Thursday, February 12, 2015

Snoopy is Safe After All

Snoopy Is Safe After All

Rest easy, beagles. Another chemical scare looks like a false alarm.

Feb. 11, 2015 – © The Wall Street Journal

The periodic scares over chemicals in vaccines, foods and other products are typically a war on the periodic table, and one compound that on all of the evidence deserves exoneration is bisphenol-A, or BPA. The latest research deserves more attention before more federal dollars are wasted.

BPA is used in the lining of metal cans and plastics to ensure structural integrity and keep things like E.coli out of food. It has been widely used for more than 50 years as a coating in everything from soup cans to bike helmets. The chemical has undergone testing in more than 4,500 studies over three decades, and the Food and Drug Administration has twice affirmed, most recently in November, that human exposure to low levels of BPA isn’t dangerous.

Anti-chemical activists have nonetheless maligned BPA as a toxic substance that might act as an “endocrine disrupter” by mimicking hormones in the body. BPA has been allegedly linked to cancer, obesity, impotence, you name it. Many companies such as the water-bottle maker Nalgene have stopped using it and label their products “BPA-free.”

The latest study, published in January by Justin Teeguarden of the Pacific Northwest National Laboratory and FDA researchers, knocks down the idea that humans could be at risk of absorbing high levels of BPA into the bloodstream. The researchers fed people tomato soup with traceable BPA—and the body essentially neutralized 998 out of every 1,000 BPA molecules. The entire BPA sample moved through the body in 24 hours.

The fear that BPA might be absorbed into the bloodstream caught traction thanks in part to a 2013 study in which the authors slipped BPA solutions under the tongues of sleeping beagles and found that the pups absorbed more BPA in their blood than other animals had in previous studies. BPA opponents waved around the Snoopy scare as evidence that the chemical was unsafe, calling on regulators to reconsider their all-clear messages.

Now the question is: How many more taxpayer-funded BPA studies are really necessary? The National Institute of Environmental Health Sciences, an arm of the National Institutes of Health, has shelled out more than $100 million for research on BPA since 1997. Three prominent BPA critics have received $20 million and have failed to turn up causation between BPA and adverse health effects. Yet the studies always conclude that more research is needed and so the grants are renewed. Nice work if you can get it.

Scientists and politicians claim there isn’t enough federal research funding to support all of today’s important projects. Here’s one idea: Reallocate the money for redundant BPA studies into something more productive.

Friday, January 23, 2015

European Food Safety Authority Says BPA is Safe

"This opinion describes the assessment of the risks to public health associated with bisphenol A (BPA) exposure. Exposure was assessed for various groups of the human population in three different ways: (1) external (by diet, drinking water, inhalation, and dermal contact to cosmetics and thermal paper); (2) internal exposure to total BPA (absorbed dose of BPA, sum of conjugated and unconjugated BPA); and (3) aggregated (from diet, dust, cosmetics and thermal paper), expressed as oral human equivalent dose (HED) referring to unconjugated BPA only. The estimated BPA dietary intake was highest in infants and toddlers (up to 0.875 μg/kg bw per day). Women of childbearing age had dietary exposures comparable to men of the same age (up to 0.388 μg/kg bw per day). The highest aggregated exposure of 1.449 μg/kg bw per day was estimated for adolescents. Biomonitoring data were in line with estimated internal exposure to total BPA from all sources. BPA toxicity was evaluated by a weight of evidence approach. “Likely” adverse effects in animals on kidney and mammary gland underwent benchmark dose (BMDL10) response modelling. A BMDL10 of 8 960 μg/kg bw per day was calculated for changes in the mean relative kidney weight in a two generation toxicity study in mice. No BMDL10 could be calculated for mammary gland effects. Using data on toxicokinetics, this BMDL10 was converted to an HED of 609 μg/kg bw per day. The CEF Panel applied a total uncertainty factor of 150 (for inter- and intra-species differences and uncertainty in mammary gland, reproductive, neurobehavioural, immune and metabolic system effects) to establish a temporary Tolerable Daily Intake (t-TDI) of 4 μg/kg bw per day. By comparing this t-TDI with the exposure estimates, the CEF Panel concluded that there is no health concern for any age group from dietary exposure or from aggregated exposure. The CEF Panel noted considerable uncertainty in the exposure estimates for non-dietary sources, whilst the uncertainty around dietary estimates was relatively low."

© European Food Safety Authority, 2015