Jan 12, 2010
Chemophobia and risk
As a chemist by training, I’ve always been loath to give credence to unfounded criticism of synthetic chemicals that might stoke up chemophobia. Indeed, on several occasions I have written about how our bodies have evolved to cope with all kinds of chemicals regardless of whether they are synthetic or “natural”. I’ve never been a shill for the chemical industry, although I have been accused of it. But, there is so much misguided nonsense about the supposed absolute risks of synthetic chemicals that someone has to provide a little balance.
On at least one occasion, however, I’ve been thwarted in my efforts to provide just such a balanced point of view the issues surrounding chemical safety. Once it was a blinkered features editor on a well-known popular science magazine who simply refused to see past the word “manmade” and had already decided that if the product being discussed wasn’t derived from an extract of hemp or some other natural material and squeezed out by native bushpeople or some such nonsense then it didn’t deserve a mention in the hallowed pages of the magazine.
As a science, chemistry is more than wonderful, it not only sates the inquisitive and repeatedly throws up new puzzles, it also provides us with the materials with which we have built the modern world. As with any human endeavour there is, of course, a price to pay. Many of the essential ingredients of the industrial processes on which our standard of living depends are toxic. There is no way to avoid that issue. Volatile organic compounds are a case in point and several of the most toxic are now banned substances on health and environmental grounds.
Toxicity, however, is about exposure and dose, not about blanket bans. That said, it is sometimes necessary to take a more holistic view of the potential impact of the chemical cocktails with which we surround ourselves in the workplace and in the home. Multiple-chemical sensitivity was a buzz-phrase back in the early 1990s and filled many a column inch in trade magazines such as Chemical & Engineering News (C&EN) and the now-defunct Chemistry in Britain. I’ve still got the pre-PDF “cuttings” mouldering away in a filing cabinet somewhere. But, this syndrome doesn’t seem to feature much in the trade or any other media these days, I suspect its clinical significance like so many other nebulous disorders simply didn’t stand up to close scrutiny. There are many people who will likely disagree, and certainly medicine is far from perfect, but the assumption intrinsic in MCS is that synthetic = bad, which really isn’t the case.
However, Dimosthenis Sarigiannis and colleagues at the European Commission – Joint Research Centre, at the Institute for Health and Consumer Protection, in Ispra, Italy, seem keen to resurrect the notion that mixtures of chemicals are somehow more worrying than a single chemical acting alone.
Writing in the International Journal of Risk Assessment and Management, they assert how current risk assessments address compounds individually whereas real-life human exposure is to mixtures of chemicals present in the environment, the workplace, or consumer products. They suggest that a more connected approach to chemical risk assessment is needed.
Such an approach would combine information from environmental fate analysis, epidemiological data and toxicokinetic models to help us estimate internal exposure. This information might also be coupled to gene expression profiles to provide a signature of exposure to whole classes of toxic compounds so that we might derive a biologically based dose-response estimate. Such an approach will take into account the non-linear relationship between risk and exposure to mixtures of toxic compounds, the team explains.
The team concedes that any such model of risk-exposure will need a large data set to ensure that its predictions are statistically robust. And, I agree that we need to overhaul risk assessment in light of better understanding of how chemical mixtures affect gene expression, metabolism, and other biological processes. They also explain that a linear, additive approach to mixture toxicology is entirely outmoded given the latest evidence on non-additive effects. Again, I agree. This is not chemophobia this is rational assessment.
Sarigiannis, D., Gotti, A., Reale, G., & Marafante, E. (2009). Reflections on new directions for risk assessment of environmental chemical mixtures International Journal of Risk Assessment and Management, 13 (3/4) DOI: 10.1504/IJRAM.2009.030697
“Double on the contrary. MCS is not recognised by the scientific community.”
