Microplastics in the Marine Food Chain – Insights from Commercially Consumed Finfish Species in Puducherry, India

Microplastics (MPs), defined as plastic particles smaller than 5 mm, arise from the degradation of larger plastics or direct introduction, and are increasingly pervasive in global marine environments, posing risks to marine species, ecosystems, and potentially human health across all trophic levels. This research examines the frequency, attributes, and ecological consequences of MP pollution in six commercially important marine finfish species (Malabar Trevally, Small-scaled Terapon, Silver Croaker, Yellowstripe Scad, Bigeye Snapper, and Pugnose Ponyfish) gathered from three coastal landing sites in Puducherry, India. A total of 1,597 MPs were enumerated from 120 specimens. Microplastics were identified in all fish species, with average amounts varying from 10.85 ± 0.89 to 14.65 ± 1.16 particles per specimen. Fibres constituted the majority of microplastic shapes (84.1%), followed by pieces, pellets, and films, with black being the most often seen hue. FTIR spectroscopy examination of polymers revealed a dominance of polypropylene (PP), low-density polyethylene (LDPE) and high-density polyethylene (HDPE), and polystyrene (PS), with specific patterns associated with eating behaviours and habitat use. Comparisons with previous regional and global research reveal that feeding ecology, habitat strata, and local anthropogenic stressors influence the spatial and interspecific heterogeneity of MPs ingestion. These data indicate moderate levels of MPs contamination in the Puducherry marine ecosystem, affecting seafood safety and ecosystem health. This study contributes to the growing body of evidence on the prevalence of microplastics in the marine food web. It highlights the need for enhanced management and legislative initiatives to mitigate plastic pollution in coastal areas.