A
Montreal Gazette article about toxins in food by Joe Schwarcz, McGill 's Director of the Office for Science and Society, reminds me of a line in the movie
Hitch,
Sixty percent of all human communication is nonverbal body language; thirty percent is your tone, so that means ninety percent of what you're saying isn't coming out of your mouth.
Fabricated percentages aside, what applies to verbal communication also applies to text. There is no body language in writing, but the diction and arguments used set an important tone. Especially when writing in a daily newspaper, an author can hit the wrong chord with a single line or inappropriate title and fuel the same emotions he may be trying to abate.
Let's begin with the title of Schwarcz's piece(which could be his editor's, for all we know).
Relax - food chemicals can't hurt you
Health risks are proportional to the concentration of toxins in food, air and water. A responsible society is vigilant and sets limits on substances which research has revealed to be threatening from a medical and ecological perspective. But while it's possible to overdo it, impose needless bans and spend a great deal of energy worrying about minimal risks, such a "don't worry; be happy" title will get many people's backs up.
A conclusion's tone can also sting some readers and compromise good arguments from the body of the essay.
...And those numbers tell me that whatever “toxins” may be present are there at levels that are way below what regulatory agencies find acceptable. I know how the scientists at Health Canada, FDA and EPA determine these levels. I know their qualifications and level of expertise. I also know the same for their critics. I know whom to trust.
Although it's not intended, readers could accuse him of polarizing the issue by leading them to believe such issues are strictly about an unscientific, panic-stricken mob versus cool-headed experts. He refers to a 2010 study on endocrine disruptors sponsored by T
he Silent Spring Institute. They conclude that urine levels of bisphenol A (BPA) and bis(2-ethylhexyl) phthalate (DEHP) metabolites decreased significantly during a fresh foods intervention in 20 individuals from four different age groups. Schwarcz
pokes holes in the conclusion by arguing that the large drop occurs for toxin and metabolite levels that were already originally insignificantly small, and the changes occurred because BPA is metabolized quickly in humans
. But the group leader of the study Susan E. Fenton is certainly not unqualified.
She was the principal investigator at the U.S. Environmental Protection Agency's Reproductive Toxicology Division from 1998 to 2009. Prior to that she had completed a doctorate in endocrinology, followed by post-doc work in cancer biology. Aside from rewriting the conclusion, I would have added the following: in light of the fact that there are many other endocrine disruptors that are far more powerful, BPA has probably received a disproportionate amount of attention. For instance BPA is about 10,000 times less potent than estradiol. We are also lucky that primates, in a matter of hours, metabolize BPA to a gluconate derivative, which is not a disruptor. But concerns about BPA should not be totally brushed off due to ecological aspects. Fish seem to be the most BPA-sensitive organisms. Depending on whose guidelines one examines, the predicted no-effect concentrations in freshwater range from 0.175 to 1.7 nanograms per milliliter or parts per billion(ppb). The levels in human urine are close to or above that threshold based on the
much wider study in Canada, which
found concentrations in the 1-2 ppb range. Pre-intervention levels averaging 3.7 ppb were measured in
Fenton's subjects. There is a chemical cacophony in our bodies and environment. For a rational assessment we need a more educated public so that agencies and researchers are neither pressured into barking up the wrong tree nor lulled into being too passive. By using the wrong tone in our attempts to educate others and ourselves, we just add smoke to the fog.
Sources:
- Critical evaluation of key evidence on the human health hazards of exposure to bisphenol A
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3135059/
- Food Packaging and Bisphenol A and Bis(2-Ethyhexyl) Phthalate Exposure: Findings from a Dietary Intervention
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3223004/pdf/ehp.1003170.pdf
- Lead and bisphenol A concentrations in the Canadian population
http://www.statcan.gc.ca/pub/82-003-x/2010003/article/11324-eng.pdf