Microplastics in wastewater treatment plants carry intestinal viruses such as rotavirus up to three days and create significant health risks, a study finds.

Viruses can live in freshwater and infect humans for up to three days thanks to microplastics that come from wastewater plants, research has found.

Rotavirus, which causes diarrhoea and an upset stomach, was found to survive in lake water by attaching itself to the surfaces of tiny beads of plastic pollution, called microplastics, University of Stirling researchers said. 

The paper is published in the journal Environmental Pollution.

While previous research on virus transmission were held in sterile hospital settings, the University of Stirling study marks a first of its kind for exploring the spread of viruses with samples taken from the natural environment.

“We found that viruses can attach to microplastics, which allows them to survive in the water for three days, possibly longer,” Professor Richard Quilliam, lead researcher on the project, said.

“Even if a wastewater treatment plant is doing everything it can to clean sewage waste, the water discharged still has microplastics in it, which are then transported down the river, into the estuary and end up on the beach. We weren’t sure how well viruses could survive by ‘hitch-hiking’ on plastic in the environment, but they do survive, and they do remain infectious.”

The tiny plastic particles can be swallowed by swimmers or even by children who play on the beach, Quilliam said, warning that “it doesn’t take many virus particles to make you sick.”

The research was part of a Plastic Vectors project by Natural Environment Research Council (NERC), which allocated £1.85 million (around $ 2,24 million) to look into how plastics in the environment can contribute to the spread of bacteria and viruses, and their possible impacts on human health.

Microplastics in blood, seafood 

In a report in August 2019, the World Health Organization said microplastics contained in drinking water pose a "low" risk to human health at current levels, but more research is needed to reassure consumers. 

In recent years, however, researchers found dangers of microplastics. 

The latest findings were the latest of ever-increasing studies on how plastic pollution affects the environment and human health.

Research in February 2021 found that 386 marine fish species, including many that humans eat, are consuming plastic particles amid an increase in plastic pollution. 

Last March, Dutch scientists found tiny fragments of plastics in human blood for the first time. Published in the journal Environment International, the study examined blood samples from 22 healthy volunteers and found microplastics in nearly 80 percent of them.

Microplastics entering the human body are not without long-term side effects.

Last December, engineers at Rice University found that styrofoam, a form of polystyrene, a synthetic polymer, was broken down into microplastics and contributed to antibiotic resistance. Resistance to medicine causes illnesses to become more dangerous, costly and harder to treat.

In a critical milestone that was hailed for being one of the world’s most ambitious environmental actions since the 1989 Montreal Protocol, the United Nations has initiated a treaty to fight plastic pollution. 

Source: TRT World