NEW YORK (KGO) -- Here's something to consider the next time you reach for a water bottle -- you may be drinking more than H2O.
A new study claims a lot of bottled water may contain tiny pieces of plastic.
The research was conducted by a non-profit journalism organization called Orb Media.
Scientists ran tests on more than 250 bottles from 11 different brands worldwide.
They found an average of 10 plastic particles per liter.
So, is this a problem?
The World Health Organization tells the BBC it's launching its own review into the potential risks of plastic in drinking water.
"Samples came from 19 locations in nine countries on five continents including Brazil, China, India, Indonesia, Kenya, Lebanon, Mexico, Thailand, and the United States," said Orb Media in a press release.
The press release went on to state, "Ninety-three percent of bottled water showed some sign of microplastic contamination."
The study was supervised by Dr. Sherri Mason, Chair of the Department of Geology and Environmental Sciences at the State University of New York at Fredonia.
The BBC contacted the companies behind the brands and most responded, standing by the quality and safety of their products.
Click here for a look at other stories and videos about recent studies.
Study: Your bottled water may contain tiny particles of plastic