Terence Corcoran for Junk Science Week: No death by Bisphenol A
Posted: June 17, 2009, 8:35 PM by NP Editor
A new book rehashes all the now-familiar claims about how we live in a toxic chemical soup that is supposedly the cause of most ailments known to man
By Terence Corcoran
The number is 3,500. That’s the U.S. Environmental Protection Agency’s official limit on how much of the chemical Bisphenol A (BPA), measured by nanogram per millilitre, an average male can safely take in every day of his life for 70 years. It’s a very small number. A nanogram is one billionth of a gram.
Humans are exposed to Bisphenol A through contact with plastic bottles and containers, tin cans lined with protective coatings and other polycarbonate products. The EPA reference dose is based on its assessment of thousands of studies, including tests in which animals were injected with BPA and studies of humans exposed to it. The EPA, along with regulators in Europe and Asia, have concluded that the current incidence of BPA is safe for all, including babies. French Health Minister Roselyne Bachelot said in March that “baby bottles containing this chemical compound are innocuous.”
Now have a look at the graph above. It’s a reproduction from a new book,
Slow Death By Rubber Duck: How the Toxic Chemistry of Everyday Life Affects Our Health. Authors of the book are Rick Smith and Bruce Lourie. Mr. Smith is executive director of Environental Defence, one of Canada’s leading science scaremongers and lobbyists.
Slow Death is a rehash of all the now-familiar claims about how we live in a toxic chemical soup that is supposedly the cause of most ailments known to man — from cancer to genetic deformation, including turning men into women and vice-versa.
But
Slow Death has a fresh and simple gimmick. Through the book, Mr. Smith and his partner deliberately expose themselves to various chemicals in ways that more or less mimic normal behavior. They spray themselves with perfumes that contain phthalates, eat tuna fish allegedly loaded with mercury and test themselves for pesticide levels. The result: A lot of hoary rhetoric, a few meaningless graphs and some numbers that — despite the hype — prove the opposite of their intent.
The graph above, Rick’s BPA, reproduces the book’s report on one of those gimmick tests. It measures the amount of BPA in Mr. Smith’s urine after he had deliberately exposed himself to various products containing BPA. He drank coffee that would have contained traces of BPA, ate canned pineapple. Then he collected urine samples and sent them to a Harvard lab for analysis. The results, says Mr. Smith in the book, showed a “dramatic spike” in BPA levels. “I increased my BPA levels more than sevenfold from before exposure to after exposure.”
To attest to the alleged danger in the level of BPA in his urine, recorded at about 17.8 nanograms per millilitre, Mr. Smith turns to his favourite authority on BPA, Fred vom Saal of the University of Missouri. “Holy mackeral!,” said Mr. vom Saal. “This is really scary.” He said that if a baby were fed in the same way, this would be “very concerning.”
Notice how Mr. Smith dodges the first implication, which is that his BPA level might be dangerous to himself. Because BPA is flushed out of the average human within 24 hours, the 17.8 nanograms of BPA in each millitre of Rick Smith’s urine is roughly equal to his intake of BPA. How risky is this? The 17.8 nanograms is so far below the official U.S. reference dose as to be invisible and meaningless.
When I showed these numbers to Sam Kacew, associate director, Toxicology, at the McLauglin Centre for Population Health Risk Assessment at University of Ottawa, he called them “junk science.” Keith Solomon, Professor at Guelph University and a fellow at the Academy of Toxicological Sciences at Guelph University, said numbers on the BPA content of Rich Smith’s urine “are totally meaningless in a toxicological sense.”
Since Mr. Smith and the rest of us are clearly not at any risk from BPA or any of the other chemicals of daily life, Slow Death by Rubber Duck must depend on regurgitating the theories that have long been part of the bible of chemophobia.
First there’s the baby threat, even though just about every government in the world that measures these things has found no risk. Even the government of Canada, which banned baby bottles that might contain BPA, said there was no established risk to babies. Canada banned BPA bottles as a “precaution.”
If the false baby alarm doesn’t get attention, the next scare is the endocrine disruptor argument. The key expert on BPA in
Slow Death is Fred vom Saal of the University of Missouri, a man whose scientific research has been rejected, dismissed and/or disproven around the world.
But it is thanks to Mr. Smith and the media that popular fear of BPA and other chemicals continues to dominate public perception. A new record of that process by STATS at George Mason University, “Science Suppressed: How America became obsessed with BPA,” documents the spread of BPA junk science (stats.org). It should kill the popular obsession, except for the fact that people like Rick Smith and books like
Slow Death by Rubber Duck continue to attract attention, even though the risk they talk about is as real as the risk implied by Mr. Smith’s urine samples.
