How Many Microplastics Are Being Ingested by Fish?

Eating fish and seafood is an important part of maintaining a healthy diet. Not only is fish a rich source of protein that’s low in calories, but it’s also high in Omega-3 fatty acids. This latter ingredient is especially important, since Omega-3 is an essential fat that the body is not capable of producing on its own. What’s more, Omega-3 isn’t found in plentiful supply in many other foodstuffs.

Essential fats like Omega-3 help protect the heart, prevent strokes and could be beneficial to our overall health in a variety of different ways. But while eating fish is good for your health on the whole, there is one small caveat to that statement – a very small one, in fact. Microplastics. At less than 5mm in diameter, these tiny particles of plastic can be mistaken for food by marine animals and become ingested, thus infiltrating the food chain of which we humans sit proudly atop.

Plenty of microplastics in the sea

The amount of plastic waste that is deposited into our seas and oceans on a daily basis is quite frightening. Over time, the elements break these substances down into far smaller particles, known as microplastics, which are invisible to the human eye. According to the UN, there were 51 trillion pieces of microplastics in the ocean in 2017, which is more than 500 times more stars there are in our galaxy, the Milky Way.

That figure doesn’t look like shrinking any time soon, either. A growing population and increased consumption of plastic goods means that the amount we discard is on the increase, especially in the wake of COVID-19. One of the more concerning environmental implications of coronavirus has been the sharp upturn in the number of single-use personal protective equipment (PPE) items being used and thrown away, including gowns, face masks and gloves.

Fish under threat

Research into how many microplastics are ingested by fish – and how dangerous microplastics are – is still in its infancy. To date, studies have discovered relatively small amounts of the substance inside the bodies of marine dwelling animals, meaning that the accumulative effect of these particles is unlikely to have serious consequences for human consumption. By the time a serving of fish arrives on your dinner table, there are thought to be five or fewer microplastic particles in it.

But just because the ingestion of microplastics isn’t a direct concern for humans, that doesn’t mean it can’t harm animals. At the very least, these small particles are ingested by fish and crustaceans, occupying valuable space in their stomachs but failing to provide any nutritional benefits, or else interfering with their respiratory systems by clogging up their gills. What’s worse, the microplastics can also bond with more harmful particles in the ocean, including pesticides and PCBs. As such, we might not know exactly how many microplastics are being ingested by fish – but we know for sure that it’s too many.