Anthropogenic debris in seafood: Plastic debris and fibers from textiles in fish and bivalves sold for human consumption

Abstract

The ubiquity of anthropogenic debris in hundreds of species of wildlife and the toxicity of chemicals associated with it has begun to raise concerns regarding the presence of anthropogenic debris in seafood. We assessed the presence of anthropogenic debris in fishes and shellfish on sale for human consumption. We sampled from markets in Makassar, Indonesia, and from California, USA. All fish and shellfish were identified to species where possible. Anthropogenic debris was extracted from the digestive tracts of fish and whole shellfish using a 10% KOH solution and quantified under a dissecting microscope. In Indonesia, anthropogenic debris was found in 28% of individual fish and in 55% of all species. Similarly, in the USA, anthropogenic debris was found in 25% of individual fish and in 67% of all species. Anthropogenic debris was also found in 33% of individual shellfish sampled. All of the anthropogenic debris recovered from fish in Indonesia was plastic, whereas anthropogenic debris recovered from fish in the USA was primarily fibers. Variations in debris types likely reflect different sources and waste management strategies between countries. We report some of the first findings of plastic debris in fishes directly sold for human consumption raising concerns regarding human health.

Figure 1. Map of sampling locations.

Samples of fish and shellfish (152 total samples) sold for human consumption were collected August through November of 2014 from local fish markets and/or fishermen in Makassar, Sulawesi, Indonesia (bottom left) and Half Moon Bay, California, USA (bottom right). Map produced using the open-source software R library “mapdata” and Global Administrative Areas (GADM) database.

Figure 2. Anthropogenic debris recovered from fish sampled from the USA and Indonesia.

The graph on the left (a) shows the proportion of individual fish sampled in each location that contained anthropogenic debris (black) in their GI tract. The middle bar (white) shows the proportion with plastic debris and the right bar (diagonal lines) shows the proportion with fibers. The graph on the right (b) shows the total number of pieces of anthropogenic debris (black) found across all fish from each location. The middle bar (white) shows the total number of pieces of plastic debris and the right bar (diagonal lines) shows the total number of fibers.

Figure 3. Types of anthropogenic debris in market fish products sampled from Indonesia and the United States.

The pie charts above show the percentage of each type (i.e. plastic fragments, fibers, plastic film, plastic foam and plastic monofilament) of anthropogenic debris found across all fish sampled from Indonesia (top) and the United States (bottom). Images show examples of each type of debris found. Scale bars on all pictures are set at 500 μm.