Bisphenol A, the highly controversial chemical found in food containers and other household products, is linked with heart disease and type 2 diabetes, new research suggests.
In a study of nearly 1,500 people, researchers in the United Kingdom found that subjects who were diagnosed with heart disease or diabetes had higher concentrations of BPA in their urine.
“There’s now a scientific question mark over the safety of bisphenol A in humans, especially in human adults, that needs to be followed up,” lead study author Dr. David Melzer, of Peninsula Medical School in Exeter, told CTV News.
The findings are published in the Journal of the American Medical Association.
BPA is a chemical used in the manufacture of a wide range of plastic consumer products, from beverage containers to dental sealants to car interiors.
Scientists cannot yet agree on how much BPA exposure is safe for humans.
BPA is so prevalent that it is detectable in more than 90 per cent of the U.S. population, the researchers noted.
Studies have found:
When mice are exposed to BPA they suffer severe health effects such as tumours and fertility problems.
Continuous, low doses of BPA affect communication between neurons in the brain, which help us understand and remember experiences.
A recent study by CTV News and the Globe and Mail found that BPA leached out of cans that were heated to temperatures similar to those used during the sterilization process.
In the wake of that research, Federal Health Minister Tony Clement announced that Canada would be the first country to label BPA a dangerous substance and would ban the use of BPA in baby bottles.
This study is the first research to find an association between normal levels of BPA exposure in humans with specific health problems, the researchers said.
“We were very surprised at all the results in the sense that this is the first big study in a human population,” Melzer said.
The scientists analyzed urinary BPA concentrations from 1,455 adults aged 18 to 74 who participated in the British National Health and Nutrition Examination Survey in 2003-2004.
Study subjects whose BPA readings were in the highest 25 per cent had three times the odds of developing cardiovascular disease and 2.4 times the odds of developing diabetes compared to subjects whose BPA levels were in the lowest 25 per cent.
However, the study does not answer how or if BPA might be causing diabetes or heart disease, Professor Jack Bend of the University of Western Ontario told CTV News.
“Based on this association, I wouldn’t myself be terribly concerned at this time,” Bend, a professor in the department of pathology, said. “BPA may contribute to chronic disease, but in fact we don’t have enough information to make that a real association.”
A spokesperson for a prominent Canadian environmental advocacy group said this new study supports the group’s call for a complete ban on the use of BPA.
“We need to just get rid of this chemical entirely from food packaging to protect adults as well as kids,” Environmental Defence’s Rick Smith told CTV News.
Melzer and his research team hope to release more data from their study by the end of this year.
Bisphenol A is mainly used to make a clear plastic polycarbonate which will withstand high temperatures, and epoxy resins to line the insides of tin and aluminium cans to prevent corrosion from the food and drinks they contain.
Some of the products which might contain bisphenol A include:
Hard clear plastic and some tinted water bottles
Hard clear plastic baby feeding bottles
Hard plastic baby toys
Food storage containers, plastic bowls and tableware
Cans of baked beans, soup, vegetables, fizzy drinks
Dental sealant to prevent cavities
Electronic equipment and CDs
Spray-on flame retardants