Highest levels of microplastics found in molluscs
University of York
Mussels, oysters and scallops have the highest levels of microplastic contamination among seafood, a new study reveals.
Scientists are still trying to understand the health
implications for humans consuming fish and shellfish contaminated with
microplastics.
The study - led by researchers at the joint medical school of the
Universities of Hull and York (Hull York Medical School) - looked
at more than 50 studies between 2014 and 2020 to investigate the levels of
microplastic contamination globally in fish and shellfish.
Scientists are still trying to understand the health implications
for humans consuming fish and shellfish contaminated with these tiny particles
of waste plastic, which finds its ways into waterways and oceans through waste
mismanagement.
Human body
Study author, Evangelos Danopoulos, a postgraduate student
at Hull
York Medical School said: “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.
“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.”
The study shows microplastic content was 0-10.5 microplastics per
gram (MPs/g) in molluscs, 0.1-8.6 MPs/g in crustaceans, 0-2.9 MPs/g in fish.
The latest consumption data in the research shows China,
Australia, Canada, Japan and the US are amongst the largest consumers of
molluscs, followed by Europe and the UK.
Contaminated
Molluscs collected off the coasts of Asia were the most heavily
contaminated with researchers suggesting that these areas are more heavily
polluted by plastic.
Evangelos Danopoulos added: “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.”
Plastic
Plastic waste generated worldwide is expected to triple to 155–265
million metric tonnes per year by 2060. Once the plastic finds its way
into oceans, lakes and rivers it has the potential to end up as microplastic
inside shellfish, fish and marine mammals.
The research points to the need to standardise methods of
measuring microplastic contamination so that different measurements can be more
readily compared. Researchers said more data is needed from different parts of
the world to understand how the issue varies between different oceans, seas and
waterways.