Microplastics Found in 75% of Fish Meant for Human Consumption: Is It Still Healthy to Eat Seafood?

Scientists have discovered that a significant portion of fish, 75%, intended for human consumption may contain microplastics.

One expert stated that whether or not one chooses to consume fish is a "personal choice."

Until now, seafood has generally been regarded as a healthy choice but the study raises the question of whether this still holds.

Three-quarters of fish caught off the southern New Zealand coast were found to have some microplastic in their tissues, according to a recent study.

Microplastics are minute pieces of plastic with a diameter of less than 0.2 inches.

Isabella Clere, the lead author of the study said that She sampled fish, and found that 75% of them had consumed microplastic.

She collected fish samples over two years in all seasons along the southern Aotearoa coast of New Zealand, from Oamaru all the way to Te Waewae Bay.

Clere is also a coastal scientist.

She claimed that she discovered a similar ingestion rate in both benthic, or bottom-dwelling fish, and pelagic, or surface-dwelling fish, indicating that plastics are pervasive throughout the water column and an ongoing aspect of the ocean.

From Cosmetics and Clothing to Fish Guts

Some microplastic particles are designed for use in cosmetics or microfiber clothing, while others are the result of the breaking down of larger parts of plastic.

The upper oceans of the world contain between 82,000 and 578,000 tons of microplastic, or approximately 24.4 trillion pieces, according to a 2021 estimate from a study that was recently published.

Most marine organisms consume these microplastics, which is how they enter their systems.

According to Clere's research from New Zealand, 391 microplastic fragments were found in the 155 fish from 10 different species that were examined.

The size of 98% of the microplastic particles was less than 3mm.

Bridie Allan, a co-author of the study said in a University of Otago statement, that they examined a variety of pelagic and benthic fish and discovered microplastics in the guts of every species, indicating that these particles are present in all oceanic layers.

She added that the majority of the plastic types found in a sample of randomly chosen fish guts were polyethylene, viscose, polypropylene, and plastic additives.

The most widely used plastic and the plastic that is most frequently found in the world's oceans are both polyethylenes.

This means that the presence of microplastic particles in the southern waters is a persistent phenomenon because the fish were picked up over the course of a year rather than at one particular time point.

Read also: Microplastic Pollution: California State Government Adopts Strategy of Microplastic Cleanup 

Microplastics vs Animal Health

Although numerous microplastics have been discovered in fish all over the world, the New Zealand study is the first to document a similar pattern in the Southern Hemisphere.

Clere said that global studies on fish microplastics have produced results that are comparable to their study.

The majority of studies on marine microplastic pollution have been conducted in the Northern Hemisphere and near oceanic gyres, with little research conducted in the Southern Hemisphere.

Large systems of circular ocean currents known as ocean gyres are formed by the Earth's rotational forces and wind patterns.

Microplastics bioaccumulate and become more concentrated in the tissues of predators as they move up food chains.

According to Scientific American, this could be harmful to the health of the animals because microplastic particles carry pollutants on their surface and can harm organs by rubbing against organ walls and livers.

Clere said that generally speaking, there is a higher risk of secondary transfer of plastics with seafood that is consumed wholes, such as anchovies, sardines, and shellfish.

She added that a variety of chemicals are also present in plastics, some of which could be consumed by people.

However, there hasn't been a lot of research done to date that has examined the dangers connected with the secondhand transfer of chemicals from plastics to humans.

Plastic Use and Misuse

Clere stressed in an interview the need to be mindful of plastic use, potential misuse, and how that's affecting the environment and adversely harming humans, but in terms of eating it, that's just a matter of personal preference.

The human body is also being increasingly found to contain microplastics.

Microplastics were first discovered in human blood in a 2022 study.

Dick Vethaak, an ecotoxicologist from Vrije Universiteit Amsterdam in the Netherlands, said that it is understandable to be worried.

The particles are dispersed throughout the body and are present. In general, babies and young children are more susceptible to chemical and particle exposure, he continued.

Vethaak is the author of the blood study, Newsweek reported.

Related article: Robotic Fish That Sucks Microplastics from Waters Could Address Earth's Growing Microplastic Pollution