Microplastics in Commercial Fishes in the River Ganga and Their Human Health Risk Assessment

This study investigates microplastics (MPs) contamination in four commonly consumed freshwater fish species from the Ganga River, India: Cyprinus carpio or Common carp, Sperta aor, Johnius coitor, and Labeo bata. We analyzed the gastrointestinal tracts (GIT) and dorsal muscles of 62 fish specimens collected in the Varanasi region. MPs were detected in the GIT of approximately two-thirds of the fish, while only 15% of the fish contained MPs in their muscle tissue. The highest concentration of MPs in GIT samples was 19.04 items/g in Johnius coitor, while Common carp had the highest MPs concentration in muscle tissue at 0.60 items/g. Notably, the majority of MPs in both GIT and muscle samples were fibrous, with black and blue being the dominant colors. Raman spectroscopy identified poly(m-phenylene terephthalamide) as the most abundant polymer, comprising ∼35% of all identified MPs. A polymer hazard index assessment indicated that ∼37% of the detected polymers are categorized as hazardous. Although the overall pollution load index was low for all fish species, the presence of dangerous polymers in edible fish tissues highlights a potential pathway for human exposure and a potential threat to public health, necessitating further investigation into the impacts on aquatic ecosystems and consumers.