Study Finds Small Plastic Pieces in Bottled Water
2024-01-18
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1The average liter of bottled water has nearly a quarter million invisible pieces of very small plastic known as nanoplastics, a recent study says.
2Researchers found the nanoplastics with a microscope using dual lasers.
3Scientists long figured there were lots of these very small plastic pieces.
4But until researchers at Columbia and Rutgers universities did their calculations, they never knew how many or what kind.
5Looking at five samples each of three common bottled water brands, researchers found particle levels ranged from 110,000 to 400,000 per liter.
6The average was around 240,000, the study said.
7The research appeared recently in the publication Proceedings of the National Academy of Sciences.
8Nanoparticles are particles that are less than a micron in size.
9In comparison, a human hair is about 83 microns wide.
10Previous studies have looked at slightly bigger microplastics that range from 5 millimeters, which could be seen by human eyes, to one micron.
11About 10 to 100 times more nanoplastics than microplastics were discovered in bottled water, the study found.
12Much of the plastic seems to be coming from the bottle and the filtration system to clean the water itself, said the study's lead writer Naixin Qian of Columbia University.
13She would not name the three brands because researchers want more samples and they want to study more brands.
14Still, she said they were common and bought at a Walmart, a popular store in the U.S.
15Researchers still cannot answer the big question: Are those nanoplastic pieces harmful to health?
16"That's currently under review. We don't know if it's dangerous or how dangerous," said study co-writer Phoebe Stapleton of Rutgers University.
17"We do know that they are getting into the tissues (of mammals, including people) ... and the current research is looking at what they're doing in the cells."
18The International Bottled Water Association said in a statement: "There currently is both a lack of standardized (measuring) methods and no scientific" agreement on the possible health effects of nano- and microplastic particles.
19The statement added, "Therefore, media reports about these particles in drinking water do nothing more than unnecessarily scare consumers."
20The American Chemistry Council, which represents plastics manufacturers, declined to immediately comment.
21The Associated Press spoke with four co-writers of the study.
22All of them said they would cut back on their bottled water use.
23Columbia chemist Wei Min said he has reduced his bottled water use by half.
24Stapleton said she now depends more on filtered water at home in New Jersey.
25But study co-author Beizhan Yan, a Columbia environmental chemist who increased his tap water usage, pointed out that filters themselves can be a problem by introducing plastics.
26"There's just no win," Stapleton said.
27Outside experts, who praised the study, agreed that there is a general unease about the risks of fine plastic particles.
28Still, it is too early to say anything certain about the risks.
29"The danger of the plastics themselves is still an unanswered question.
30For me, the additives are the most concerning," said Jason Somarelli of Duke University in North Carolina.
31Somarelli was not part of the research.
32He added, "We and others have shown that these nanoplastics can be internalized into cells, and we know that nanoplastics carry all kinds of chemical additives that could cause cell stress, DNA damage and change metabolism or cell function."
33Somarelli said his own research has found more than 100 "known cancer-causing chemicals in these plastics."
34About 15 years ago, Min invented dual laser microscope technology that identifies specific compounds by their chemical properties and how they respond when exposed to lasers.
35Yan and Qian talked to him about using that technique to find and identify plastics that had been too small for researchers using established methods.
36Kara Lavender Law of the Sea Education Association said "the work can be an important advance in the detection of nanoplastics,"
37but she said she'd like to see other chemists use the technique and get the same results.
38Yan said he is starting to study water supplies in the U.S. cities of Boston, St. Louis, Los Angeles and elsewhere to see how much plastics are in their tap water.
39Previous studies looking for microplastics and some early tests suggest there may be less nanoplastic in tap water than in bottled water.
40Even with unknowns about human health, Yan said he does have one suggestion: Use reusable bottles instead of single-use plastics.
41I'm John Russell.
42And I'm Ashley Thompson.
