Microplastics in fishmeal: A threatening issue for sustainable aquaculture and human health

Plastic pollution is a global concern, leading to the abundance of macro- and microplastics (MPs) in the marine environment and subsequent accumulation in many marine organisms, particularly small pelagic and oceanic fish species. These small fishes are usually considered as the non-target catch or by-products of marine capture fisheries. However, these by-catch fishes convert into fishmeal due to their excellent nutritional value, and thereby, it used as the primary ingredient of artificial feeds for aquaculture and livestock animal production. The fishmeal and fish feed facilitates MPs’ entry into the aquaculture systems when the MPs−contaminated feeds are supplied to cultured fish for regular feeding. Thus, MPs get access to interact with the elements of the culture pond ecosystem and leading to subsequent alterations in the physiological and behavioral attributes of cultured fishes. Consequently, MPs may accumulate in the edible portions of cultured fishes, which may cause severe physiological disorders in fish consumers. Thus, human exposure to MPs becomes a significant threat to global public health. Therefore, this review discussed the factors associated with MPs’ introduction to the aquaculture systems via fishmeal. In addition, this article enlightened the possible consequences of MPs on the pond ecosystem, cultured fish physiology, and consumer health. We hypothesized that the growing concern among people about MPs might be impacted the demand for aquaculture goods. This study recommended taking necessary steps towards improving the MPs’ screening process during fish feed production and focusing on more exclusive studies to elucidate the impacts of MPs on sustainable aquaculture production.