How do microbeads affect fish?

Asked by: Susie Adams, Portsmouth

There’s no doubt that fish and other aquatic animals eat plastic fragments (under 5mm). These include ‘microbeads’ that are added to toiletries and household products, as well as fibres washed from synthetic clothing. A recent study found three-quarters of flatfish in the River Thames have eaten microplastics. Even deep-sea animals have synthetic fibres in their guts. The impacts of this are complex. Some animals suffer from blocked digestive tracts, leading to starvation. Another concern is poisoning from microplastics coated in toxic chemicals. There’s still much we don’t know about exactly how plastics and toxins accumulate in food webs.

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