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We have all heard of how plastics can injure wildlife – straws getting stuck in sea turtles’ nostrils; sea bird deaths due to starvation and malnourishment from ingesting plastics and such. Unfortunately humans are not spared either, microplastics could be in our seafood dinners too!

Microplasitcs are the result of larger pieces of plastic breaking down after being exposed to sunlight and since they range from 1-5mm in diameter, not all fish can distinguish them. Ingestion of these tiny particles can start from the very bottom of the food chain, with zooplankton.

Here is a quick video demonstrating the behaviour in zooplankton. The narrator also explains bioaccumulation and gives a brief look into the plastic problem in the oceans. Of course the larger sized plastic are also confused for food and get swallowed up by larger fish. A classic example is the mistake turtle make when trying to distinguish between a plastic bag and a jellyfish.

A team of researchers were curious about whether they could find actual plastic pieces in fish species widely consumed by humans. They  collected samples (both fish and shellfish) from Indonesia and California across 11 and 12 species of fish respectively. They found anthropogenic marine debris in 28% and 25% of the respective collection of samples. These are species like Herring, Indian Mackeral, Chinook Salmon, Striped bass and more (Rochman et al., 2015), species that humans eat. They mainly found harder plastic in the fish from Indonesia and textile fibre-like debris in the fish from California.

If these numbers start growing, it could impact countries whom rely on fishing as their major livelihood – from the biggest fisheries to the small village. This could also spell trouble for global food security if humans can get sick from ingesting seafood ridden with plastics.

References:
Rochman, C.M., Tahir, A., Williams, S.L., Baxa, D.V., Lam, R., Miller, J.T., Teh, F., Werorilangi, S. & Teh, S.J. 2015, “Anthropogenic debris in seafood: Plastic debris and fibers from textiles in fish and bivalves sold for human consumption”, Scientific Reports (Nature Publisher Group), vol. 5, pp. 14340.

Seltenrich N. (2015). New link in the food chain? Marine plastic pollution and seafood safety. Environmental health perspectives, 123(2), A34–A41. https://doi.org/10.1289/ehp.123-A34