New research has shown that marine mollusks such as shellfish, oysters and caps contain the highest level of microplastic contamination of all seafood.
The team, led by members of Hull School of Medicine and Hull University, analyzed over 50 studies on the topic of microplastic contamination in seafood. Published between 2014 and 2020, they have worked with species from fish to shellfish around the world.
“A critical step in understanding the full impact on human consumption [of plastics] is the first complete determination of microplastic levels [MPs] people swallow, ”says Evangelos Danopoulos, a graduate student at Hull School of Medicine and co-author of the article. “We can start doing this by looking at how much seafood and fish is eaten and by measuring the number of messengers in those creatures.”
Microplastics are formed by the decay of larger plastic particles as they slowly decompose; some are produced directly as cleaning additives or cosmetics. Eventually, through the wastewater, they are directed to watercourses and the ocean. Once there, MPs are often swallowed up by wildlife that confuses them over bits of food. Microplastics resist digestion and accumulation in animal bodies.
Whenever we eat seafood, we also take the plastic they have ingested throughout their lives. Contamination of MP is not limited to seafood, but is more pronounced here than in any other type of environment. The team found that the content of microplastics ranges between 0-10.5 microplastics per gram (MP / g) in mollusks, 0.1-8.6 MP / g in crustaceans, 0-2.9 MP / g in fish.
“Microplastics have been found in various parts of organisms, such as the gut and liver,” says Danopoulos. “Types of seafood such as oysters, shellfish and caps are consumed whole, while larger fish and mammals consume only parts. Therefore, understanding microplastic contamination of certain parts of the body and their consumption by humans is crucial. “
“No one yet fully understands the full impact of microplastics on the human body, but early evidence from other studies suggests they are causing harm.”
China, Australia and Canada are the world’s largest consumers of mollusks, the team found, followed by Japan, the US, Europe and the UK. Those trapped along Asian coasts had the highest levels of contamination, suggesting that these areas are most polluted by plastics and microplastics.
The findings show the wide range of plastic pollution problems facing our planet. Production of such materials is expected to triple by 2060, which means it will get worse and worse in the future if no steps are taken soon. However, for this to happen, we need to get a clearer picture of the problem, and the team explains that we need standardized methods for measuring microplastic contamination levels and more field data to see how they affect different oceans and watercourses from them.
The journal “Microplastic contamination of seafood intended for human consumption: a systematic review and meta-analysis” was published in the journal. Environmental health perspectives.