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bisphenol a

Science Suppressed:
How America became obsessed with BPA



What the Journal Sentinel didn't report (cont'd)

Germany’s Federal Institute for Risk Assessment and baby bottles; Norway and Switzerland’s analysis of BPA migration; France’s Food Safety Agency
The Journal Sentinel also failed to report that Germany’s BfR Federal Institute for Risk Assessment had separately reviewed the safety of BPA and concluded that:

“Following careful checking of all the studies, in particular those studies in the low dose range of bisphenol A, the BfR carried out a scientific assessment of the results and came to the conclusion that the presence of bisphenol A in polycarbonate bottles poses no health risk to babies and infants during normal use. The BfR is not alone in this assessment of the situation: the European Food Safety Authority (EFSA) and the American Food and Drugs Administration (FDA) share this view. Japan, which has carried out its own investigations into problems associated with BPA, also saw no need for a ban.”

The BfR also dismissed the idea animating Canada’s decision to label BPA toxic, namely that BPA in polycarbonate baby bottles posed a risk to children:

“Official food monitoring could not detect any bisphenol A during spot checks on the contents of baby bottles that were heated under normal domestic conditions. The BfR does not recognize any health risk for babies that are fed from baby bottles made of polycarbonate. Stopping the use of polycarbonate bottles is an unnecessary step, in the opinion of the Institute.”

In contrast to official food monitoring and spot checks, the Journal Sentinel repeatedly warned readers about the dangers of BPA in polycarbonate bottles, for example on October 19, 2008:

“Studies have shown the main sources of exposure for newborns and infants are from bisphenol A migrating from the linings of cans into liquid infant formula and migrating from polycarbonate baby bottles into the liquid inside after the addition of boiling water.”

The paper called on the government to ban BPA in plastics used by children (November 18, 2008):

“It should ban BPA from polycarbonate bottles and tableware intended for small children"

And it recommended not placing warm liquids in such products (November 16, 2008):

“If using hard polycarbonate plastics (water bottles, baby bottles or sippy cups), do not use for warm or hot liquids”

But the paper failed to report a joint study published in February 2008 in the journal European Food Research and Technology by Per Fjeldal of the Norwegian Food Safety Authority and Sandra Biedermann-Brem and Koni Grob of the Official Food Control Authority of the Canton of Zürich that examined the worst case scenarios for BPA leeching from baby bottles.

The maximum amounts of BPA these researchers managed to extract from bottles under normal washing conditions was between 1 and 7 micrograms per liter (μg/l) of fluid. Given that the European Union’s Tolerable Daily Intake for BPA for infants is 250 micrograms per liter of fluid, the researchers concluded that:

“[T]he amount of BPA contained in the polycarbonate is so small that BPA migration in the proper sense is below 1 μg/l; also liquids with a strong extraction power do not extract much BPA.

BPA is formed and transferred into the beverage when alkali aqueous solutions are “baked” onto the polycarbonate during the drying process, as it occurs when the washing liquid is poured out, but rinsing with water fails. However, the BPA still amounted to less than 10 μg/l when referred to a 100 ml filling

With this understanding of the mechanisms of BPA formation and transfer into beverages it seems possible to confirm that even under extreme conditions and scenarios the amount of BPA released from polycarbonate baby bottles is clearly below the TDI for babies. In particular it can be ruled out that the observed increase of BPA release with aging of the bottle may extend to levels which could be of health concern.”

A follow up study by Biedermann-Brem and Grob (published online in November 2008 in European Food Research and Technology) added significantly to our understanding of BPA exposure from polycarbonate bottles. Exposure was not an issue due to normal migration from the polymer, the levels in the food or liquid content were below one microgram per liter; the problem was degradation. If you boil tap water, you increase its alkalinity, which makes the water more caustic, which in turn strips more BPA from the bottle.

“BPA concentrations may reach 50 [micrograms per liter] if a polycarbonate bottle is sterilized by boiling water in it (well feasible only by means of microwave heating) and this same water is used to prepare a beverage. Increased concentrations are also observed when boiling hot beverages with a high pH are filled into the bottle, such as boiled plain water or tea.”

The paper noted that higher amounts of BPA release through degradation required unrealistic test situations – such as boiling water in a bottle continuously for an hour or more. The researchers concluded that realistic daily exposures would be unlikely to reach 50 micrograms per liter, an amount considered safe for infants by EFSA. As the researchers note,

“Assuming a daily consumption of 800 ml from baby bottles and a body weight of 4 kg, the TDI [Tolerable Daily Intake] of 0.05 mg/kg bw would be reached with a BPA concentration of 250 micrograms per liter.”

If you wanted to reduce that low level of exposure a hundred fold (and satisfy Canadian concerns about uncertainty), the researchers noted that you should “not boil water to be used for preparing drinks in a polycarbonate bottle,” or fill a polycarbonate bottle with hot water or tea, and you should rinse such bottles after they are washed in a dishwasher.

In October 2008, the French Food Safety Agency – Agence française de sécurité sanitaire des aliments (AFSSA) – was asked by the French Department of Health to study Canada’s decision to ban BPA in baby bottles. AFFSA conducted an evaluation of the evidence and concluded that there was neither cause for concern nor a need to regulate BPA according to precautionary principles.

Again, the failure of the Journal Sentinel to cover any of this research creates a false numerical sense of risk when it reports on BPA in baby bottles.

The Journal Sentinel does not mention that a 2005 Japanese risk assessment on BPA,  produced by The Research Center for Chemical Risk Management, concluded that:

“[C]urrent BPA exposure levels were unlikely to pose unacceptable risks to human health.”

NSF International
But perhaps the most perplexing omission of all, given the recurring theme in the Journal Sentinel’s reporting of “independent” research being ignored by regulatory agencies, was that in 2008 the paper ignored the most comprehensive independent evaluation of the research on BPA, conducted by NSF International. An independent, not-for-profit organization devoted to consumer protection, NSF started in 1944 as the National Sanitation Foundation in the Public Health department of the University of Michigan, Ann Arbor, and has expanded over the years to 18 countries. It is a collaborating center with

the World Health Organization on food and drinking water safety, and it has expanded its monitoring operations in China following a series of public health controversies over lead in toys.

NSF International won a competition to run the EPA’s direct and  indirect drinking water additives regulatory program in the mid-1980s, and decided to develop a drinking water limit for BPA in the absence of federal limits or guideline values for BPA that might be detected in water through a plastic component in faucets or pipes.

NSF’s review of the research on BPA calculate a reference dose (in European-speak, a Tolerable Daily Intake, TDI) or how much BPA can be safely ingested on a daily basis. The result was published in the peer-reviewed Journal of Toxicology and Environmental Health in February. The conclusion? BPA does not pose a health risk to adults or infants at present exposure levels.

No matter what position one takes on BPA scientifically, the failure to address such a huge body of counter-evidence is stunning. The Journal Sentinel reporters managed to avoid anything that might have contradicted the thrust of their reporting. This kind of confirmation bias is one of the problems of investigative reporting in general: the need to justify spending scant resources covering a topic in immense depth can lead reporters to discount information that could wind up wrecking their whole project.

Next - How the Milwaukee Journal Sentinel sourced its reporting.


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