First, many of these same organizations did not recognize allergies, asthma, multiple sclerosis, and other illnesses as physiological. Just because these organizations did not recognize them did not mean they were not real. For a list of some of the organizations (including the AMA) that now recognize MCS:
http://mcs-america.org/index_files/MCSRecognition.htm
For a list of studies:
http://mcs-america.org/index_files/MCSScientificStudies.htm
Most important, Martin Pall’s research has produced a workable mechanism for how it starts and perpetuates. His theory has been published in Wiley’s General and Applied Toxicology, 6 Volume Set, 3rd Edition:
http://www.wiley.com/WileyCDA/WileyTitle/productCd-0470723270,descCd-tableOfContents.html
This year a research team identified clinical markers that confirm his theory:
http://www.resolv.org/nationalconversation/comments/attachments/MCS%20Tested%20-ScienceDirect.pdf
“Diagnosis seems to be driven by ideology, akin to the kind of ideaology that generates paranoia about vaccines and electromagnetic fields, rather than scientific medical assessment.”
The chemical industry has spawned a cottage industry specifically to fight recognition and study of the disease. Corporate ideologues have naturally aligned themselves with this industry, so it’s no wonder that there seems to be political ideologies involved. This means nothing when it comes to the actual science. Included in that list of studies are plenty of objective scientific assessments.
Your comment (and Emily’s) is one of the problems though: there are many assumptions about MCS sufferers that have little to do with the huge variety of people and experiences with it. My own experiences are completely at odds with the chemophobe-cum-sufferer characterizations out there, and they are similar to the majority of testimonies I’ve read and I’ve read many. I was having reactions, mainly migraine headaches long before I was able to associate them with chemicals. I followed the typical ritual of a migraine sufferer, embarking on a food elimination diet. It wasn’t until I realized that a lotion I used occasionally was one of the culprits and from there I realized the migraines were from fragrances. It was still long before I heard of MCS. When I read Pall’s work I was able to retroactively target formaldehyde exposures as the originator of the illness.
This is not a useless anecdote. Scientists, when faced with conditions that are completely unknown – think germ theory in the 19th century – need to leave everything on the table when searching for answers. In the cases of illnesses like allergies, MS, etc, this is even more important. What’s been done with MCS however, is that a public image campaign was launched early on to discredit the disease and too many people were eager to jump on the bandwagon long before any credible understanding could be found.
“If it were still a serious hot topic surely the likes of the Royal Society, American Chemical Society, and Royal Society of Chemistry would be on the defensive, I see no signs of that.”
Signs of this is all over the place. This is how it works:
http://www.tldp.com/issue/210/mcsundersi.htm
@brainfan Double on the contrary. MCS is not recognised by the scientific community. Diagnosis seems to be driven by ideology, akin to the kind of ideaology that generates paranoia about vaccines and electromagnetic fields, rather than scientific medical assessment. It isn’t even mentioned on the NHS website. MCS is not recognized by the American Academy of Allergy, Asthma, and Immunology, AMA, the California Medical Association, the American College of Physicians, or the International Society of Regulatory Toxicology and Pharmacology. The American Lung Association, EPA and US Consumer Product Safety Commission published on indoor air pollution that states that there is no definitive pathogenesis and suggests that symptoms self-diagnosed are probably allergies or psychosomatic. If it were still a serious hot topic surely the likes of the Royal Society, American Chemical Society, and Royal Society of Chemistry would be on the defensive, I see no signs of that.
Current bona fide scientific references please brainfad…
“But, this syndrome doesn’t seem to feature much in the trade or any other media these days, I suspect its clinical significance like so many other nebulous disorders simply didn’t stand up to close scrutiny.”
On the contrary. It’s close scrutiny in the face of deniers that results in understanding. I don’t know where you’ve been, but MCS is becoming more understood to the point where a mechanism for how it works has been theorized and subsequently confirmed in the real world. That theory has been published in a mainstream toxicology text, where the work belongs. There are reams of data that supports the physiological existence of this illness. This is how science works: it recognizes a problem and just because it is difficult to understand at first, true scientists persevere and find a solution. The converse brings us back to those who refused to wash their hands between surgical procedures because they did not recognize or understand the presence of germs.
@Emily Exactly and it’s usually the same people who equate both sides of those equations, isn’t it?
Manmade=dangerous is just the flipside of natural=safe. Fuzzy thinking, both ways.