Hot Liquid Ups BPA From Plastic Bottles
Study: Chemical Released More Quickly With Boiling Liquids; Risk to People Not Clear
Same Levels in New and Old Bottles
Belcher collected used polycarbonate water bottles from his local climbing gym and purchased new ones from a nearby outdoor activities store.
All the bottles were subjected to seven days of testing designed to simulate normal use during backpacking and camping conditions.
Whether they were new or used, the bottles released the same average amount of bisphenol A at the same rate when exposed to cool or temperate water.
"There is some thinking that the longer a bottle is used the more BPA it releases, but that isn't what we found," Belcher says.
But much higher levels of bisphenol A were released when the bottles were briefly exposed to boiling water. The rate of release after exposure to boiling water ranged from 8 to 32 nanograms per hour, compared with a range of 0.2 to 0.8 nanograms per hour under room-temperature conditions.
And the speed of release was 15 to 55 times faster, Belcher says.
He adds that the findings have made him reassess his own habits.
"I don't put hot tea or hot water in these bottles when I'm climbing anymore," he says. "And I have retired my polycarbonate French-press coffeemaker."
What the Experts Say
The two expert panels that recently weighed in on the safety of bisphenol A reached different conclusions.
The National Toxicology Program's Center for the Evaluation of Risks to Human Reproduction (CERHR) convened a 12-member panel made up of government and non-government scientists to review the scientific evidence.
The group concluded that bisphenol A exposure levels for most Americans were well within the Environmental Protection Agency's standards and found no major health risks associated with exposure.
The panel did express "some concern" that the chemical could cause behavioral and neurological problems in developing fetuses and young children, however.
Another panel made up of 38 researchers who have studied BPA concluded that levels of the chemical seen in humans are higher than those that caused adverse effects in animal studies.
The group also expressed confidence that even low doses of BPA can have biological effects.