Foreign Property News | Posted by Hnin Ei Khin
The bottled water you drink may contain hundreds of thousands of microscopic pieces of plastic, new research shows.
Microplastics—tiny bits of plastic that range in size from 1 nanometer to 5 millimeters in diameter—have been widely studied in recent years and have been found virtually everywhere on Earth, from the far reaches of the Arctic to the lining of human placentas.
One analysis estimated that Americans ingest more than 44,000 microplastic particles every year and inhale more than 46,000. But until recently, scientists couldn’t reliably measure even smaller particles, called nanoplastics.
Nanoplastics are less than 1 nanometer in size—a sheet of paper is about 100,000 nanometers thick, and a strand of DNA is 2.5 nanometers—and experts believe that if ingested, these bits of plastic can cross the blood-brain barrier, which protects the brain from toxins.
The new study, published in January in the Proceedings of the National Academy of Sciences, estimated a human may consume as many as 370,000 nanoplastic particles in one liter of bottled water.
For the new study, researchers tested three brands of bottled water sold in the United States, though the authors did not disclose which brands they included.
They found that the water harbored an average of 240,000 pieces of plastic, 90% of which were nanoplastics. The remaining 10% were microplastics, about a thousand times larger than nanoplastics.
A 2018 study first identified microplastics in 93% of samples taken from 11 types of bottled water sold in nine different countries. The average was more than 300 microplastic particles per liter.
However, the new study found a plastic bottle of water may contain more than a thousand times as many nanoplastics.
“The concern with the nanoplastics in particular is that they have been found in human lungs and blood,” Phoebe Stapleton, PhD, an associate professor of pharmacology and toxicology at Rutgers University who co-authored the new study, told Health. “Because these nanoplastics are so small, they cannot get filtered out."said Stapleton, adding that nanoplastics may also have been introduced during the filtration process itself.
Laboratory studies have found that exposure to polystyrene nanoplastics (PS-NPs) can lead to a range of toxicological effects, including reproductive abnormalities (Li et al., 2020a; Li et al., 2020b), oxidative stress and gastrointestinal dysfunction (Chae and An, 2017), increased mortality (Liu et al., 2020), growth inhibition and disorders, and neurotoxicity (Zhang et al., 2020).
