The water you get in bottles might be loaded with countless tiny plastic pieces, according to new research. These microplastics, which go from 1 nanometer to 5 millimeters in size, have been found nearly everywhere—from remote places like the Arctic to inside human placentas.
One estimate suggests Americans eat more than 44,000 microplastic pieces each year and breathe in over 46,000. However, measuring even tinier bits, known as nanoplastics, has been a challenge until lately. Nanoplastics are incredibly small—less than 1 nanometer, with a sheet of paper measuring about 100,000 nanometers thick and DNA strands at 2.5 nanometers. Experts think these particles, if swallowed, might breach the blood-brain barrier that shields the brain from toxins.
A recent study published in January in the Proceedings of the National Academy of Sciences suggests that drinking bottled water could lead to consuming up to 370,000 nanoplastic particles per liter. Researchers tested three brands of bottled water in the U.S., without specifying which ones. They discovered an average of 240,000 plastic bits per bottle, 90% of which were nanoplastics and the rest microplastics, which are about a thousand times bigger.
Back in 2018, a study found that 93% of samples from 11 bottled water brands in nine countries contained microplastics, averaging more than 300 particles per liter. However, this new research has determined that bottled water might have over a thousand times more nanoplastics.
There are concerns about these nanoplastics because they’ve been detected in human lungs and blood, suggesting they can bypass traditional bodily barriers. Researchers are now questioning how long these particles remain in the body, how they exit, and their effects during their stay. The recent study detected seven different plastic chemicals in water samples, with some being found in the bottles and caps themselves, leading researchers to suspect these materials shed into the water during packaging and transport. Others were detected that are not used in the packaging, indicating they might have entered the water beforehand.
Due to their minuscule size, nanoplastics can’t be filtered out, possibly originating from the source water or introduced during filtration. Given the pervasiveness of plastic in the environment, completely avoiding these particles is nearly impossible. However, now that measuring these particles is feasible, there could be advancements in developing filters to remove them.
There are at least 4,000 known chemicals used in plastic manufacturing, and their precise effects on human health remain largely unknown. Researchers believe this study could drive the scientific community to better understand how plastics impact human health. There’s speculation that such particles can cause harm by being inherently toxic or by carrying toxic substances, despite being relatively inert themselves.
One known harmful plastic chemical is Bisphenol A (BPA), which can harm reproductive and developmental health. The FDA has already prohibited BPA in products like baby bottles since 2012, but it’s still used in some food and drink packaging. Research shows that plastics, especially nanoplastics, can be absorbed by cells, potentially leading to oxidative stress, DNA changes, and inflammation.
Most studies on the health effects of plastic compounds have involved animals rather than humans. Some human studies, however, indicate that certain plastics like phthalates may lead to weight gain during pregnancy and raise the risk for gestational diabetes, though these findings are not conclusive.
There’s concern that chemicals like phthalates and BPA disrupt hormones, what scientists call endocrine disruption, particularly affecting those assigned female at birth. The Environmental Protection Agency considers DEHP, a commonly used phthalate, as a likely carcinogen, but it hasn’t been restricted like BPA.
Although current evidence on plastic ingestion and health isn’t definitive, scientists worry that ingesting plastic particles might have health impacts, similar to harmful effects from air pollution particles. Smaller particles are especially concerning because they are more likely to enter cells and penetrate the blood-brain barrier, with bottled water being a significant source.
Our limited understanding of the chemicals in plastics was highlighted in a 2019 study that examined eight common classes of household plastics. Researchers identified toxic chemicals in six out of eight types, but out of 1,400 compounds in these products, they could only identify 260.
Plastics can also absorb other substances, and if they encounter organic material or metals, they may release those into the body. Although how plastics and their additives affect human health isn’t fully understood, it’s clear that humans regularly consume plastic. This exposure level is definitely a reason for concern.
