I have written numerous blog posts describing the miscommunication of human health risks posed by chemistry and chemicals; covering topics from gypsy-moth spray to synthetic soccer fields. Frankly the fact that I have an entire section of this blog dedicated to the topic of “Toxicity and Risk” saddens me. What saddens me even more is how easily our media allow themselves to be drafted to serve as the publicity arms of various environmental activist groups’ fundraising campaigns. Well it happened again this week with some pretty poor reporting, and some egregious headlines, about a study called Buyer Beware: Toxic BPA & Regrettable Substitutes in the Linings of Canned Food prepared by a laundry list of activist organizations spearheaded by that stalwart bastion of objective, evidence-based policy and science: Environmental Defence.
As most readers probably know BPA (Bisphenol A) is an industrial chemical used to make hard plastics called polycarbonates as well as epoxy resins. As described by Health Canada, polycarbonates are used in a number of household products (notably baby bottles and other water storage containers) while epoxy resins are used as protective coatings in metal-based food and beverage cans. As almost everyone on the planet knows (or rather thinks they know) BPA is also a dangerous endocrine disruptor (not).
Endocrine disruptors are chemicals that can interfere with the body’s endocrine system by mimicking certain developmental, neurological and reproductive hormones (notably affecting estrogen and androgen receptors). They were first studied in depth in the mid-1990’s when a series of publications started exploring the effect of man-made chemicals on wildlife. It was generally recognized that these chemicals had very similar chemical characteristics. They almost invariably had two or more 5 or 6 carbon rings with the most effective endocrine disruptors being co-planar (that is the rings were in the same geometric plane like two plates lying next to each other on the same table). We all know that dioxins, PCBs and certain pesticides act as endocrine disruptors and what kid hasn’t heard about the frogs with the misshapen legs and alligators with stunted genitals.
Back in the early 2000’s, when not a lot was known about endocrine disruptors, BPA got labelled as one of the worst of the bunch. It became one of the poster-boys for the problem and as such the internet is absolutely filled with stories citing it as an endocrine disruptor. There is one minor problem with this narrative. It is wrong. As the poster-boy for endocrine disruptors a lot (and I mean a lot) of research has been done on BPA in the last decade and this research has determined that BPA isn’t such a bad actor after all. BPA is like the sketchy looking guy with all the tattoos, the shaggy hair and the leather jacket who your mom crosses the street to avoid passing on the sidewalk. Only later does she discover that he is a volunteer at the Salvation Army, a foster parent to troubled kids and does outreach for her church.
BPA looks pretty bad (oooh look, two benzene rings) but the rings aren’t actually coplanar (wait do those tattoos say “Jesus saves”?) and because of that it does not appear to have the level of effects that activists claim it should have. BPA is, as Douglas Adams would say: “mostly harmless”. Now you don’t have to believe me, instead go read up on the topic at Health Canada, the US Food and Drug Administration and the European Food Safety Authority. To quote Health Canada:
Health Canada’s Food Directorate has concluded that the current dietary exposure to BPA through food packaging uses is not expected to pose a health risk to the general population, including newborns and infants.
I can already hear the replies from the activists: but Environment Canada declared BPA “toxic”. Yes in 2010 BPA was indeed declared “toxic” under the Canadian Environmental Protection Act (CEPA). For those of you unfamiliar with the concept of toxicity (see the addendum below for a primer) this sounds scary. The problem is that declaring a chemical CEPA Toxic simply provides a means by which the government can regulate that chemical and frees up research funds to learn more about the chemical. As described in the order declaring BPA “toxic”(i.e. adding it to the List of Toxic Substances in Schedule 1 of CEPA 1999) BPA was not declared “toxic” for its effects on humans, but rather because at high concentrations, in industrial effluents from chemical plants, it is toxic to numerous aquatic species. As I describe elsewhere at this blog, a chemical’s toxicity is typically dependent on the dose and the route of exposure and the dose necessary to cause aquatic toxicity is pretty darn high…thus the reason I call it “mostly harmless”. The simple fact is that BPA can harm aquatic organisms in high concentrations but is not the human toxin the activists would have us believe it to be.
In 2010 when BPA was declared CEPA Toxic the knowledge-base on endocrine distruptors was in its infancy and the results were not all in. Since that time copious amounts of research has been done and a re-evaluation of BPA has taken place. The result of that re-evaluation is described by the US Food and Drug Administration (FDA):
In the fall of 2014, FDA experts from across the agency, specializing in toxicology, analytical chemistry, endocrinology, epidemiology, and other fields, completed a four-year review of more than 300 scientific studies. The FDA review has not found any information in the evaluated studies to prompt a revision of FDA’s safety assessment of BPA in food packaging at this time.
And what was the FDA’s conclusion about BPA?
FDA’s current perspective, based on its most recent safety assessment, is that BPA is safe at the current levels occurring in foods. Based on FDA’s ongoing safety review of scientific evidence, the available information continues to support the safety of BPA for the currently approved uses in food containers and packaging.
Having established that BPA is not the terrifying, child-maiming compound that the activists would have you believe, let’s look at the study highlighted in our scare-reporting du jour. As I noted, the reporting deals with a fairly lightweight report called “Buyer Beware: Toxic BPA & Regrettable Substitutes in the Linings of Canned Food”. The report presents a study of can linings from various food manufacturers. The first thing to acknowledge is that nowhere within the document (or the supporting documentation) do they actually give us a concentration or other useful piece of toxicological data. You see this report isn’t about human health, it is about publicity.
