Viewpoint: Chemophobia epidemic—Fanning fears about trace chemicals obscures real risks and ‘damages public health’

When is a chemical dangerous?

This is not a question we consciously ask ourselves much, but in fact, we interrogate the world and our safety unconsciously dozens of time each day about it. Is our child’s plastic sippy cup made with dangerous chemicals? Does the cleaner we are using on our car give off dangerous fumes? What about the spray to kill dandelions?

It’s also an issue constantly in the headlines. Earlier this week (October 24) an article appeared in the JAMA [Journal of America Medical Association] Internal Medicine journal claiming that people surveyed who primarily ate organic food were less likely to contract cancer—and it postulated that pesticide residues in conventional might be the causal factor. [more on that study below]

How do people assess hazard and risk? How safe is safe?

Media perceptions and government regulations are often shaped by a fervor fed by misconceptions about the widespread dangers of common chemicals. Consider the word “pesticide.” Sounds scary. After all, synthetic and natural pesticides kill unwanted pests such as insects, weeds, fungi and rodents.

risk hazard sharks minimized

But advocacy groups, many hostile to conventional agriculture, mostly refer to pesticides pejoratively, assuming anything that can kill an insect or weed can also do a lot of damage to humans exposed to trace residues. This is almost never true. In fact, it is not even possible for some pesticides to harm humans. For example, it’s biologically impossible for Bt bacterium proteins that are found in soil and plant leaves worldwide and which are sprayed widely by organic farmers to kill certain insects and are bioengineered into insect-resistant seeds to harm humans or animals because mammals do not have the same receptors or gut conditions as insects. But that doesn’t stop the hysteria or misrepresentations from advocacy groups who claim food grown from Bt seeds are chemically harmful to humans (while irrationally exonerating Bt spraying by organic farmers).

Pesticides are regularly, and irrationally, blamed for all sorts of problems—from environmental pollution to hormonal disruption to cancer. One prime example? Glyphosate.

Just this week, an appellate judge upheld a jury verdict blaming the herbicide found in Monsanto’s Roundup® and generic formulations for a California groundskeeper’s cancer. As the judge noted, the ruling came despite hundreds of reviews and studies, most by government regulatory oversight agencies and independent scientists, that has found the popular weed killer to be safe as used. The judge cut the jury’s punitive damage award by 84% to $39 million after hinting during a prior hearing that she was considering throwing out the verdict altogether because of a lack of independent research linking glyphosate to cancer.

The verdict turned on a June 2015 evaluation by the International Agency for Research on Cancer (IARC) that glyphosate was “probably carcinogenic to humans.” It was not a finding of “risk” but of “hazard”—and did not take into account exposure. IARC put glyphosate in the same category as coffee and salted fish. It was deemed less possibly carcinogenic than alcohol, which is very hazardous and can lead to cancer—if you are exposed to (consume) extraordinary amounts of it. The IARC evaluation was also plagued by conflict of-interest charges and allegations uncovered during a Reuters investigation that data was manipulated or left out. Also, it emerged during the trial that Christopher Portier, the chief IARC investigator, had negotiated to be a well-paid consultant ($160,000 in disclosed fees) before the hazard decision was even announced.

Chemophobia may lead to real risks

The fact is that almost all chemicals we encounter on a regular basis have undergone reviews of one kind or another and are safe as used. Yet people still believe that somehow one government agency or another “missed something” or that it’s in cahoots with “big business” and has fudged the safety data.

An illusion also has developed that chemicals can be divided into categories of “safe” versus “unsafe.” But any substance, even food and vitamins, can be harmful if we consume too much of it. Safety is relative, depending on the frequency, duration and magnitude of exposure.

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To put into context how askew this debate has gone, let’s look at the supposed risk that pesticides cause pediatric cancer. No issue could be more emotionally charged.

Warning Pesticides

study published in August 2018 in The Lancet Oncology examined the incidence of pediatric cancer from 1991 to 2010. It was a gigantic study that included 1.3 billion person-years. (One “person-year” is an epidemiological term that refers to one person being studied for a period of one year.) The study found cancer rates have stabilized over the past decade after minimal increases of 1 percent in the two previous decades. As for the impact of pesticides, in an accompanying commentary, Belgian cancer epidemiologist Philippe Autier wrote:

In 2014, the quantities of pesticide sales per capita were about three times greater in Spain, Italy, and France than in Sweden or the UK. If increasing cancer incidence trends were due to pesticides, dissimilarities in incidence trends for leukemia and lymphoma would be expected between European regions, which was not the case.

Put another way, if pesticides were a serious driver of pediatric cancer, then countries that use more pesticides are likely to have more cases of pediatric cancer. But they don’t. Therefore, pesticides probably do not cause pediatric cancer—which is what almost all scientists believe, rejecting hysteria anti-trace pesticide campaigns by activist organizations such as the Environmental Working Group and its infamous Dirty Dozen campaign.

