One study found that a bottle of water may contain 250,000 grains of plastic. Do you still dare to drink it?
Scientists have discovered a new plastic pollutant called nanoparticles, which is produced when microplastics break down further. Due to the limitations of analysis, it was previously impossible to know how many particles smaller than one micron (one-seventieth the width of a human hair) were in water.
However, a technique developed by Columbia University has shown that when nanoplastic particles are included, the actual amount of plastic debris floating in the water is 100 times greater than previously thought. Data shows that a standard litre of water contains 240,000 detectable plastic fragments, a number that could be as high as 370,000. Nine out of ten plastics are nanoplastics and are therefore smaller than one micron, or millionths of a meter.
A 2018 study found 325 nanoparticles per liter, but this estimate has since been revised upward, and now the addition of nanoplastics has exposed the true extent of ocean plastic pollution.
The scientists targeted seven common plastic polymers and fired lasers at them to detect the mass and quantity of nanoparticles in a certain volume of water.
PET (polyethylene terephthalate) is a common plastic that is made from the same material used to make plastic bottles. It is thought that small fragments of this material will fall off during use and subsequently enter the water supply as ketchup, sports drinks or soda bottles degrade.
Qian Naixin, the study's lead author and a graduate student in the chemistry department at Columbia University, said: "It's not entirely unexpected to find so many of these things.
The idea is that the smaller things are, the more they are. ”
However, the actual amount of plastic in the water may be much higher than that, as the team says the seven plastics make up only about 10% of all the plastics that have been found.
They warn that the true extent of water pollution could be millions of nanoparticles per liter.
Polyamide is a more common contaminant than PET, and the nylon type is often used as a filter to purify water before it enters the bottle. The main component of nanoparticle contamination may come from equipment that cleans it before consumption.
Scientists have found that microplastics still cause more water pollution by weight than smaller plastic blocks, but the sheer number of tiny pieces is a concern in itself.
There's a huge world of nanoplastics to be studied," said Min Wei, a Colombian biophysicist and co-author of the study, who invented the technology for analyzing plastic pollution.
It's not the size that matters, it's the quantity, because the smaller things are, the easier it is for them to get into us. ”
The health effects of plastic pollution in food and beverages are still relatively unknown and difficult to study, but we have found plastic in organ tissues, blood, and the tissues of the animals and plants we eat.
Smaller particles are more likely to infiltrate the intestines and blood vessels, which allows them to spread deeper into the body and various tissues, including the brain, where they can cause more damage.
The team now hopes to study tap water to understand how polluted the faucets are, and they also want to study the microplastics and nanoplastics that end up in wastewater when people wash their clothes, potentially releasing tens of millions of debris per wash.
The study was published in the journal Proceedings of the National Academy of Sciences.
I have to say that the research is very impressive. The work they've done for this is really profound ......I think it's groundbreaking," said Shirley Murray, director of sustainability at Penn State University, Belend, Erie, PA. Sherri "Sam" Mason said she was not involved in the study.
Mason said the new finding reinforces a long-standing recommendation by experts to drink tap water in glass or stainless steel containers to reduce exposure. She said the recommendation also applies to other foods and beverages in plastic packaging.
People don't think plastic comes off, but it does," she says, "almost like we keep shedding cells, plastic keeps shedding small pieces that come off, like when you open a plastic container for a store-bought salad or a cheese wrapped in plastic." ”
Mason is a co-author of a 2018 study that detected the presence of microplastics and nanoplastics for the first time in 93% of bottled water sold by 11 different brands in 9 countries.
In past studies, Mason has found that each liter of contaminated water contains an average of 10 plastic particles wider than a human hair, and 300 smaller particles. Five years ago, however, we had no way to analyze these tiny spots or find out if there were any more.
The latest research team found that the actual number of plastic debris in water from three popular brands sold in the U.S. is not 300 per liter, but 110,000 to 370,000, or even higher. (The authors declined to mention the bottled water brands they studied.) ）
However, the new technology is actually able to see millions of nanoparticles in water, which may be "inorganic nanoparticles, organic particles, and some other plastic particles that don't belong to the seven main types of plastics we studied," said co-author and environmental chemist Yan Beizhan. He is an associate research professor at the Lamont-Doherty Earth Observatory at Columbia University.
Jane Houlihan, director of the Bright Future Healthy Babies study, said the innovative new technologies proposed in the study open the door to further research to better understand the potential risks to human health. Bright Future is a coalition of nonprofits, scientists, and donors working to reduce health risks to infants. Exposed to neurotoxic chemicals, he was not involved in this study.
"They show that the risks posed by widespread human exposure to tiny plastic particles are largely unstudied," Hulihan said in an email. Infants and toddlers may be most at risk because their developing brains and bodies tend to be more susceptible to toxic exposure. ”
Experts say nanoplastics are the most worrying type of plastic pollution for human health. This is because tiny particles can invade individual cells and tissues in major organs, potentially interrupting cellular processes and depositing endocrine-disrupting chemicals such as bisphenols, phthalates, flame retardants, per- and polyfluorinated substances (PFAS), and heavy metals.
All of these chemicals are used to make plastics, so if plastic gets into our body, it will carry these chemicals. Since the body is hotter than the outside world, these chemicals will migrate out of the plastic and end up in our bodies," Mason explains.
"These chemicals can be carried to your liver, kidneys and brain, and even cross the placental border and end up in the unborn child," Mason said. ”
In the study of pregnant mice, researchers found plastic chemicals in the brain, heart, liver, kidneys and lungs of developing babies 24 hours after the pregnant mother ingested or inhaled plastic particles, according to study co-author Phoebe Stapleton, associate professor of pharmacology and chemistry. Toxicology at Rutgers University's Ernest Mario College of Pharmacy in Piscataway, New Jersey.
"Micro and nanoplastics are currently found in the human placenta," Stapleton said. They are found in human lung tissue. They are found in human feces;They are found in human blood. ”
In addition to the chemicals and toxic metals that plastics can carry, another relatively unstudied area is whether plastic polymers themselves are also harmful to the body.
The new frontier in plastics is understanding polymers – the plastic part of plastics," Mason said, "and our ability to understand the potential impact of polymers on human health is very limited because we can't detect that level." Now, with this new approach, we will be able to start doing so. ”
CNN reached out to the International Bottled Water Association, which represents the industry, to respond to the findings.
A spokesperson for the association told CNN via email: "This new method needs to be fully reviewed by the scientific community, and more research is needed to develop standardized methods for measuring and quantifying nanoplastics in our environment." ”
Currently, there is neither a standardized approach nor a scientific consensus on the potential health effects of nano- and microplastic particles. Therefore, reports about these particles in drinking water are nothing more than an unnecessary scare to consumers. ”
What happens once plastic polymers and endocrine-disrupting chemicals enter the body's cells?Will the invaders stay, wreak havoc by disrupting or disrupting cellular processes, or will the body succeed in driving them out?
"We know that these particles are going into the body, and we know that a larger percentage of smaller nanoparticles are getting into the cell, but we don't know exactly where they're going in the cell or what they're doing," Stapleton said. We don't know if or how they will come back again. ”
Houlihan of Healthy Babies of Bright Futures said there are steps people can take to reduce their exposure to plastic while science explores these and other issues.
We can avoid eating food and drinks in plastic containers. We can wear clothes made of natural fabrics and buy consumer goods made from natural materials," says Houlihan, "We can simply take stock of plastic in our daily lives and look for alternatives where feasible." ”