Tiny bits of plastic in drinking water pose a low health risk to people — for now, concluded a Wednesday report from the World Health Organization, which called for a reduction in plastic pollution to limit the future dangers of such “microplastics.”
We live in an age of plastic, with more than 300 million tons of the imperishable stuff produced every year, found in bags, bottles, and every human-made object imaginable. They all shed millions and billions of tiny particles in the environment, researchers have found in the last decade, a discovery that led to the WHO report.
“We urgently need to know more about the health impact of microplastics because they are everywhere — including in our drinking water,” WHO’s Maria Neira said in a statement on the report.
One research team last year reported that 90% of bottled water sampled contained microscopic plastic fibers, for example, capping a series of studies making similar findings in air, water, and food. Drinking water studies have found microplastic concentrations ranging from 1,000 to .001 microparticles per liter, according to the report, with much variability in how particles were defined.
Looking for health risks, the WHO report tallied 50 recent studies that looked at the balance of chemical, physical, and infection-related risks of drinking these particles. Microplastics contain chemicals that could potentially harm organs if released in high concentrations, such as flame retardants, or they might cause injuries simply by gumming things up. As well, they could act as niches for harmful bacteria. At the same time, the digestive system is well-practiced at removing harmful material from the body.
“Microplastics in drinking water don’t appear to pose a health risk at current levels,” said Neira, on balance. “But we need to find out more.”
“My concern relates to the future,” study coauthor Bart Koelmans of Wageningen University in the Netherlands told BuzzFeed News, as plastic becomes even more concentrated in the environment. Even less is known about “nano”-scale plastic particles about the size of molecules and whether they pass as easily through the digestive tract as merely microscopic particles.
Those concerns are real because worldwide plastics production is projected to quadruple by 2050, Penn State chemist Sherri Mason, who was not part of the report, told BuzzFeed News. “I see microplastics as the canary in the coal mine,” Mason said. “I appreciate the study’s conclusion of a low health risk right now, but we have to bear in mind that it is only looking at drinking water, not everything else with plastic in it, and that its call to reduce plastic pollution is the message people need to hear.”
In particular, the report called for halting “single use” plastic products, such as bags, bottles, and other throwaway items now cluttering landfills and oceans everywhere. “We are trying to take a lot of lessons from climate change,” Mason said. “We have a problem that we are better addressing now instead of waiting 30 years to try and fix.”
Wastewater plants can remove about 90% of the microplastics in water, but two-thirds of the population in low- and middle-income countries lack basic sewer connections to them. Routine monitoring of microplastics in drinking water is not recommended by the report in the face of the need to build these connections, which will perform the dual purpose of limiting widespread intestinal illnesses and proliferating microplastics.
“There is no silver bullet solution. It is a combination of things” to reduce microplastics, Koelmans said. “Good studies are underway. Still, they and follow-up studies need effort. And we will need years before the most pressing questions are answered.”