Include low level BPA studies.
An article from Reuters discusses concerns about exposure to low levels of BPA from canned goods yet only covers effects of high doses of BPA on developing rodents, failing to mention the hundreds of studies that find adverse effects from low, environmentally relevant exposures.
Reporter Ernest Scheyder of Reuters writes a compelling piece that details BPA's use in the epoxy resins that line most metal food cans. The article would have been more complete if it had included the breadth of studies that show that low, environmentally relevant levels of BPA affect the development of the mouse and rat brain, mammary gland, prostate, female reproductive tract, and immune system, and also change behaviors in these animals.
In 2005, a study by Fred vom Saal and Claud Hughes showed that greater than 90 percent of the animal studies examining low doses of BPA found adverse effects of exposure. These doses of BPA, which are similar to human exposure levels, can have significant effects on developing rodents.
Because Scheyder does not include this body of research – encompassing more than 100 studies – some readers may interpret his discussion to mean that only high levels of BPA have been shown to cause harm. But this is not accurate. Specifically, the article points to research by Dr. Hugh Taylor at Yale University. His research illustrates that BPA exposure in the womb can change an animal's epigenetic patterns – the way genes are turned on or off without mutations in the DNA – that can lead to cancer during adulthood. The reporter then points to criticisms of Dr. Taylor's work, largely because very high levels of BPA were used to induce the epigenetic changes he observed.
BPA provides benefits to consumers, including preventing interactions between food and can materials and decreasing foodborne pathogens that can lead to food poisoning. However, its use in cans has come under scrutiny because it leaches from the cans into food, even under normal conditions of use and storage. Food and beverage cans may be a significant source of human exposure.
BPA exposure may also impact human health. It has been known since the 1930s that BPA is a synthetic estrogen, and estrogens can significantly affect development of fetuses, newborns and infants. Over the past few years, much attention has been given to BPA in baby bottles. BPA can leach from these bottles, especially when heated or cleaned. Because of consumer demand, many manufacturers have started making BPA-free baby bottles. While this may protect growing infants, other sources of BPA are likely to be items that pregnant women use – such as reusable plastic containers and canned foods.
Scheyder's story would have benefited from a discussion of the effects of low doses of BPA.
