Concerning Levels of Microplastics Have Been Found in Oysters and Mussels

A first-of-its-kind study has detected fiberglass particles in oysters and mussels collected from a harbor on England’s south coast. Researchers from the University of Brighton and the University of Portsmouth published their findings in the Journal of Hazardous Materials. 

According to the study authors, oysters and mussels were caught in Chichester Harbour over a six-month period between December 2018 and May 2019, in an area downstream from an active boatyard. After analyzing the bivalves, the oysters were found to have up to 11,220 fiberglass particles per kilogram — and the mussels had 2,740 particles per kilogram. 

The amount of fiberglass found in the oysters and mussels was at its highest during the winter months when a number of boats were being repaired at the nearby boatyard. (Fiberglass is used in the construction, repair, and maintenance of boats including “yachts, ships and fast rescue lifeboats, fishing vessels, and cruisers,” according to the study authors. It is so prevalent, that almost 80% of the hulls of boats less than 65 feet long have been constructed using fiberglass.) 

Regardless, the authors said that this was the first time that fiberglass particles had been detected in the food chain. Bivalves like oysters and mussels are filter feeders, taking in water through their gills. According to Oyster Heaven, a marine conservation organization that repopulates oyster reefs, oysters’ gills are lined with tiny hairlike structures called cilia that separate nutrients and edible particles from the water; any solids are then transported to the oyster’s mouth, and the water is expelled. 

This style of eating also leaves oysters susceptible to taking in these fiberglass particles, which can affect their ability to eat and digest food, cause other physical injuries, or even kill them. “This not only affects marine life but could also have significant implications for human health, given that these bivalves often end up on our plates,” the University of Portsmouth added in a statement. 

Because this is a newly published and original area of study, there is no information about what those “significant implications” could be. The presence of other microplastics — not solely the ones derived from fiberglass — in the human body is an emerging study area, and new and ongoing research continues to broaden our understanding of how this can affect our health.  

An unrelated study, which was published in March in the New England Journal of Medicine found that patients being treated for heart disease were almost twice as likely to have a heart attack or stroke if microplastics were detected in the walls of their carotid arteries than patients that did not have microplastics in their blood vessels. Additionally, the patients in which microplastics were present were at increased risk of death within the next three years. Another study, published in May in the journal Toxicological Sciences, said that microplastics have been detected in human testicles, with researchers suggesting that this could impact the reproductive system. 

Oysters and mussels aren’t the only marine life affected by those tiny fiberglass particles. “We identified fiberglass embedded in other organic material floating in the water, like seagrass and seaweed fragments [and] small snails,” Corina Ciocan, one of the study authors and marine biology lecturer at the University of Brighton, told Newsweek. 

The study authors said that further research is needed to determine the “potential transfer up the food chain” and the effect that this contamination could have on humans.

“It’s a stark reminder of the hidden dangers in our environment,” Ciocan said.