Related article:  Viewpoint: If farmers want the public's trust, they should change how they talk to consumers

More fears, stirred by headlines in newspapers and media sites around the world, emerged this week with the publication of a French study suggesting that trace pesticides in conventional food might cause cancer —at least that’s what the authors, who propose that people might consider switching to organic food, claim. They posed the question: “What is the association between an organic food–based diet (ie, a diet less likely to contain pesticide residues) and cancer risk?” Their conclusion: One possible explanation for the negative association between organic food consumption and cancer risk is that the prohibition of pesticide use in organic production methods results in lower contamination levels. The results suggest, they said, that that “attention should now turn to the potential chronic effects of low-dose pesticide residue exposure from diet as well as potential cocktail effects at the general population level.”

While some scientists praised the study for raising a yellow flag about pesticide residues, many independent epidemiologists and statisticians eviscerated it. It was a muddle based on self-reporting and only of French residents who polls show are enraptured by organic food and hostile to many modern agricultural practices that include synthetic fertilizers and pesticides. Only 2% of the respondents got cancer, which itself is an extraordinary small number.

Organic eaters in the study were more likely to be more affluent (36% likely to be less poor), have a college degree, eat more vegetables and less processed meat, have a healthier diet overall and they are less likely to be overweight and were more active––confounding facts. The authors claimed they adjusted for some factors but not all and their methodology for adjusting is not transparent.

Oddly, the authors made the claim that the link to cancer for those in poverty was not causal while it was for eating organic food, what seems like an arbitrary conclusion. In one startling paragraph, the authors note that the correlation to cancer did not hold for younger adults, never or current smokers, people who eat healthy food, and, remarkably, for all men.

Screen Shot at PM

What a hodgepodge of questionable science! Correlation studies are problematic at best with authors frequently cherry-picking associations that fit pre-conceived notions (it should be noted that the lead author in the study is a well known proponent of organic food) and rejecting or not even considering correlations that might confound the results. According to Tom Sanders, professor emeritus of Nutrition and Dietetics at King’s College London:

This an observational study, not a controlled trial. The participants who reported eating organic food most frequently were more likely to be non-smokers, had a lower body mass index (less obesity) and drank less alcohol, all factors that would be expected to result in fewer cases of cancer in this group. Their conclusion, that promoting organic food in the general population could be a promising cancer preventive strategy, is overblown.

[Editor’s note: Read other scientists’ analyses of this study at the UK Science Media Centre]

This is yet one more study that appears to have been designed to confirm a preconceived viewpoint.

The bottom line is that more research is necessary to uncover the causes of cancer but there remains no persuasive evidence that trace residues are a key driver. The public and advocacy group obsession with the alleged dangers of trace chemicals found in common usage is unhealthy. Serious health challenges need to be forcefully confronted, but the resources devoted to challenging and removing relatively innocuous chemicals in exchange for substitutes––usually substances that have often not been scrutinized as much as the chemicals they would replace and thus confer an illusion of safety––divert us from addressing known health risks. This chemophobia can result in the opposite of what was intended: a decrease rather than an increase in public health.

Jon Entine is a freelance journalist, author of “Scared to Death: How Chemophobia Threatens Public Health” and other books, and founder and executive director of the Genetic Literacy Project. Follow him on Twitter @JonEntine

7 thoughts on “Viewpoint: Chemophobia epidemic—Fanning fears about trace chemicals obscures real risks and ‘damages public health’”

  1. At last look, the web page for the Chemical Abstract Society ( claims to have 144 million unique organic and inorganic chemical substances in their database. That in addition to the simple observation that it takes at least 14 years for a chemical substance to be banned because of toxicological concerns should cause everyone to have some level of Chemophobia. Who should one believe a chemical is safe? Our senators and congress, which spend endless hours with lobbyists from industries? Should we believe the companies who make billions of dollars a year selling the chemical/product? How about listening to your doctor who gets more calls from industry than the government representatives? What about our current regulatory agencies EPA, FDA … etc., who appear to be in a pro-industry not pro-safety/consumer mode? Can you believe all of the non-profit organizations that tell you a chemical is toxic and if you send them money they will keep you informed? How about searching the Internet, only to find hundreds/thousands of stories from industry, government, non-profits and academics … saying it is safe and not safe at the same time? Based on the current state of affairs, I say Chemophobia is probably a good thing … minimize your exposure to as many chemicals as possible, know where your food comes from, be aware of who is telling you something is OK or not and understand what is in it for them. The time has come for each of us to be responsible for what we expose ourselves and our families to … make the best choice for you and your family … in the end no one other than you will pay the consequences – everyone else will have taken your money and will be long gone! Joe – toxicologist for 42 yrs

    • Exactly, despite of who it is, there is always an interest and an agenda behind the opinion. Whether it’s paid or genuine concern for humanity is the million dollar q.

