Inhaling plastic dramatically raises a person’s risk of heart attack, stroke, and early death, according to Italian researchers.
Through specialised tests, the researchers found harmful microplastics mixed with chlorine in the blocked arteries of over half the people in their study (150 out of 312 people).
These people were 4.5 times more likely to have a heart attack, stroke, or die in the next three years due to the microplastics disrupting their body’s fat processing.
Professor Philip Landrigan said their arteries contained around 21.7 micrograms of the most common plastic (polyethylene) and 5.2 micrograms of the third most common plastic (polyvinyl chloride), most likely through eating and breathing.
“Polyethylene and polyvinyl chloride, in their various forms, are used in a wide range of applications, including the production of food and cosmetics containers and water pipes,” he said, cautioning particles in pipes enter drinking water.
“In a form bound to fine, inhalable particulate matter... transported long distances by wind.”
He said the smaller than 200-nanometre particles become stuck between artery cells after passing through barriers like the gut.
The World Health Organisation (WHO) states that particles larger than 150 micrometres can’t enter the bloodstream or blood vessels.
Other human studies have found particles up to 30 micrometres in size in the liver, up to 10 micrometres in the placentas, up to 88 micrometres in the lungs, up to 12 to 15 micrometres in breast milk and urine, and over 700 nanometres in whole blood.
One micrometre is 1,000 nanometres.
Mr. Landrigan noted that discovering microplastics in the human body was groundbreaking and raised many pressing issues that demand immediate attention.
He pointed to, for example, the dangerous additives in plastic particles, such as chlorine, which are highly carcinogenic and pose a severe threat to human health.
He asked, “What organs in addition to the heart may be at risk? How can we reduce exposure?”
“The first step is to recognise that the low cost and convenience of plastics are deceptive and that, in fact, they mask great harms,” he said.
He encouraged reducing plastic use, particularly unnecessary single-use items, and emphasised the importance of monitoring and minimising plastic usage personally and in workplaces.
People aged 18 to 75 with severe blockages in their neck arteries who were going to have surgery to clear them participated in the study.
Those with heart failure, certain heart problems, cancer, or other issues were not included.
Limited Understanding of Microplastics: WHO
WHO recently investigated microplastics in drinking water and published a report (pdf) on their associated health risks following an increase in microplastic presence in the environment.However, it noted information about how harmful microplastics were when breathed in or eaten was “limited.”
“The components of microplastic that represent the greatest risk to human health are poorly understood, although a contribution of microplastics cannot be excluded,” a WHO spokesperson stated.
“Information is required on the effects of particle size, shape, polymer composition, and other factors representative of environmentally relevant microplastics.”
The spokesperson noted microplastics could also have adverse effects like other small, solid particles acting similarly.
Still, they acknowledged that the public was becoming more aware of plastics, with a general consensus that they should not be in the environment and that steps were needed to be taken to reduce exposure.
“This should include better management of plastics throughout their product life-cycle and reducing the use of plastics, when possible, to move towards a more sustainable plastics economy.”
