The results of a new study which has linked a chemical commonly used to make plastic containers, to human diseases, is adding to an already heated debate about he safety of such products.
The study has found a 'significant relationship between urine concentrations of the environmental estrogen bisphenol A (BPA) and cardiovascular disease, type 2 diabetes and liver-enzyme abnormalities'.
This is the first time BPA has been shown to directly cause harm to humans and until now, environmental and consumer activists questioning the safety of the chemical's use have only had ammunition for their argument from research showing BPA exposure harmed laboratory animals.
The British researchers analysed urine and blood samples from 1,455 American adults aged 18 to 74 who were representative of the general population and they found that the 25% with the highest levels of bisphenol A in their bodies were more than twice as likely to have heart disease and, or diabetes compared to the 25% with the lowest levels.
The researchers say this is the first ever study that has been on the general population and their findings are in line with what has been found in animal models - but add that the design of the study did not allow for anyone to conclude BPA causes heart disease and diabetes.
The study authors say further research will be needed to understand whether these statistical associations have any relevance at all for human health - but they say the chemical is present in more than 90% of people.
The Food and Drug Administration (FDA) in the U.S. is being urged to reconsider the safety of BPA and Frederick vom Saal of the University of Missouri and John Peterson Myers of the nonprofit U.S.-based Environmental Health Sciences are calling for the FDA to follow Canada and declare BPA a 'toxic chemical' requiring "aggressive action to limit human and environmental exposures".
Since 1997, research from vom Saal and other MU colleagues have shown adverse health effects of BPA at exposure levels below those currently considered safe by the FDA and he says despite growing research that confirms BPA is dangerous to the health, the FDA and the European Food Safety Authority have chosen to ignore warnings from expert panels and other government agencies and have continued to declare BPA as 'safe'.
Earlier this year Canada decreed BPA was harmful to infants and toddlers and announced plans to ban some products.
BPA is used to make polycarbonate plastic, a clear shatter-resistant material in products ranging from baby and water bottles, plastic eating utensils, sports safety equipment and medical devices and is also used to make durable epoxy resins used as the coating in most food and beverage cans and in dental fillings.
People can consume BPA when it leaches out of plastic into liquid such as baby formula, water or food inside a container.
Previous studies have shown adverse health effects of BPA on the brain and reproductive system, as well as metabolic diseases in laboratory animals.
In the study, the team said the chemical is present in more than 90% of people, suggesting there is not much that can be done to avoid the chemical of which over 2.2 million tons is produced each year.
The researchers will present their findings to the FDA this week say session it is too early to identify a mechanism through which the chemical may be doing harm.
The researchers also caution that their findings are preliminary and more work is needed to determine if the chemical actually is a direct cause of disease.
The researchers say BPA is one of the world's most widely produced and used chemicals.
vom Saal says any government action to reduce exposure may offer an effective intervention for improving health and reducing the burden of some of the most consequential human health problems and would be good news.
The research is published in the current issue of the Journal of the American Medical Association (JAMA).