First evidence of microplastics in commercial mussels from Amazonian estuaries

Microplastics (MPs) are widespread pollutants, however there are no data regarding the contamination of Amazonian bivalves. This study is aimed to verify the occurrence of MPs in the commercial mussel Mytella guyanensis harvested from two estuaries: Caeté River and Pirabas River. Mussels from both Caeté (0.15 ± 0.14 MPs/g) and Pirabas (0.20 ± 0.19 MPs/g) had MPs in their soft tissues. The concentration with MPs/g showed no difference between areas. Fibers were the most abundant MP shape, followed by pellets. Caeté had significantly more pellets than Pirabas. The most frequent items found in mussel samples were confirmed through μ-FTIR analysis as MPs: white polystyrene pellets and black and blue polyamide fibers. We confirmed for the first time the occurrence of MPs in bivalves from two estuaries in the Amazon region. The mussels showed expressive contamination, which raises concerns for the risks these pollutants pose to estuarine ecosystems and human health.