When you drink water from a plastic bottle, you’re literally swallowing plastic. An average liter of bottled water contains some 240,000 “nanoplastics” — particles that measure under one micrometer. That’s according to a new study from Columbia University researchers.
“These are particles of plastic that are smaller than 1/100th the width of a human hair,” describes Sherri Mason, a chemistry professor at Penn State University Behrend, who studies microplastics and freshwater plastic pollution. She was not involved in this research.
She explains that plastics are constantly shedding fragments, like humans sloughing off dead skin.
“Heat definitely makes plastics more brittle, and so they will shed more. If you leave a bottle of water, say, in your car as you go into the gym and then you come out and drink it — you taste the difference, right? That's mostly because of the chemicals that leach out as it's sitting in the sun. But definitely the heat makes the plastics more brittle. And so they're going to shed more as well.”
Plus, the motion of opening and closing the little cap on your bottle contributes to the problem. “If you think about a screw-top bottle … you have plastic rubbing on plastic. … That abrasion, that mechanical rubbing is going to shed more micro and nanoplastics.”
Mason says reusable bottles made from hard plastic are better than single-use, but recommends stainless steel bottles.
The study also focused on reverse osmosis filters that contain plastic membranes. Those release plastics into water too. “The fact that the filters themselves are releasing plastics into the water that you're trying to filter the plastics out of — if it sounds like a circular argument, that's because it is.”
Mason says it’s impossible to filter our way out of this problem. Instead, we need to reconsider our plastic use. She points out that bottled water is not regulated, and tap water is safer by design.
“We need to be thinking about reducing our relationship with this material. [If] plastic is less prominent in our society, we will find less plastic in the water. … Finding ways to reduce our plastic usage — that will help to reduce the plastic contamination of the environment, which will then reduce the plastic contamination of our bodies.”
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