New research is suggesting that bottled water may not be the health-alternative to tap that everyone seems to believe it is. The study revealed that single-use bottles made of plastic have the same chemical disinfectants that are found in tap water. They looked at tap water around the San Francisco bay area, as the location has some of the strictest water safety requirements in the entire country.
The study’s authors noted that there were varied levels of lead, chemical byproducts, and bacteria across their experimental sources. Their presence in water can cause liver damage, cancer, and neurological problems if the dose is high enough. They did note that the amounts they detected at all the sites were below the federal safety standards for drinking water set by the EPA.
Senior Scientist Samantha Bear with SimpleLab is the lead author of the report. Bear said they were surprised to realize that there weren’t dramatic differences between bottled and tap water. She also noted that using a commercially available Brita filter didn’t significantly reduce common contaminants.
They tested 100 samples of bottled water, 603 samples from home taps, and 111 samples from home taps that were treated by Brita filtration. The bottles included products labeled as purified, well, mineral, and artesian water. They were acquired in July 2022. Researchers did not mention specific brands for the bottled water, but said they were a representative sample of typical products available in California.
The water testing kits used are commercially available from SimpleLabs, and the study is available in the journal for The Public Library of Water Science.
Results from the analysis suggested that 61% of home filtered, 98% of untreated home, and 53% of bottled waters they tested had at least one contaminant that was dangerous to human health. Most common was the presence of trihalomethanes, a chemical byproduct from chlorination which is used to disinfect water. The highest levels of the chemical were found in tap water. Eight of the samples exceeded state safety requirements and the chemical can cause neurological problems and liver damage.