1The average liter of bottled water has nearly a quarter million invisible pieces of very small plastic known as nanoplastics, a recent study says. 2Researchers found the nanoplastics with a microscope using dual lasers. 3Scientists long figured there were lots of these very small plastic pieces. But until researchers at Columbia and Rutgers universities did their calculations, they never knew how many or what kind. 4Looking at five samples each of three common bottled water brands, researchers found particle levels ranged from 110,000 to 400,000 per liter. The average was around 240,000, the study said. The research appeared recently in the publication Proceedings of the National Academy of Sciences. 5Nanoparticles are particles that are less than a micron in size. In comparison, a human hair is about 83 microns wide. 6Previous studies have looked at slightly bigger microplastics that range from 5 millimeters, which could be seen by human eyes, to one micron. About 10 to 100 times more nanoplastics than microplastics were discovered in bottled water, the study found. 7Much of the plastic seems to be coming from the bottle and the filtration system to clean the water itself, said the study's lead writer Naixin Qian of Columbia University. 8She would not name the three brands because researchers want more samples and they want to study more brands. Still, she said they were common and bought at a Walmart, a popular store in the U.S. 9Researchers still cannot answer the big question: Are those nanoplastic pieces harmful to health? 10"That's currently under review. We don't know if it's dangerous or how dangerous," said study co-writer Phoebe Stapleton of Rutgers University. "We do know that they are getting into the tissues (of mammals, including people) ... and the current research is looking at what they're doing in the cells." 11The International Bottled Water Association said in a statement: "There currently is both a lack of standardized (measuring) methods and no scientific" agreement on the possible health effects of nano- and microplastic particles. The statement added, "Therefore, media reports about these particles in drinking water do nothing more than unnecessarily scare consumers." 12The American Chemistry Council, which represents plastics manufacturers, declined to immediately comment. 13The Associated Press spoke with four co-writers of the study. All of them said they would cut back on their bottled water use. 14Columbia chemist Wei Min said he has reduced his bottled water use by half. Stapleton said she now depends more on filtered water at home in New Jersey. 15But study co-author Beizhan Yan, a Columbia environmental chemist who increased his tap water usage, pointed out that filters themselves can be a problem by introducing plastics. 16"There's just no win," Stapleton said. 17Outside experts, who praised the study, agreed that there is a general unease about the risks of fine plastic particles. Still, it is too early to say anything certain about the risks. 18"The danger of the plastics themselves is still an unanswered question. For me, the additives are the most concerning," said Jason Somarelli of Duke University in North Carolina. Somarelli was not part of the research. He added, "We and others have shown that these nanoplastics can be internalized into cells, and we know that nanoplastics carry all kinds of chemical additives that could cause cell stress, DNA damage and change metabolism or cell function." 19Somarelli said his own research has found more than 100 "known cancer-causing chemicals in these plastics." 20Dual laser microscope 21About 15 years ago, Min invented dual laser microscope technology that identifies specific compounds by their chemical properties and how they respond when exposed to lasers. Yan and Qian talked to him about using that technique to find and identify plastics that had been too small for researchers using established methods. 22Kara Lavender Law of the Sea Education Association said "the work can be an important advance in the detection of nanoplastics," but she said she'd like to see other chemists use the technique and get the same results. 23Yan said he is starting to study water supplies in the U.S. cities of Boston, St. Louis, Los Angeles and elsewhere to see how much plastics are in their tap water. Previous studies looking for microplastics and some early tests suggest there may be less nanoplastic in tap water than in bottled water. 24Even with unknowns about human health, Yan said he does have one suggestion: Use reusable bottles instead of single-use plastics. 25I'm John Russell. 26And I'm Ashley Thompson. 27Seth Borenstein reported on this story for the Associated Press. John Russell adapted it for VOA Learning English. 28________________________________________ 29Words in This Story 30sample - n. an amount of something that gives you information about the thing it was taken from 31brand -- n. a category of products that are all made by a particular company 32review -- v. to look at or examine (something) carefully especially before making a decision or judgment 33standardize - v. to change (things) so that they are similar and consistent 34tap water - n. water that comes through pipes from the public water system 35internalize -- v. to absorb or take in 36metabolism -- n. the chemical processes by which a plant or an animal uses food or water to make energy 37detect -- v. to discover or notice the presence of something