the sciences. Microplastics are Trojan horses for marine bacteriaبكتيريا

Madrid, 27 years old (European press)

The importance of microplastic accumulation in food may be underestimated and there is also a risk of introducing harmful bacteria common in coastal waters into the food chain.

Researchers at the University of Portsmouth tested a theory that microplastics covered with a biofilm (much like natural algae) were more likely to gobble up oysters than microplastics that were perfectly clean. Although the experiment was conducted with oysters under laboratory conditions, the scientists believe that similar results can be found in other edible marine species that also filter seawater for food.

So far, studies that have been conducted to test the effects of microplastics on marine life have typically used clean, virgin microplastics. However, this is not representative of what is happening with microplastics in the marine environment. Bacteria easily colonize microplastics that enter the ocean.

In this study, published in Science of the Total Environment, scientists compared the absorption rates of clean microplastics versus microplastics with E. coli biofilm coatings. The results were worrying: the oysters contained 10 times more plastic particles when exposed to pearls covered with a biofilm. Presumably, these coated particles look more like shellfish food, which explains their preferential intake over clean microplastics.

Scientists say the implications for the food chain are worrying. Eating microplastics is not only harmful to shellfish, but also affects human health. The plastic in marine animals does not degrade and is consumed when we eat it.

Troyan horses

Lead researcher Dr Joanne Preston, Lecturer in Marine Ecology and Evolution at the University of Portsmouth, said: “What we discovered is that microplastics are in fact a Trojan horse in the marine world. We found that clean plastics had little impact on breathing and feeding rates for oysters, but It had an effect when I fed them with microplastics hidden in the biofilm. The oysters took more and affected their health. It is not known exactly how much this affects the food chain, but no, perhaps because the organisms ingest more plastic and potentially disease-causing organisms, this will have a negative effect in the Ultimately on human health. We know that microplastics may be the mechanism by which bacteria concentrate in coastal waters and this indicates that shellfish are easily absorbed and can be transferred to humans or other marine life.”

Dr. Preston says they have “successfully tested a hypothesis; this opens the door to further research on environmentally relevant studies of the long-term effects of microplastics encapsulated in biofilms on a larger scale of marine life. We also need to study the transport of microbes in the food chain through plastic in greater detail.” much.”

Professor Steve Fletcher, Director of the University’s Plastics Revolution Initiative, says, “The results of this research provide us with more information about the potential harm that microplastics have on the food chain. It shows how we can greatly reduce the impact of microplastics in the food chain. Microplastics Exists. It is clear that further studies are urgently needed.”