A team of scientists has discovered a new source of dangerous chemical pollution: the rechargeable lithium-ion batteries found in most electric cars.
Some lithium-ion battery technologies use a class of chemicals called PFAS, or polyfluoroalkyl substances, which help make batteries less flammable.
PFAS are known as “forever chemicals” because they quickly accumulate in the environment and the bodies of people and animals, and do not break down for thousands of years.
It has been linked to a range of health conditions, including liver damage, high cholesterol, low birth weight and chronic kidney disease.
Scientists found high levels of PFAS in air, water, snow, soil and sediment samples near laboratories that make the chemicals, in the United States, Belgium and France, according to a peer-reviewed study in the journal Nature Communications.
“Reducing carbon emissions with innovations like electric vehicles is critical, but the side effect of increased PFAS contamination is something to be wary of,” said Jennifer Guelfo, associate professor of environmental engineering at Texas Tech University.
The study explained that this issue is of global concern, because lithium-ion batteries are used all over the world.
The specific class of PFAS that Guelfo's team found is called bis-perfluoroalkyl sulfonimides, or bis-FASIs.
The scientists tested more than a dozen lithium-ion batteries used in electric vehicles and consumer electronics, such as laptops, and found bi-FASI at different concentrations.
It's hard to know how prevalent the chemicals are in particular lithium-ion batteries because there's not enough research yet, said Lee Ferguson, an assistant professor of environmental engineering at Duke and a co-author of the study.
Air emissions data indicate that chemicals can migrate to areas far from manufacturing sites. They can also leak into the environment from landfills, where most lithium-ion batteries end up.
The study revealed that only about 5% of lithium-ion batteries are recycled, and by 2040, there could be about 8 million tons of lithium-ion battery waste.
Bis-FASIs are comparable to “older” chemicals like PFOA, in part because they are more difficult to break down, Guelfo said.
This study represents the first “cradle-to-grave” assessment of the environmental impacts of bi-FASI use in lithium-ion batteries. The effects of bis-FASIs on humans have not yet been studied.