A new study published Wednesday found that plastic debris in rivers could allow dangerous pathogens to hitch a ride downstream. Focusing on a British river, the study found that discarded plastic, wooden sticks and the water itself provided a breeding ground for communities of microorganisms, potentially creating a reservoir for bacteria and viruses known to cause human disease and antibiotic resistance.

“Our results suggest that plastic in freshwater bodies may facilitate the transport of potential pathogens and antibiotic resistance genes,” said lead author Vinko Zadjelovic from the University of Antofagasta in Chile.

“It could have indirect but important consequences for human health,” he told AFP.

Antibiotic resistance is a growing threat to public health. In 2019, infections due to antibiotic resistance killed an estimated 2.7 million people worldwide.

According to a study published in the journal MicrobiomeThey will cause 10 million deaths worldwide by 2050.

When plastic enters water, its surface becomes filled with nearby microbes within minutes. The researchers immersed the samples for a week in the River Sow in Warwickshire and below a sewage treatment plant in England’s West Midlands. They found significant differences in microbial communities depending on material samples.

Wastewater needs to be treated and disinfected to reduce the risk of microbes and the negative effects they can have on human health and the environment. But water samples collected by researchers in February 2020 contained human pathogens such as Salmonella, known as E.Coli, Escheria, and Streptococcus, which is responsible for strep throat.

Zadzhelovych said this underscores “the urgent need for tighter monitoring of wastewater treatment plants.”

Plastic and wooden samples, meanwhile, attracted “opportunistic” bacteria such as Pseudomonas aeruginosa and aeromonas, which are known to pose risks to people with weakened immune systems. P.aeruginosa, which causes infections in hospital patients, was found to be almost three times more abundant on “weathered plastic” that researchers manipulated to resemble the way plastic breaks down in nature, compared to wood.

This weathered plastic also showed a greater number of genes responsible for antibiotic resistance. British water companies have come under fire in recent months for pumping untreated sewage into UK waterways and under-reporting pollution, sparking widespread public outrage.

Rivers are the main pathway through which plastic enters the world’s oceans, sending between 3.5 thousand metric tonnes and 2.41 million metric tonnes of man-made material into the sea annually. Source