What does it mean that scientists found 240,000 million nanoparticles of plastic in a typical bottle of water? The number is big and sounds alarming, but it isn’t very informative. How many particles are needed to cause disease? What kinds of ailments are likely to result? Are there people who are dead now who’d be alive if they’d avoided bottled water?
These questions need to be addressed before we can make informed decisions at the individual and societal level. Should we ban plastic bottles for water and other drinks? Require health warnings? Would doing so save lives — or would it only take attention and money from more pressing health problems?
Nanoplastics are smaller than a wavelength of light — too small to see with an optical microscope. Previous studies showed they were there, including one published in Nature Scientific Reports in 2021, demonstrating how to detect them in bottled water.
The new study, published in the Proceedings of the National Academy of Sciences, revealed more particles per bottle than the 2021 study, though it wasn’t clear why the two methods got such different results.
What consumers need to know is how much plastic is in a glass of tap water versus bottled water, and whether reusable bottles — which are often made of harder plastics — face the same problems as cheaper plastic bottles. Do home filtering systems add or remove plastic nanoparticles?
Questions about the health impacts of nanoparticles getting into the body are hardly new, points out retired industrial chemist Mark Jones. Health implications of inhaled nanoparticles from gas stoves, wood fires, candles, cigarettes, e-cigarettes, diesel engines and more are well studied. We are all exposed, in many cases to far more nanoparticles than are present in bottled water. Airborne nanoparticle concentration is most commonly reported in weight per volume of air and exposure tracked by mass. But is it the total amount of plastic or the number of pieces that matter most?
We don’t ingest quite as much plastic as the media has widely reported. In the last several years news organizations have been repeating we eat about a credit card’s equivalent in plastic every week. That figure, five grams, is dubious. Other scientists have found major errors in that analysis and subsequent studies give estimates a million times lower.
It’s hard to do direct human studies on long-term effects, but a small study showed there was more plastic in people with liver disease than those with healthy livers, and another small study found plastic particles in human blood clots.
Some studies suggest that not all plastic particles are equally dangerous. Some studies showed noticeable health effects only from plastics with certain additives not found in water bottles.
The plastic problem can seem overwhelming when particles get inside our bodies from the air we breathe, the food we eat and the beverages we drink. Tackling the problem requires more information about sizes and kinds of particles that are most dangerous and where they come from.
Cutting back on water is not the answer — hydration is vital for health. Not to mention that exercise is good for us, and it’s much easier and more fun to be active when you’re not dehydrated.
So perhaps as a first step we could demand more drinking fountains, more water coolers, and studies that vouch for the safety of reusable bottles. Maybe there is a technology fix, something that can be done to reduce the production of the particles. There could be demand for new forms of packaging. And there could be a new demand for water and other drinks sold in glass bottles.
But enough alarming data has now amassed that it’s time to move from fear and outrage to action.
F.D. Flam is a Bloomberg Opinion columnist covering science.
