Microplastic contamination in giant tiger prawn and greasyback shrimp from Malaysian waters

Abstract

Microplastics (MPs) are ubiquitous contaminants in the marine environment. The potential pathway through the food web to humans is a general public concern. Commonly consumed marine organisms have never been studied for the presence of MPs as an entry route into the food chain. This study selected Penaeus monodon (tiger prawn) and Metapenaeus ensis (greasyback shrimp) because of their commercial importance, high consumption rates, and consistent availability in Miri, Sarawak, Malaysia. Samples were collected from major fish markets supplied by both coastal fisheries and aquaculture farms. The gastrointestinal tracts of both species were analyzed under a microscope, and Attenuated Total Reflectance Fourier-Transform Infrared (ATR–FTIR) spectroscopy was performed on suspected MPs based on their physical characteristics. All samples contained plastic: 280 ± 91 pieces/kg wet weight for P. monodon and 457 ± 171 pieces/kg for M. ensis. Fibers were the dominant shape of the MPs observed, followed by fragments and pellets; black was also the dominant color. Most of the particles determined by size were within 500 to 1000 μm in dimension. Polyester and polystyrene were the two major types of polymers by the FTIR analysis. This calls for urgent reinforcement in food safety measures accompanied by environmental policy interventions directed towards microplastic contamination in seafood that encapsulates potential health risk avenues to consumers as well as broader ecological impacts.