A recent study of bottled water, conducted by the journalism organization Orb Media, found that almost every major brand of bottled water is contaminated with particles of plastic.
The researchers tested 250 bottles of water—from nine countries and 11 brands. They dropped a red dye in each, which stuck to the plastic and glowed when passed under a certain light.
On average, in 93% of bottles, they found more than 10 pieces of plastic thicker than a human hair and hundreds of smaller pieces that the researchers and outside experts believe are probably plastic as well.
According to these findings, a person drinking an average amount of water from bottles could be consuming anywhere between hundreds and tens of thousands of microparticles a day.