A new study examines possible harm caused by microscopic pieces of plastic that end up inside people's bodies. These materials -known as microplastics and nanoplastics - can enter the body through the air or in food or drinks.
One new study suggests the buildup of such plastics inside the body can increase the risk of a stroke, heart attack or death. But the researchers noted the evidence presented cannot prove a direct link between tiny plastic materials and heart problems.
The study involved 257 people who had medical operations to clear blocked blood vessels （血管） in their necks. Italian researchers examined the fatty buildup the doctors removed from the carotid arteries, which supply blood and oxygen to the brain. Using two methods, they found evidence of plastics-mostly nanoplastics that cannot be seen-in the artery plaque（动脉斑块）of 150 patients. No evidence of plastics was seen in 107 patients.
The team followed these people for three years. During that time, 30 individuals, or 20 percent of the group with plastics, had a heart attack, stroke, or died from any cause. These rates dropped to about eight percent among those with no evidence of plastics. Research results were recently published in a study in the New England Journal of Medicine.
The researchers admitted their study was very small. For example, it only looked at people with narrowed arteries who were already at risk for heart attacks and stroke.
Steve Nissen is a heart expert at the Cleveland Clinic in the state of Ohio who was not part of the study. He told the Associated Press he thinks the team's estimate that the risk of heart attack, stroke or death was four times greater seems too high. "It would mean that these microplastics are the most important cause of coronary heart disease （冠心病） yet discovered. And I just don't think that's likely to be right," Nissen said. "Maybe, it's just a wake-up call that perhaps we need to take the problem of microplastics more seriously." Nissen added.