The most important thing to understand about this study is that it does not tell, nor did it examine, whether the food in the cans has any detectable concentrations of BPA. That may be what the publicists (and fundraisers) are trying to make you believe, but what the researchers actually did was to simply determine what kind of lining was used in each can.
The scientists used a metal tool to scrape the inside of the cans to get a sample of the coating which they then analyzed using a “Fourier transform infrared (FTIR) spectroscopy” (oooh nice sciency name). The result was simply an identification of the polymer used in the can lining, nothing more. Hoping for more (like say a concentration or a detection limit) I went to look at the raw data at Healthy Stuff (the people who actually conducted the science part of the study) and all they provided was a spreadsheet saying what polymer had been identified in what can. To be clear here, they didn’t test any food from these cans. Moreover, they had to use aggressive techniques to pull off enough material from the cans and lids to do their testing (because it is affixed so firmly) and even then they didn’t even tell us how much of the stuff was in there?
Knowing these facts let’s look at some of the bad headlines I discussed above. Well a couple of the worst came from CTV News ‘Alarming’ number of canned foods still contain BPA, new report warns [scare quotes theirs] and Global News: Report sounds alarm over discovery of BPA in Canadian canned food. You might ask why I find these two headlines so egregious? Well as I explained above both completely misrepresent the contents of the report they are purportedly describing. As we now all now know, no canned foods were tested in the study, the cans were tested not the foods inside. So we are getting breathless headlines and media reports about a safe (at the doses encountered) chemical that is strongly affixed to cans (not tested in food). Looking at the report in this light maybe the producers should not have led their newscasts with this story. But don’t worry; Environmental Defence got their name mentioned on TV, and in print, so their fundraisers will be happy.
What I find most problematic about this report, however, is the underlying message it sells: that canned foods are not safe. Imagine there was a technology that allowed for the storage and preservation of both uncooked and prepared foods. In an ideal world the technology would be inexpensive; while being highly resistant to breakage and temperature change. It would allow for the long-term storage of said foods irrespective of climate while reducing spoilage rates; all without the need for energy intensive appliances to keep the food safe to eat. Sounds like a pretty miraculous technology doesn’t it? Happily for humanity it was discovered generations ago. The technology is called canning and it has been a staple of the food industry since the 1800’s.
When initially invented, canning had serious issues with lead seals that leached lead into the canned food; with corrosion of the cans; and if the cans were dented, then spoilage. Happily lead was removed from cans and an advance was made on canning with the development of epoxy liners that could be used to coat the cans making them even safer. According to the U.S. FDA, there has not been a reported case of food borne illness from the failure of metal packaging in close to 40 years, or the equivalent of trillions and trillions of canned foods sold.
Now look at the report a second time, the first part is about BPA but the second part goes about the task of systematically undercutting every possible alternative to BPA in food cans. The report isn’t just about getting rid of BPA lining of food cans, it is about getting rid of food cans altogether. Essentially a generation of chemophobes is working very hard to overturn a century of safe food storage technology and return us to a time when food was stored in glass jars with temporary seals. Alternatively, they would have us rely on fridges to keep our food edible. Both options sound pretty good to urban hippies who delight in buying fresh artisanal vegetables at their nearby Whole Foods but both leave a lot of northerners, country-folk or people with unreliable power supplies without a lot of food choices.
As anyone who has followed my blog knows, the fear of chemicals (chemophobia) runs rampant in our modern times. I believe this is a direct result of the loss of a critical mass of scientifically-trained individuals in jobs outside of science in our society. No longer is the media and civil service loaded with science grads. Instead we are seeing a split between the scientifically literate and those I call the “science-blind”. That is folks who are functionally illiterate on topics of science and simply take for granted all the wonderful things that science has brought into their lives.
As the scientifically literate it is our task to fight back against these chemophobes who would unnecessarily disrupt our food production and storage system. Like the activist NGO’s fighting against Golden rice (and in doing so dooming a generation of children to blindness) these activists are working hard to undercut a modern health miracle. Sadly, most of them probably don’t even realize they are doing so. The saddest part is that our media, with its dire shortage of scientifically-trained reporters, are helping them in their tasks. Instead of asking the right questions the reporters are instead regurgitating talking points written for them by the activists and spoon-fed in the form of useful talking points and media guides (or media backgrounders as they call them). The sad part is that most of them do not even understand or know what they are doing. Their absence of a science education leaves them open to such manipulation.
Addendum on Risk and Toxicity
I have written a lot at this blog about how risk is communicated to the public and I have prepared a series of posts to help me out in situations like this. The posts start with “Risk Assessment Methodologies Part 1: Understanding de minimis risk” which explains how the science of risk assessment establishes whether a compound is “toxic” and explains the importance of understanding dose/response relationships. It explains the concept of a de minimis risk. That is a risk that is negligible and too small to be of societal concern (ref). The series continues with “Risk Assessment Methodologies Part 2: Understanding “Acceptable” Risk” which, as the title suggests, explains how to determine whether a risk is “acceptable”. I then go on to cover how a risk assessment is actually carried out in “Risk Assessment Methodologies Part 3: the Risk Assessment Process. I finish off the series by pointing out the danger of relying on anecdotes in a post titled: Risk Assessment Epilogue: Have a bad case of Anecdotes? Better call an Epidemiologist.