A study in the Journal of the American Medical Association found eating canned soup for five days could boost BPA levels by 1,221 percent

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The chemical additive bisphenol A (BPA) isn't gaining many fans these days. The research keeps showing that not only is the compound linked to more reproductive and developmental problems than previously thought, it's also found in more types of materials than we'd like to believe.

BPA has long been known to be present in plastic water bottles, and recently it's also been shown to lurk in aluminum bottles that are lined with epoxy resin. Many baby bottles and reusable drinking bottles are now advertised as being BPA-free, and with good reason, according to a string of recent studies suggesting that the hormone disruptor can pose some potentially serious risks, like interfering with female fertility, and affecting the development of the fetus.

The researchers who headed a current study wanted to see what other types of containers might contain BPA. "The next step was to figure out how people are getting exposed to BPA, says lead author Jenny Carwile. "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."

To see whether canned foods might affect BPA levels in the body, Carwile and her colleagues had 75 participants eat either a 12-oz serving of canned or fresh soup for five consecutive days. Then, after a two-day rest period, the groups switched and ate the opposite of what they had started with. The researchers measured their urinary BPA levels over the course of the study period.

They found a considerable change in urinary BPA concentration over the study's short duration: When the participants ate canned soup, their BPA levels rose by 1,221 percent, compared with fresh soup eaters.

"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 Karin Michels, senior author of the study.

BPA is found in a variety of products, from medical equipment to dental sealants. It may be a good idea to cut down on eating foods kept in containers containing BPA as much as possible, until manufacturers make changes to the ways in which containers are constructed and lined. More research will be needed to determine exactly how long one's BPA levels stay raised after ingesting it. For more information on BPA, see the FDA's website on the subject.

The research was conducted at the Harvard School of Public Health, and was published in the November 22, 2011, issue of the Journal of the American Medical Association.

Image: Carlos Caetano/Shutterstock.

This article originally appeared on TheDoctorWillSeeYouNow.com, an Atlantic partner site.

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