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[00:00.04]A new study examines possible harm

[00:04.00]caused by microscopic pieces of plastic

[00:08.16]that end up inside people's bodies.

[00:11.56]These materials – known as microplastics

[00:16.32]and nanoplastics – can enter the body

[00:20.16]through the air or in food or drinks.

[00:24.04]Tiny plastic pieces have received

[00:27.68]widespread attention in the media.

[00:30.60]But so far, very little research has been done

[00:35.16]on how the substances affect human heart health.

[00:40.12]One new study suggests the buildup

[00:43.68]of such plastics inside the body

[00:46.76]can increase the risk of a stroke,

[00:49.52]heart attack or death.

[00:51.96]But the researchers noted the evidence presented

[00:56.20]cannot prove a direct link

[00:58.88]between tiny plastic materials

[01:01.92]and heart problems.

[01:04.36]The study involved 257 people

[01:09.36]who had medical operations

[01:12.04]to clear blocked blood vessels in their necks.

[01:16.20]Italian researchers examined the fatty buildup

[01:20.68]the doctors removed from the carotid arteries,

[01:24.80]which supply blood and oxygen to the brain.

[01:29.32]Using two methods, they found evidence of plastics

[01:34.40]– mostly nanoplastics that cannot be seen

[01:38.12]– in the artery plaque of 150 patients.

[01:42.64]No evidence of plastics was seen in 107 patients.

[01:49.20]The team followed these people for three years.

[01:53.80]During that time, 30 individuals,

[01:57.08]or 20 percent of the group with plastics,

[02:00.76]had a heart attack, stroke, or died from any cause.

[02:05.68]These rates dropped to about eight percent

[02:09.56]among those with no evidence of plastics.

[02:13.20]Research results were recently published

[02:17.08]in a study in the New England Journal of Medicine.

[02:21.08]The researchers also found more evidence of inflammation

[02:26.60]in individuals with tiny plastic bits in their blood.

[02:31.16]Inflammation is the body's reaction to injury

[02:35.76]and is thought to raise the risk of heart attacks and strokes.

[02:40.56]The researchers admitted their study was very small.

[02:45.92]For example, it only looked at people with narrowed arteries

[02:51.24]who were already at risk for heart attacks and stroke.

[02:55.60]And the patients with the plastics had more heart disease,

[03:00.96]diabetes and high cholesterol

[03:03.92]than those without plastics.

[03:06.60]They were also more likely to be men

[03:09.76]and more likely to be smokers.

[03:12.60]Both of those groups generally

[03:15.52]have higher rates of heart disease.

[03:18.20]The researchers tried to account

[03:21.52]for these risk differences.

[03:24.12]But they noted they may have missed

[03:27.24]some important elements

[03:29.16]that could change the results.

[03:31.96]The team said because of these ongoing questions,

[03:36.00]this kind of study cannot prove the plastics

[03:40.00]caused the health problems.

[03:42.60]Steve Nissen is a heart expert

[03:46.28]at the Cleveland Clinic in the state of Ohio

[03:49.60]who was not part of the study.

[03:52.36]He told the Associated Press

[03:55.68]he thinks the team's estimate

[03:58.24]that the risk of heart attack, stroke or death

[04:02.00]was four times greater seems too high.

[04:06.12]"It would mean that these microplastics

[04:09.88]are the most important cause

[04:11.72]of coronary heart disease yet discovered.

[04:15.88]And I just don't think that's likely to be right," Nissen said.

[04:21.76]Philip Landrigan of Boston College University

[04:26.44]told the AP that more research is needed on the issue.

[04:31.88]Landrigan, who wrote about the study in the Journal,

[04:36.12]said it is the first one suggesting

[04:39.24]a connection between microplastics

[04:42.08]and nanoplastics with disease in humans.

[04:46.56]Other scientists have found plastic bits in the lungs,

[04:51.76]liver, blood, placenta and breast milk.

[04:56.36]"It does not prove cause and effect,

[05:00.00]but it suggests cause and effect," Landrigan said.

[05:05.08]"And it needs urgently to be either replicated

[05:09.44]or disproven by other studies

[05:12.44]done by other investigators in other populations."

[05:17.40]The Cleveland Clinic's Nissen added about the study,

[05:22.00]"It's a wake-up call that perhaps we need

[05:25.28]to take the problem of microplastics more seriously.

[05:30.12]As a cause for heart disease? Not proven.

[05:34.48]As a potential cause? Yes, maybe," Nissen said.

[05:40.00]I'm Bryan Lynn.

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Words in This Story

artery – n. a tube in the body that carries blood from your heart

inflammation – n. the swelling of tissue in the body

cholesterol – n. a kind of substance in the body that is linked to heart disease

contaminate – v. to make something dirty or poisonous

placenta –n. a temporary organ that forms in the womb and that provide blood and nutrition to the fetus through the umbilical cord

replicate – v. to make or do something again in exactly the same way

potential – adj. possible