(CINCINNATI) -- The plastic water bottles so many of us chug from all day could have hidden health risks.
Researchers at the University of Cincinnati say that polycarbonate or "soft plastic" bottles can leak a dangerous chemical called BPA into the liquid inside the bottle.
It's even riskier when the bottles are filled with hot liquids.
"It interferes with reproductive function, has been linked to estrogen responsive cancers, breast cancer and prostate cancer. And now having evidence that it could have some association with obesity," said UC Researcher Scott Belcher.
Belcher says that it's unclear as yet what level of exposure to BPA is considered harmful.