Fresh oysters in a white plate with ice and lemon

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YORK, United Kingdom — Heading to a holiday party? You may want to think twice before loading your plate up with seafood appetizers. A new study finds microplastic contamination may be making these foods unsafe for human consumption. Researchers at the Universities of Hull and York warn mussels, oysters, and scallops have the highest levels of microplastics among all seafood tested.

The study reviewed over 50 previous reports on microplastic contamination in both fish and shellfish between 2014 and 2020. Compared to fish and crustaceans, mollusks (mussels, oysters, and scallops) have higher rates of microplastics per gram in their bodies. Study authors say they are still trying to uncover all of the possible health implications humans may face from eating seafood laced with plastic particles. Researchers do know this contamination stems from waste mismanagement which enters local waterways and the ocean.

“No-one yet fully understands the full impact of microplastics on the human body, but early evidence from other studies suggest they do cause harm,” says Evangelos Danopoulos, a postgraduate student at Hull York Medical School, in a university release.

“A critical step in understanding the full impact on human consumption is in first fully establishing what levels of microplastics (MPs) humans are ingesting. We can start to do this by looking at how much seafood and fish is eaten and measuring the amount of MPs in these creatures.”

Microplastic contamination only going to get worse

The results reveal mollusks contain between zero and 10.5 microplastics per gram (MPs/g). That number is only between 0.1-8.6 MPs/g for crustaceans and 0-2.9 MPs/g for fish.

Consumers in China, Australia, Canada, Japan, and the United States tend to eat the largest amounts of mollusks. Researchers also find mussels, oysters, and scallops collected off the coasts of Asia suffer the highest amounts of microplastic contamination.

“Microplastics have been found in various parts of organisms such as the intestines and the liver. Seafood species like oysters, mussels and scallops are consumed whole whereas in larger fish and mammals only parts are consumed. Therefore, understanding the microplastic contamination of specific body parts, and their consumption by humans, is key,” Danopoulos adds.

The British team expects the amount of plastic waste created globally to triple by the year 2060; reaching 155 to 265 million metric tons. Once those particles reach bodies of water, they’ll have the potential to end up inside the shellfish and marine animals humans fish for.

The study appears in the journal Environmental Health Perspectives.

About Chris Melore

Chris Melore has been a writer, researcher, editor, and producer in the New York-area since 2006. He won a local Emmy award for his work in sports television in 2011.

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