Water reacts with plastic to create harmful particles, new study finds
The chemical reaction creates particles that damage red blood cells and proteins, raising health concerns.
Plain water could be responsible for making plastics harmful to people, according to a new study published Thursday in the scientific journal Nature.
The study found chemical reactions between water and six types of fossil fuel-based plastic created particles that damaged red blood cells and proteins in laboratory tests.
"Is this phenomenon 5% responsible or 90% responsible for the health effects we are seeing, I can’t answer," said co-author Wei Min, a Columbia University chemist. "But I would be surprised if it doesn’t play any role."
READ MORE: Elephant carcasses enrich savannah soil for years after death, study finds
READ MORE: Infections caused one in eight global cancer cases in 2024, study finds
As plastic in the body breaks down into smaller bits known as microplastics and nanoplastics, the potential danger increases, Min said.
Interactions between water and plastic could help explain why other studies have shown microplastics trigger inflammation, which contributes to a variety of diseases that together account for more than half of all deaths globally.
For now it’s impossible to prevent these reactions within the body, as human blood is about 50% water and cells are up to 80% water, Min noted.
"This challenges the reigning theory that plastic is inert," said Sherri 'Sam' Mason, a chemist at Gannon University who studies plastic pollution in freshwater.
"I think it highlights the need for truly biodegradable plastic, rather than what industry increasingly puts out into the marketplace," said Mason, who wasn’t involved in the new study.
Scientists are finding microplastics in nearly every part of the human body, including the brain, heart, ovaries and testicles.
Rapidly emerging research suggests the ingestion and inhalation of microplastics contribute to or outright trigger heart disease, dementia, Parkinson’s disease, impaired fertility and premature births, among other health problems.
Min and 11 colleagues found water molecules behave differently when coming into contact with microplastics, acting as a catalyst that spontaneously creates particles known as hydroxyl radicals, unstable molecules linked to aging and disease.
Two common types of plastic, polyethylene and polypropylene, used widely to make food containers and packaging, produced the most hydroxyl radicals detected by the researchers.
The finding suggests certain plastics could be reformulated or phased out of consumer products, Min said.
"Our bodies have natural defense mechanisms," said co-author Phoebe Stapleton, a Rutgers professor of pharmacology and toxicology. "But depending on other exposures we’ve had, our genetics and lifestyle choices, all of these (hydroxyl radicals) could build up to a point where we can’t handle them anymore."
More than 8 billion tons of plastic already pollute the Earth, and manufacturers are planning to triple production by 2060.
Craig Davis, senior director of plastics chemistry at the American Chemistry Council, said in an email that the study "offers a novel look at microplastics outside the body."
But, Davis said, "it does not establish whether the observed effects occur within the body’s complex biological systems or at actual human exposure levels to microplastics."
Min acknowledged the study’s limitations but said the findings should help direct future research.
He noted a group of Chinese researchers recently found that stirring plastic waste into hot water prompted similar chemical changes, raising the possibility of a less-toxic, more effective way to keep plastic litter out of the environment.
With files from Chicago Tribune