Ingestion of plastic debris by commercially important marine fish in southeast-south Brazil

Rising concentrations of plastics in the oceans are leading to increasing negative interactions with marine biota, including ingestion by endangered and/or economically important seafood species such as fish. In this paper, we visually evaluated plastic debris ingestion by 965 specimens of eight commercially exploited fish species from different marine habitats off the southeast-south coast of Brazil. All species ingested plastics, with pelagic animals having higher amounts, frequency of occurrence, diversity and sizes of ingested items than demersal-pelagic and demersal animals. Highest frequency of occurrence (FO%) of plastic ingestion (25.8%) was observed for the pelagic skipjack tuna Katsuwonus pelamis (Scombridae), and lowest (5%) for the demersal bluewing searobin Prionotus punctatus (Triglidae). Microplastics predominated in all species, and fibers/lines and fragments were the main items found, possibly derived from fishing materials. The most abundant plastic colors were transparent, black and blue, and the most common polymers were polyamide and polyurethane. With the available data, no relationship between the size of the individuals and amount of ingested plastics was observed. Considering the negative impacts of plastic ingestion on marine fish, and potentially on human health due to their consumption, understanding ingestion patterns is critical for better evaluating their origin and possible causes, and consequently for helping define prevention strategies for this problem.