Report reveals elevated presence of plastic fragments in bottled water, surpassing earlier estimates by a whopping 100-fold.
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It's widely known that bottled water contains microplastics - minute fragments of harmful material as small as a bacterial cell. However, a recent study revealed that the problem is far more severe than previously thought. Researchers discovered that bottled water houses hundreds of thousands of even tinier pieces of microplastics.
A study published this week employed a unique method to analyze one-liter samples of bottled water for plastic granules, tracking down particles as short as 50 to 100 nanometers - roughly the width of a virus. Surprisingly, the research found almost a quarter of a million of these small particles per liter, which is approximately 10 to 100 times more than previously reported figures.
"We've opened up a whole new world," Wei Min, one of the study's authors and a chemistry professor at Columbia University, told Grist. The lack of a swift and efficient way to identify nanoplastics had long hindered research on their potential health and environmental impacts.
To conduct their analysis, researchers from Columbia and Rutgers universities filtered bottled water from various brands through an ultrafine membrane. They then shone two lasers at the membrane, calibrated to recognize the binding chemical bonds of the nanoplastic particles. Afterward, the researchers simply counted all the different types of plastic particles. They estimated that a typical one-liter water bottle contains around 240,000 of these particles.
Sherri Mason, an associate research professor at Penn State Erie who specializes in microplastics, praised the research technique as "groundbreaking."
"I was blown away," she told Grist. "It's just really good."
Furthermore, the researchers managed to distinguish between various types of nanoplastic. To their amazement, most of the particles were not polyethylene terephthalate, or PET - the material most water bottles are made of. Instead, the analysis revealed more particles of polyamide (a type of nylon) and polystyrene, which could suggest that these pollutants are infiltrating bottled water during the filling and purification process.
Polyamide made up the majority of the contamination by mass for two of the bottled water brands, while the third brand showed a higher level of PET.
With significant implications for human health, as nanoplastics are small enough to pass through the gastrointestinal tract and lungs, experts wonder about their potential harmful effects. After entering the bloodstream, nanoplastics can lodge in vital organs like the heart and brain. They can even cross the placenta to impact unborn babies. However, the long-term effects of nanoplastics on the human body remain unclear.
"We know we're getting exposed, but we don't know the toxicity of the exposures," said Beizhan Yan, another study co-author and an environmental chemist at Columbia University. He urged greater collaboration with toxicologists and public health researchers to better understand the risks.
The study's lead author, Wei, suggested that further research could explore other contamination sources, such as packaged food or wastewater from washing machines. The analysis could also improve techniques to detect even smaller particles.
"Fifty to 100 nanometers is our current detection limit, but that's not a hard stop," Wei said.
Meanwhile, Sherri Mason urged U.S. policymakers to take action by supporting the Break Free From Plastic Pollution Act - a federal bill that was reintroduced in Congress for the third time last October - or by endorsing plastic reduction as part of the United Nations' global plastics treaty.
"I don't want a plasticized world," she said. "We need to make it clear to our representatives that we need to chart a new path forward."
This article originally appeared in Grist at https://grist.org/science/bottled-water-nanoplastics-microplastics/. Grist is a nonprofit, independent media organization dedicated to exploring climate solutions and a just future. Learn more at Grist.org.
The groundbreaking study on microplastics in bottled water has implications for future health research, as nanoplastics can potentially pass through the human gastrointestinal tract and lungs, raising concerns about their long-term effects on human health. Furthermore, the analysis revealed that most of the particles found in bottled water were not the primary material used for water bottles, suggesting potential contamination during the filling and purification process, which could prompt researchers to explore other sources of contamination, such as packaged food or wastewater from washing machines.
