Plastic in seafood: are crustaceans a gateway to microplastic exposure in humans?

Crustaceans, widely consumed and ecologically significant marine organisms, are increasingly affected by microplastic (MP) pollution, one of the most pressing environmental challenges of the 21st century. These benthic and pelagic species, including shrimp, crabs, and lobsters, play essential roles in nutrient cycling, food web dynamics, and global seafood supply. The proliferation of plastic waste has led to widespread MP contamination in marine environments, threatening both ecological stability and human health. This review provides an in-depth overview of MP pollution, its ingestion and accumulation in crustaceans, and the resulting biological and toxicological effects. Data were compiled from leading academic databases, including Scopus, Web of Science, PubMed, ScienceDirect, and Google Scholar, with 54 peer-reviewed articles selected for synthesis. Fibers, fragments, films, and beads were the most frequently reported MP types, predominantly found in the digestive tracts, gills, and hepatopancreas of decapod crustaceans. These particles can cause oxidative stress, inflammation, reproductive disruption, and immune system impairment in crustaceans, while also acting as vectors for hazardous chemicals such as heavy metals and endocrine-disrupting compounds. The consumption of contaminated crustaceans poses potential health risks to humans, including gastrointestinal disorders, hormonal imbalances, and carcinogenic effects. Despite rapid progress in this field, major gaps remain in understanding the long-term ecological and human health impacts, particularly in less-studied regions and species. Further global investigations, long-term ecological assessments, and public awareness initiatives are essential. Effective mitigation will require interdisciplinary collaboration, technological innovation, and sustainable waste management to ensure a healthier marine ecosystem and safer seafood consumption.