Research: Microplastics entering human food chain

A Flinders University study has found microplastics in variable concentrations in blue mussels in South Australia.

According to the researchers, this means microplastics are now finding their way into human food supplies — including wild-caught and ocean-farmed fish and seafood sourced from the once pristine Southern Ocean and gulf waters of South Australia.

“Our findings shed light on the urgent need to prevent microplastic pollution by working with the communities, industries and government to protect these fragile marine systems,” said Professor Karen Burke da Silva, senior author of the study.

“Low to medium levels of microplastics (less than 5 mm in size) measured in the common blue mussel (Mytilus spp.), a filter feeder affected by ecosystem conditions, were measured to analyse the main kinds of pollution affecting the environment, and single-use plastic was the main offender.”

For the study, published in Science of the Total Environment, samples of microplastics were taken from a number of popular beaches across South Australia. Mussels near larger towns and cities were found to contain higher levels of microplastics than those in less populous areas.

The forms of plastic commonly discovered were polyamide (PA), polyethylene (PE), polypropylene (PP), acrylic resin, polyethyleneterephthalate (PET) and cellulose, which the researchers suggest come from single-use, short lifecycle products, fabrics, ropes and cordage from the fishing industry.

“The areas examined include some biodiversity hotspots of global significance — including the breeding ground of the Great Cuttlefish in the Northern Spencer Gulf and marine ecosystems more diverse than the Great Barrier Reef (such as Coffin Bay), so clean-up and prevention measures are long overdue,” Burke da Silva said.

“Apart from the harvesting of blue mussels, we also need to consider the impact of microplastic particles entering other parts of the human food chain with microplastic pollution expected to increase in the future.”

Image credit: ©stock.adobe.com/au/Jose