Bisphenol A (BPA), Cancer and You

Bisphenol A (BPA), an organic compound used primarily to make polycarbonate plastic, epoxy linings for food cans and packaging, has been getting a significant amount of attention concerning its harmful effects on human health.

BPA is a well-documented xenoestrogen, a type of hormonal disruptor that acts like estrogen and interferes with the bodies’ level of this essential hormone. BPA can effect the bodies natural development stages including pre-natal and childhood development as well as pregnancy and menopause by either mimicking, enhancing or in some cases blocking the bodies use of estrogen. This can cause several negative long term health effects and has been linked to type II diabetes and breast cancer.

In 2008, the federal government declared BPA a toxic substance under the Canadian Environmental Protection Act and implemented regulations to ban the sale and importation of polycarbonate baby bottles because this particular age group is considered to be at a higher risk than others.

However, BPA is still widely used in many products that are available to most Canadians. For example, in a report published in March 2009 (http://bit.ly/bmqz33), Health Canada found BPA in at least 84% of canned pop sold in Canada. But the levels of BPA were so low that it would take an adult (60 kg body weight or 132 pounds) to consume approximately 940 canned drinks in one day to reach harmful levels.

Yet, there is a body of scientific literature, based on animal experiments that simulate conditions that could occur in humans, that has found harmful effects due to BPA at concentrations much below Health Canada's safety limit especially in populations that may be more at risk (Markey CM et al., 2001; Durando M. et al., 2007).

To air on the side of caution, there are a number of simple things we can do to limit our exposure to BPA (Griffin, 2009).

First, avoid using polycarbonate bottles, beverage cups and food containers. They are usually hard, coloured plastic, with the number 7 in the recycling triangle and the letter PC or OTHER underneath. They may also carry the trade name Lexan. Since many newer bottles made from an alternative material are also labelled with the number 7, it’s a good idea to make sure they’re specifically identified as BPA-free before purchasing them.

Second, use fresh or frozen fruits and vegetables wherever possible to avoid the BPA from can linings. When buying canned goods, choose those that are sold in bottles or jars instead of cans. One food processing company, Eden Organics, makes most of its products available in non-BPA cans. The exceptions are tomato-based products, which are too acidic for the alternative lining that is used with the other products.

Third, buy beverages in glass bottles rather than cans. BPA migration from beverage cans tends to be lower than from food cans but levels are highly variable depending on the contents and the manufacturer.

These are three simple things we can do to reduce the amount of BPA that our bodies absorb. If you would like more information concerning BPA or any other possible carcinogen as well as information concerning cancer prevention please feel free to leave a comment below.

References
Health Canada. (2009). Bureau of Chemical Safety Food Directorate Health Products and
Food Branch. Survey of Bisphenol A in Canned Drink Products. http://www.hc-sc.gc.ca/fn-an/securit/packag-emball/bpa/bpa_survey-enquete-can-eng.php. Accessed on June 15th, 2010.

Durando M, Kass L, Piva J, Sonnenschein C, Soto AM, Luque EH, Munoz de Toro M.
(2007). Prenatal bisphenol-A exposure induces preneoplastic lesions in the mammary gland in Wistar rats. Environmental Health Perspectives. January, 2007.

Griffen, Sean. (2009). Environmental exposure: The cancer smart guide to breast cancer prevention. Toxic Free Canada. Vancouver, Canada.

 Markey CM, Luque EH, Munoz de Toro M, Sonnenschein C, Soto AM. (2001). In utero
exposure to bisphenol-A alters the development and tissue organization of the mouse mammary gland. Biology of Reproduction, No. 65.