Are Tiny Plastic Particles in Our Bodies Harmful?
2024-03-16
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1A new study examines possible harm caused by microscopic pieces of plastic that end up inside people's bodies.
2These materials - known as microplastics and nanoplastics - can enter the body through the air or in food or drinks.
3Tiny plastic pieces have received widespread attention in the media.
4But so far, very little research has been done on how the substances affect human heart health.
5One new study suggests the buildup of such plastics inside the body can increase the risk of a stroke, heart attack or death.
6But the researchers noted the evidence presented cannot prove a direct link between tiny plastic materials and heart problems.
7The study involved 257 people who had medical operations to clear blocked blood vessels in their necks.
8Italian researchers examined the fatty buildup the doctors removed from the carotid arteries, which supply blood and oxygen to the brain.
9Using two methods, they found evidence of plastics - mostly nanoplastics that cannot be seen - in the artery plaque of 150 patients.
10No evidence of plastics was seen in 107 patients.
11The team followed these people for three years.
12During that time, 30 individuals, or 20 percent of the group with plastics, had a heart attack, stroke, or died from any cause.
13These rates dropped to about eight percent among those with no evidence of plastics.
14Research results were recently published in a study in the New England Journal of Medicine.
15The researchers also found more evidence of inflammation in individuals with tiny plastic bits in their blood.
16Inflammation is the body's reaction to injury and is thought to raise the risk of heart attacks and strokes.
17The researchers admitted their study was very small.
18For example, it only looked at people with narrowed arteries who were already at risk for heart attacks and stroke.
19And the patients with the plastics had more heart disease, diabetes and high cholesterol than those without plastics.
20They were also more likely to be men and more likely to be smokers.
21Both of those groups generally have higher rates of heart disease.
22The researchers tried to account for these risk differences.
23But they noted they may have missed some important elements that could change the results.
24The team said because of these ongoing questions, this kind of study cannot prove the plastics caused the health problems.
25Steve Nissen is a heart expert at the Cleveland Clinic in the state of Ohio who was not part of the study.
26He 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.
27"It would mean that these microplastics are the most important cause of coronary heart disease yet discovered.
28And I just don't think that's likely to be right," Nissen said.
29Philip Landrigan of Boston College University told the AP that more research is needed on the issue.
30Landrigan, who wrote about the study in the Journal, said it is the first one suggesting a connection between microplastics and nanoplastics with disease in humans.
31Other scientists have found plastic bits in the lungs, liver, blood, placenta and breast milk.
32"It does not prove cause and effect, but it suggests cause and effect," Landrigan said.
33"And it needs urgently to be either replicated or disproven by other studies done by other investigators in other populations."
34The Cleveland Clinic's Nissen added about the study, "It's a wake-up call that perhaps we need to take the problem of microplastics more seriously. As a cause for heart disease? Not proven. As a potential cause? Yes, maybe," Nissen said.
35I'm Bryan Lynn.
1A new study examines possible harm caused by microscopic pieces of plastic that end up inside people's bodies. 2These materials - known as microplastics and nanoplastics - can enter the body through the air or in food or drinks. 3Tiny plastic pieces have received widespread attention in the media. But so far, very little research has been done on how the substances affect human heart health. 4One 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. 5What did the study find? 6The study involved 257 people who had medical operations to clear blocked blood vessels in their necks. Italian researchers examined the fatty buildup the doctors removed from the carotid arteries, which supply blood and oxygen to the brain. 7Using two methods, they found evidence of plastics - mostly nanoplastics that cannot be seen - in the artery plaque of 150 patients. No evidence of plastics was seen in 107 patients. 8The 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. 9Research results were recently published in a study in the New England Journal of Medicine. 10The researchers also found more evidence of inflammation in individuals with tiny plastic bits in their blood. Inflammation is the body's reaction to injury and is thought to raise the risk of heart attacks and strokes. 11What are the problems with the study? 12The 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. 13And the patients with the plastics had more heart disease, diabetes and high cholesterol than those without plastics. They were also more likely to be men and more likely to be smokers. Both of those groups generally have higher rates of heart disease. 14The researchers tried to account for these risk differences. But they noted they may have missed some important elements that could change the results. The team said because of these ongoing questions, this kind of study cannot prove the plastics caused the health problems. 15Steve 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. 16"It would mean that these microplastics are the most important cause of coronary heart disease yet discovered. And I just don't think that's likely to be right," Nissen said. 17What is next for the researchers? 18Philip Landrigan of Boston College University told the AP that more research is needed on the issue. Landrigan, who wrote about the study in the Journal, said it is the first one suggesting a connection between microplastics and nanoplastics with disease in humans. Other scientists have found plastic bits in the lungs, liver, blood, placenta and breast milk. 19"It does not prove cause and effect, but it suggests cause and effect," Landrigan said. "And it needs urgently to be either replicated or disproven by other studies done by other investigators in other populations." 20The Cleveland Clinic's Nissen added about the study, "It's a wake-up call that perhaps we need to take the problem of microplastics more seriously. As a cause for heart disease? Not proven. As a potential cause? Yes, maybe," Nissen said. 21I'm Bryan Lynn. 22The Associated Press reported this story. Bryan Lynn adapted the report for VOA Learning English. 23_____________________________________________ 24Words in This Story 25artery - n. a tube in the body that carries blood from your heart 26inflammation - n. the swelling of tissue in the body 27cholesterol - n. a kind of substance in the body that is linked to heart disease 28contaminate - v. to make something dirty or poisonous 29placenta -n. a temporary organ that forms in the womb and that provide blood and nutrition to the fetus through the umbilical cord 30replicate - v. to make or do something again in exactly the same way 31potential - adj. possible