We are drinking lots of plastics, reveals a new study

According to scientists, every day about eight trillion pieces of microplastics go through wastewater treatment plants and end up in the aquatic environment

Researchers from Washington State University (WSU) have discovered that tiny, nanoscale particles of the most commonly used plastics tend to make their way into the water supply, especially in freshwater, or settle out in wastewater treatment plants, or end up like sludge in landfills and often as fertilizer.

The study, published in the journal Water Research, examined what happens to these nanoscale plastics that are making their way into the aquatic environment. "We are drinking lots of plastics," said Indranil Chowdhury, study co-author from WSU, who led the research. "We are drinking almost a few grams of plastics every month or so. That is concerning because you don't know what will happen after 20 years," Chowdhury said.

According to scientists, every day about eight trillion pieces of microplastics go through wastewater treatment plants and end up in the aquatic environment. These little bits of plastic, they said, can come from the degradation of larger plastics or from microbeads that are used in personal care products.

In their study, the scientists studied the fate of nanoparticles of polyethylene and polystyrene, which are used in a huge number of products, including plastic bags, personal care products, kitchen appliances, disposable drinking cups, and packaging material. They assessed how the tiny particles behaved under various conditions, ranging from salty seawater to water containing organic material. "We're looking at this more in a fundamental way," Chowdhury said. "Why are they becoming stable and remaining in the water? Once they're in different types of water, what makes these plastics remain suspended in the environment," he said.

While the acidity of water has little impact on what happens to nanoscale plastics, the study found that salt and natural organic matter are important in determining how the plastics move or settle. Chowdhury cautioned that the tiny plastics are staying in the environment with unknown health and environmental consequences. "Our drinking water plants are not sufficient at removing these micro and nanoscale plastics. We're finding these plastics in the drinking water but we don't know why," he said.

"Reuse plastics as much as possible," the WSU scientist said.