BPA found in many grocery store foods

A research team from the University of Texas School of Public Health measured 105 human, cat, and dog foods from grocery stores in Dallas in March. They looked at fresh and canned food as well as food wrapped in plastic packaging. In 63 samples, they detected "quantifiable levels" of bisphenol A, often used to line food cans and to harden plastics.

Canned Del Monte Fresh Cut Green Beans was the worst offender of all products tested. Three cans contained between 26.60 and 65.00 ng of BPA per gram of food, which is equivalent to 26.60 to 65.00 ppb. Quantifiable levels of bisphenol A were found in cans of Chicken of the Sea Chunk Light Tuna in Water and in cans of Kroger Sweet Peas Garden Variety. Foods with plastic packaging, such as Chef Boyardee Spaghetti and Meatballs, had higher BPA levels than cans of the same food. BPA was detected in plastic-wrapped fresh sliced turkey. Canned Enfamil baby formula had more BPA than canned V8 juice.

Linda Birnbaum, a coauthor of the report, told Chemical & Engineering News that the low parts per billion levels detected are in line with previous reports on food from other countries and by U.S. environmental groups.

The levels found in the U.S. are nearly 1,000 times lower than the “tolerable daily intake” levels set by the by the Environmental Protection Agency (EPA) and the European Food Safety Authority (EFSA).

Whether the levels represent a concern, particularly for infants and small children, is under debate. Experts including Laura Vandenberg, a BPA researcher at Tufts University, and Fred vom Saal of the University of Missouri, Columbia, contend that EPA's BPA limit is too high.

Chemists have been formulating BPA-free can linings. The cans of tomato paste analyzed in the new study had non-detectable levels of BPA. Because acidic foods like tomatoes are known to enhance BPA leaching, the findings suggest that effective new linings exist and that companies are using them, says Ruthann Rudel of the Silent Spring Institute, a nonprofit research group.

Dr. Grout’s comment:

The take away message here is that consumer resistance causes the marketplace to change for the better. In March 2009, the six largest makers of baby bottles announced they would stop manufacturing baby bottles in the United States made with BPA. Last month, Canada added BPA to its official list of toxic substances, opening the possibility of regulating it. The FDA has not taken such action.

Epidemiological studies have linked human exposure to BPA with heart disease and diabetes in adults and abnormal behaviors in toddlers. Dozens of toxicology studies also connect BPA concentrations equivalent to the levels found in the U.S. population with a range of health problems. BPA is an endocrine disrupter - it acts like a hormone. It was discovered to be an estrogen in the 1930s.

Health standards established in the U.S. for exposure to toxic chemicals rest upon a core assumption: high-dose testing procedures adequately predict potential low-dose effects. A growing body of research now confirms that endocrine disruptors, like hormones, can also contradict the expectations of traditional regulatory testing.

Endocrinology is replete with cases in which hormone action at low levels differs dramatically from hormone action at high levels. For example, administering newborn mice a high dose (1000 μg/kg/day) of the estrogenic drug diethylstilbestrol (DES) causes weight loss in adult mice. In contrast, a dose of 1 μg/kg/day causes grotesque obesity in adulthood.