Research & Discovery

Microplastics Are in Our Food, Water and Air. Should We Be Worried?

Microplastics are everywhere and in everything, including humans – and that’s not a good thing.

Microplastics are fragments of plastic less than 5 millimeters in size that usually require a microscope to see. Studies have shown the negative effects of microplastics and their even smaller cousins, nanoplastics, on human and animal respiratory and cardiovascular health.

Bryan Berger, an associate chemical engineering professor at UVA, researches the impact of forever chemicals and microplastics in the environment. (Photo by Matt Riley, University Communications)

Unfortunately, because they are so widely used and spread in human industry, they are impossible to avoid, even for plants.

A study released this month showed that microplastics severely impair the global photosynthesis rate. Researchers found that exposure to microplastic pollution “leads to a global reduction in photosynthesis of 7.05% to 12.12% in terrestrial plants, marine algae and freshwater algae,” researchers published in the Proceedings of the National Academy of Sciences.

“Global crop production is losing hundreds of millions of tons of agricultural output a year because microplastics impair photosynthesis in plants,” said Bryan Berger, a University of Virginia chemical engineering professor looking into what levels of exposure might mean and how to phase out some microplastics. “At a time when food scarcity is already a challenge and we have a changing climate, the pervasiveness of this is directly impacting our agricultural capacity.”

Reducing exposure means thinking a lot about how you eat and minimizing the use of plastic in the food you’re eating and its packaging

In terms of our major sources of exposure, he said that microplastics are like “forever chemicals” known as PFAS in that they are ubiquitous, from our water to our soil. “Most of the food we eat and the water we drink contains microplastics,” he said.

They may even be in the tea you drink. Tea bags often contain plastic that seeps into the beverage as they steep. A 2019 study found that a single cup of tea prepared from a tea bag made with plastic could contain about 2.3 million micro-sized plastics.

“Reducing exposure means thinking a lot about how you eat and minimizing the use of plastic in the food you’re eating and its packaging,” said Berger, who recommends swapping those teabags for loose-leaf tea. (The U.S.-based nonprofit the Center for Environmental Health has created a list to help shoppers identify whether their tea bag brand contains plastic.)

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Ironically, synthetic materials in home water filters could also be a source of microplastics. “Maybe activated charcoal filters or nonsynthetic material-based water filters could be more effective,” he said.

Berger is currently measuring microplastic contamination in residential water and wastewater. He investigates the “plastisphere,” the ecosystem created by human-made plastics in the environment, and particularly aquatic environments, where microorganisms like bacteria and fungi thrive.

“Microplastics that are present in water provide a hospitable place for microbes to grow, in particular pathogens,” he said. “So, they end up accumulating things like PFAS and heavy metals and become antimicrobial resistant. If that ends up in your drinking water, that can be potentially unhealthy.”

Berger said regulations on plastic use are rapidly evolving. Part of the challenge is that plastics are so ubiquitous in our daily lives, it’s hard to regulate. Something like PFAS, he notes, is a more specialized chemical and thus a less complex battle.

He said he does see more awareness about food packaging and other ways plastics find their way into our food supply, and welcomes more research on measuring the global agricultural burden.

“The first thing to do is go to the food supply and investigate the roots of entry of crops and water,” he said. “That work includes changing packaging and the way things are delivered.”