Researchers found micro- and nanoplastics in 84% of heart attack patients studied, compared with lower rates in other groups.
The study identified a link between plastic particles in the blood, smoking, and long-term exposure to air pollution.
The findings show an association — not proof that plastic particles cause heart attacks — and more research is needed.
Microplastics and even smaller nanoplastics have been detected in everything from drinking water to human organs, but scientists are still working to understand what those particles might mean for our health. Now, a new study suggests they may also be connected to heart disease.
Researchers found that people who experienced a heart attack were much more likely to have micro- and nanoplastics in their blood than people with chronic heart disease or those with normal coronary arteries.
The findings were presented in the European Heart Journal and add to a growing body of research examining whether environmental pollution could play a role in cardiovascular health. However, the researchers emphasize that the study found an association, not evidence that plastic particles directly cause heart attacks.
“Micro and nanoplastics are tiny plastic particles that are found virtually everywhere in the environment, including the air we breathe, the water we drink, and many foods we consume,” researcher Dr Pasquale Paolisso said in a news release.
“In recent years, scientists have begun to detect these particles in human tissues and organs, raising concerns about their potential health effects.However, very little was known about whether these particles are present in the coronary circulation – the blood flowing through the arteries that supply the heart – or whether environmental exposures such as smoking and air pollution might influence their presence.”
How the researchers studied the connection
The study included 61 adults undergoing coronary angiography, a procedure that allows doctors to examine the heart's blood vessels. Participants were divided into three groups: patients who had suffered a heart attack, those with chronic ischemic heart disease, and people whose coronary arteries appeared normal.
Blood samples were collected during the procedure and analyzed for micro- and nanoplastics. Researchers also gathered information about each participant's smoking status and estimated their long-term exposure to fine particulate air pollution over the previous two years.
The goal was to see whether environmental factors might be linked to the presence of plastic particles in the bloodstream.
What the findings could mean for consumers
Among heart attack patients, micro- and nanoplastics were detected in 84% of blood samples, compared with 40% of patients with chronic ischemic heart disease and 32% of those with normal coronary arteries.
The heart attack group also had a greater variety of plastic types in their blood, with polyethylene — the plastic commonly used in packaging and consumer products — being the most frequently detected.
The researchers also found that people with higher long-term exposure to air pollution were more likely to have plastic particles in their blood, and smokers were six times more likely to test positive than non-smokers. Every participant who both smoked and had higher air pollution exposure had detectable plastics in their blood.
Even so, the researchers caution that these findings do not establish cause and effect. Instead, they suggest that environmental exposures, including plastic pollution, deserve more attention as scientists continue investigating factors that may influence heart health.
“These findings do not prove that microplastics cause heart attacks, but they reveal a strong association between environmental exposures, microplastics in the blood and cardiovascular disease,” researcher Emanuele Barbato said in the release.
“Our findings suggest that smoking might make it easier for micro and nanoplastics to enter the blood stream via the lungs. The results highlight the need to consider microplastic pollution as part of the broader environmental determinants of health. Policies that reduce air pollution, tobacco exposure, and environmental plastic contamination could have benefits that extend beyond environmental protection and potentially improve cardiovascular health.”