Monday, 28 November 2011
Canned soup ups BPA levels 1200% in urine
Consuming canned soups instead of fresh ones raises bisphenol A (BPA) concentrations in urine, a new study has suggested.
The study conducted by researchers at the Harvard School of Public Health (HSPH) found that a group of volunteers who consumed a serving of canned soup each day for five days had a more than 1,000 percent increase in urinary bisphenol A (BPA) concentrations compared with when the same individuals consumed fresh soup daily for five days.
“Previous studies have linked elevated BPA levels with adverse health effects. The next step was to figure out how people are getting exposed to BPA,” said Jenny Carwile, lead author of the study.
“We’ve known for a while that drinking beverages that have been stored in certain hard plastics can increase the amount of BPA in your body.”
“This study suggests that canned foods may be an even greater concern, especially given their wide use.”
Exposure to the endocrine-disrupting chemical BPA, used in the lining of metal food and beverage cans, has been linked with cardiovascular disease, diabetes, and obesity in humans.
The researchers, led by Carwile and Karin Michels, associate professor in the Department of Epidemiology, set out to quantify whether canned-soup consumption would increase urinary BPA concentrations relative to eating fresh soup.
They recruited student and staff volunteers from HSPH. One group consumed a 12-ounce serving of vegetarian canned soup each day for five days; another group consumed 12 ounces of vegetarian fresh soup (prepared without canned ingredients) daily for five days. After a two-day "washout" period, the groups reversed their assignments.
Urine samples of the 75 volunteers taken during the testing showed that consumption of a serving of canned soup daily was associated with a 1,221 percent increase in BPA compared to levels in urine collected after consumption of fresh soup.
“The magnitude of the rise in urinary BPA we observed after just one serving of soup was unexpected and may be of concern among individuals who regularly consume foods from cans or drink several canned beverages daily.”
“It may be advisable for manufacturers to consider eliminating BPA from can linings,” said Michels.
The study has been published in the Journal of the Medical Association (JAMA).