential nutrients provided by bivalves. Thus, we investigated the abundance, spatial distribution, polymer composition, size, and the shapes of the microplastics (MPs) in the sediment and Chamelea gallina from 15 sites at gradual depths (10 and 30 m) along the Southwestern Black Sea coast. The abundance of the MPs ranged from 28 to 684 MP kg-1 in the sediments and the amount of 0.22-2.17 MP individual-1 (or 0.20-2.16 MP g-1 fresh weight soft tissue) in C. gallina. Seven types of polymers were detected by FTIR, and the most abundant type was polyethylene terephthalate (34.2-35.1%), polyethylene (28-31.1%), and polypropylene (18.9-21%). MP sizes were ranged from 73 to 4987 mu m. 47% and 65% of the MPs in the sediments and C. gallina, respectively, were <1000 mu m in size. The most dominant shape of the MPs was found as fibers (56.5% for sediments and 68.9% for C. gallina). The risk data predicted that people are exposed to 304 MPs when consuming a single portion of C. gallina weekly. Hypothetical calculations performed with a chemical additive simulation (bisphenol A) showed that the risk associated with the MP-contaminated C. gallina model is negligible, and the consumption is rather beneficial due to already known positive aspects.