Microplastics can be a risk factor for cardiovascular disease

Add another likely culprit to the long list of known cardiovascular risk factors, including red meat, butter, smoking and stress: microplastics.

In a study released Wednesday in the New England Journal of Medicine, an international team of physicians and researchers showed that surgical patients with a build-up of micro- and nanoplastics in their arterial plaque had a 2.1 times greater risk of a non-fatal heart attack, a non-fatal stroke or death from any disease. cause in the three years after surgery than those who did not.

It is the first study to show that these ubiquitous and pernicious fossil fuel-based particles have a direct effect on human health, says study co-author Antonio Ceriello, head of the diabetes department at IRCCS MultiMedica, a research hospital in Milan .

And it should serve as a warning to all people, governments and businesses that plastic is not only a nuisance and harmful to the environment, but also harmful to human health, he said.

As government officials, negotiators, environmentalists and business representatives prepare to meet in Ottawa next month to discuss a global ban on plastic pollution, many hope this study will tip the balance toward enacting real and tangible regulations .

“This is a start… where people are starting to realize that plastic isn't just harmful to whales and sea turtles. It's not just litter on a beach in a faraway country. It's in them and it can cause damage. I think it's going to change the narrative,” said Dr. Philip Landrigan, director of the Program for Global Public Health and the Common Good at Boston College.

He compared awareness of the plastic crisis to climate change – where people understood it in an abstract, theoretical way until forest fires burned down their homes, persistent heat waves killed their crops and floods devastated their communities.

“To my knowledge, this is the first report linking microplastics to human disease,” said Landrigan, who was not involved in the study but wrote an accompanying essay urging the global community to implement a “mandatory global plastic production cap.”

Matt Seaholm, president and CEO of the Plastics Industry Assn., suggested more research needs to be done.

“We encourage lawmakers to evaluate where those particles come from before using any type of microplastics or nanoplastics arguments to justify or pass laws, because every study has shown that they do not come from packaging or single-use items,” he said. .

Research has shown that the two biggest contributors to microplastics in the environment are car tires and synthetic clothing. However, as the plastics industry expands and the number of single-use plastic items grows, so does their contribution to environmental contamination and pollution. All around 151 million tons of single-use plastic were produced
from fossil fuels in 2021. This number is expected to increase by another 19 million tons by 2027.

The arterial plaque study was conducted by a team of 40 scientists – including surgeons, engineers, statisticians and pathologists – from more than a dozen institutions, including Harvard Medical School, Brigham and Women's Hospital in Boston and Case Western Reserve School of Medicine in Cleveland. .

The 257 patients who completed the study all had asymptomatic extracranial high-grade internal carotid artery stenosis – in other words, their carotid arteries were blocked with plaque. The patients underwent carotid endarterectomies, a procedure that opens the artery and removes the plaque. Patients who had previously had heart failure, valve defects, cancer, or other causes of hypertension were disqualified.

The researchers then examined the plaque and found micro- and nanoparticles of polyethylene in 150 of the patients. Thirty patients had polyvinyl chloride particles in their plaque. Electron microscopy images showed visible, jagged 'foreign bodies' along with the biological plaque in these patients.

Polyethylene, or PET, is the plastic used to make soda and water bottles. Polyvinyl chloride, or PVC, is the plastic used in water pipes, packaging, medical equipment, toothbrushes, children's toys and window frames, to name a few.

The two patient populations were approximately the same in terms of age, gender, weight, smoking status, geographic location, blood pressure, and heart rate.

The only notable difference, the authors noted, was the two groups' susceptibility to heart disease in the months after surgery – an indication that the presence of microplastics may have played a role. Indeed, indicators of inflammation were higher in the group exposed to plastic. Non-fatal heart attack, non-fatal stroke or death from any cause occurred in eight of 107 patients who had no microplastics in their plaque and in 30 of 150 patients with microplastics.

On Wednesday, July 26, 2023, trash lies on the East Fork of the San Gabriel River in the San Gabriel Mountains National Monument in the Angeles National Forest.

(Allen J. Schaben/Los Angeles Times)

The authors emphasized that they could only demonstrate correlation, not causation. Additional research would be needed to establish a clear connection.

Study co-author Leonardo Trasande, a pediatrician and public policy expert at New York University's Grossman School of Medicine and Wagner School of Public Service, said it's just as possible that chemicals are free-riding on the particles – such as bisphenol A, phthalates and/or other plasticizers and additives – could be the culprits. The article also notes that laboratory contamination and patient behavior unknown to the researchers could also influence their results.

“I can't tell you it's the microplastics, and I can't tell you it's the chemicals. I couldn't tell you because no study has measured both and they both coexist,” he said. “The fact is that plastics are terrible for human health and are expensive.”

He pointed to a recent study he authored that showed the disease burden from these chemicals costs the U.S. health care system about $250 billion a year.

Ceriello and his co-authors noted dozens of animal studies showing harmful effects of microplastics. He also said the authors were still unclear about how patients were exposed, whether through inhalation or ingestion.

Recent studies have found micro- and nanoplastics in water contained in plastic bottles, as well as in dust.

“This is very solid and should be taken very seriously at the highest levels of government,” said Judith Enck, director of Beyond Plastics and former regional director at the U.S. Environmental Protection Agency. “This is consistent with other studies that have found microplastics in various organs, human blood, placenta and breast milk, so this is not too surprising, but still astonishing.”

Plastic has been found everywhere scientists have looked: from the deepest ocean trenches to the highest mountain peaks. Petroleum-based plastics are not biodegradable. Over time, they break down into smaller and smaller pieces – known as microplastics, microfibers and nanoplastics – and have been found in household dust, drinking water and human tissue and blood.

“Cardiologists need to educate their patients to avoid plastic packaging – which is very difficult to do,” Enck said.

Tracey Woodruff, director of UC San Francisco's Reproductive Health and Environment Program in the Department of Obstetrics, Gynecology and Reproductive Sciences, said clinicians and clinicians need to start talking to their patients about the harms of plastic. She wrote an essay which looked at the harmful effects of endocrine disruptors in the same edition as the heart study.

She said doctors' advice to eat organic, unprocessed foods already reduces plastic exposure. But more is needed, especially in the medical fields of reproduction, obstetrics and pediatrics, she said, where evidence of harm from plastic chemicals and endocrine disruptors is well established.

The mounting evidence, she said, is becoming “hard to ignore.”