It’s been more than five decades since Dustin Hoffman’s character in “The Graduate” was offered a kernel of wisdom about the path to prosperity.
“Plastics,” Mr. McGuire, the stuck-up corporate executive offering the advice, told him. “There is a great future in plastics.”
Plastics have indeed changed the game for humanity, and the vast array of cheap, durable plastic items, from food containers and PVC pipes to polyester clothing and disposable medical products, have undeniably improved life.
The problem, as almost everyone knows, is that plastics last forever and very little of it is recycled. The UN has estimated that most of the 400 million metric tons produced annually – a doubling of output since 2000 – will remain on Earth in some form as it is broken down into small specks by sunlight, wind and the sea.
About 20 years ago, Richard Thompson, a marine biologist, first discovered an alarming accumulation of small plastic particles in ocean habitats and coined the word “microplastics.” Since then, scientists have found these fragments everywhere, from remote mountaintops and the Arctic to the ocean floor.
In the decade that followed, scientists began to discover microplastics embedded in a wide range of living creatures, including the seafood we eat. More recently, microplastics have been found inside the human body: in our lungs, in our blood, in our feces and in breast milk.
In 2021, Italian researchers detected microplastics in the human placenta for the first time.
The question scientists are asking with increasing urgency is whether these synthetic, foreign bodies pose a threat to human health.
“We know microplastics are everywhere, we know they’re harmful to marine life and our fisheries, but the research side of how they affect people is still coming,” said Imari Walker-Franklin, an environmental engineer and chemistry researcher. at RTI International. who studies microplastics.
“Plastic People,” a new documentary directed by Ben Addelman and Ziya Tong, examines the emerging science of microplastics and comes to an alarming conclusion: The potential health risks associated with plastic pollution are becoming hard to ignore.
The film, which premieres Saturday at the SXSW Film Festival in Austin, Texas, follows the work of microplastics researchers in half a dozen countries, including a pair of Turkish scientists who said they recently discovered microplastics inside the human brain. Some of the particles were found deep within the tissue of cancerous brain tumors.
“The revelation that the human body is full of microplastics is recent, and I think the implications will become one of the most dominant health and environmental stories of our time,” said Rick Smith, president of the Canadian Climate Institute and one of the executive producers of the film. “It doesn’t matter if you’re rich or poor, there’s no protection against this kind of new pollution.”
Microplastics, fragments less than The five millimeters in size that can usually be seen with the naked eye are not to be confused with nanoplastics, which are smaller than a speck of dust and are often the unintended byproduct of plastics production. Research into the potential health effects of nanoplastics is still in its infancy, at least compared to studies of microplastics, a field that has been expanding rapidly in recent years.
Scientific evidence on the effects of microplastics on humans is limited, at least in the peer-reviewed literature. A 2022 study in the journal Environmental Science & Technology found that patients with inflammatory bowel disease had a significantly higher amount of microplastics in their stool than those without the disease. A small University of Hawaii study published last November documented the increasing presence of microplastics in the placentas of new mothers.
And a paper published Thursday in the New England Journal of Medicine reported that people who had microplastics in their cardiovascular systems were at increased risk for complications from heart attacks and strokes.
The researchers found that the microplastics were embedded in the fatty plaque that adheres to the walls of blood vessels and that patients with plastic plaque were 4.5 times more likely to have a heart attack, stroke or death compared to those whose plaque was free microplastics. The study included 312 people who had undergone surgery to remove carotid plaque in the neck. The researchers followed them for almost three years.
Dr. Giuseppe Paolisso, an author of the study, said it appeared that microplastics, along with nanoplastics, made these fatty plaque droplets more fragile, increasing the risk of them breaking away from the artery wall, blocking blood flow in a smaller vessel. and cause a heart attack or stroke.
“This is the first evidence that microplastic pollution in the blood is associated with a disease,” said Dr. Paolisso, professor of internal medicine at the Luigi Vanvitelli University of Campania in Caserta, Italy. More research is needed to confirm the findings, he added.
There are a number of theories about how microplastics affect the body. They include the potential for inflammation caused by a foreign body lodged in human tissue and the toxic compounds that make up many plastics, many of which are known to harm human health.
Nienke Vrisekoop, a microplastics researcher at Utrecht University Medical Center in the Netherlands, said she found that immune cells that come into contact with microplastics die three times faster than those that don’t. He said the polystyrene commonly used to make packaging materials was particularly toxic to the immune cells that consumed it.
Research conducted by another Dutch researcher, Barbro Melgert, found that microplastics inhibited the growth of lung structures grown in her laboratory. Professor Melgert, a respiratory immunologist at the University of Groningen, said nylon appeared to be more damaging to lung structures. Polyvinyl chloride, or PVC, he found, was the least toxic of the plastics he tested.
Professor Melgert is still trying to understand how microplastics affect living cells, but she suspects the damage could be related to any number of chemicals that can leach from plastics into the human body.
While aware that the study results do not definitively prove harm to humans, nor quantify the risks, previous research in nylon factory workers showed extensive lung damage among those exposed to large amounts of nylon particles.
Foreign particles such as asbestos, coal dust or cigarette smoke often prove problematic for human health, he noted. “If the particles are organic and easily digestible, at least your body can eventually break them down and get rid of them,” Professor Melgert said. “Plastic is different. It can just stay in the lung.”
The same can probably be said for the microplastics that find their way into the brain. The discovery, arguably the most important revelation of the new film, was made by two Turkish researchers, Sedat Gündoğdu, a biologist, and Emrah Çeltikçi, a neurosurgeon.
Dr. Gündoğdu, a researcher at Cukurova University, has been studying microplastic pollution since 2016. Over the years, he has collaborated on dozens of peer-reviewed studies documenting microplastics in fisheries, soil, table salt and IV fluid bags, and his alarm has grown with every new discovery.
It was only a matter of time, he said, before researchers discovered microplastics in the human brain. “It’s scary but not surprising,” he said.
Of the 15 samples tested so far, six plastic particles have been identified in tissue from two tumor patients, Dr. Gundogdu said. It was not clear how the fragments entered the brain, but he said that given the documented presence of microplastics in the blood, they likely arrived via vessels feeding the tumors.
Despite the sense of urgency and doom that “Plastic People” conveys, Ms. Tong, co-director and former host of the Discovery Channel’s science show “Daily Planet,” hopes the film can inspire change, like ” Silent Spring, the 1962 book that documented the dangers of agricultural pesticides and helped ban DDT, did.
At the individual level, that means encouraging consumers to reduce their reliance on single-use plastics, which make up 40 percent of global plastic production, he said.
But that also means convincing political leaders to take regulatory action. Right now, Ms. Tong has her sights set on a UN gathering next month in Ottawa, where representatives from 175 countries will continue negotiations on a proposed treaty to curb the explosive growth in plastic pollution. The talks have been bogged down at times by industry opposition.
“We don’t need some remarkable new invention to tackle the problem,” Ms Tong said. “We just need to use less plastic.”