    • Lots of questions there, joe. Not many facts, tho. You of course are free to consume, or not consume, whatever you want. Trouble is, activists insist on making those choices for the rest of us by injecting their irrational fears into public policy-making. If chemophobes want to be science deniers, fine. Don’t penalize the rest of us.

  2. Chronic/delayed health effects of various exposures are hard to tease out and require massive public health studies. Also exposure during tissue development (in-utero and childhood) may have massive effects not found later. Also worker exposures may be many times over those of consumers.

    Even for the big old culprits we know about such as mercury, lead, asbestos, benzene etc. it took tens of years to reach consensus on harm during which people were exposed. Btw funding large studies that figure out things like “lead is bad for brain development” is one of the things only governments do. And even so few of the do and do too little of it.

    Except for a few cases these harmful chemicals are useful, otherwise they would not be there. Often safer alternatives can be found. But the industry often prefers to complain instead only to come up with them when pressed by regulation or public opinion. After much complaining lead in gasoline was phased out without causing the collapse of the economy.

    Am I to believe that the all the science on hazard / risk is done on the millions of chemicals we use? Someone could have said the same in the 70’s before the health effects of lead and mercury made us take them out. And if the science is still evolving why would I put up with any risk to my kids, no matter how small? If they cost about the same and work why not prefer products that are safer? Sometimes even pay a bit more.

    It is not chemophobia. The fact that I don’t eat every mushroom in the forest, even though some may be safe and nutritious, does not make me a fungophobic. We normally avoid things we don’t know for sure are safe. We’re just beginning to apply this rule to man made chemicals. People are of course far from precise or scientific and there are some over reactions. But why be patronizing to people who want their families to be safe?

  3. All good points, it’s nice to see that other people are thinking about this stuff and looking at it from different points of view … if anything is to happen it will be because we all come together and do something about the problem. Cornfed, you make several good points … I didn’t include a lot of info, but not all chemicals have a lot of data questioning human and environmental safety. Unfortunately this is one of my concerns – there are literally 144 million chemicals all around us and we have no idea what the impact (if any) there is to life. Who is responsible for making sure we are safe? Nicholai and achbm make good points too … do we fund academia to conduct safety studies, do we let the government do it … do we do studies at independent groups and get industry to pay for the studies? I also agree with not penalizing everyone or forcing opinions on individuals, but what do you do when the problem becomes so big that it cannot be contained and someone else’s choice causes damage to others? Achbm, also made me think of a story on lead I wrote for Hawaii … … the inventor of leaded gasoline was convenience that his invention was the answer to a problem (which it was) and that the chemical he developed didn’t cause the death of others – even up to the point of making himself sick by using it? We all have strong beliefs, but at some point we have to look at the facts … we knew that lead was a problem, but it was still used in gas for about 70 years and now it is in hundreds of products from lead pipes to simple food coloring. There is no simple answer, but at least we all started thinking about it which hopefully is the first step. Stay safe, Joe

  4. “people still believe that somehow one government agency or another “missed something” or that it’s in cahoots with “big business” and has fudged the safety data.”

    Yes, how silly of them!
    “the tobacco industry used its connections within government to assure a weak bill and a weak warning label (Brandt 2007). The wording of the label, “Caution: Cigarette Smoking May Be Hazardous to Your Health,” contrasts sharply with the certainty of the 1964 report’s conclusion on smoking and lung cancer.”

    Etcetera. Just one example of many that could be cited.

  5. Chemophobia is an issue on the rise as we advance further in society and has been long instilled in my life as I have had to choose daily whether to ignore the possible side effects vs the possible risks of every day products. Joe DiNardo, you have several great points. The fact is that as humans living in a modern society we are exposed to millions of chemicals daily and as individuals we must assess whether we feel they cause any harm.
    I had a phobia of BPA (bisphenol A) several years ago. BPA is a substance that is used in plastics and has been reported as an endocrine disrupter, or on a simplified explanation, something that could skew hormone levels in healthy individuals. I stopped consuming anything that came from plastic packaging. I tried to persuade others to do the same. I proceeded with this lifestyle for one year until I asked myself: “what do we truly know?” In 2007 a study was reported on PUBMED (Chemosphere. 2007 Jan;66(6):1160-4. Epub 2006 Aug 14.) that spoke of the possible effects of this chemical on embryo and postnatal development. They have conclusive evidence that this chemical is higher in the maternal blood serum when compared to healthy women. Other studies report high levels of BPA in the blood and urine samples of those that consume it. However, does that have a negative effect on the development of an embryo? Or could it have the possibility of causing systemic dysfunction of the endocrine or apocrine systems? In one study, it was reported “The obtained BPA data indicate major species differences in the disposition of bisphenol A “ (Chem Res Toxicol. 2002 Oct;15(10):1281-7.) Another great point; species specific genetics are allowing for differences that deem this chemical difficult to study. Therefore, we are at a loss, since we cannot possibly inject humans with a possible toxic potentially harmful chemical on a basis great enough to find conclusive results.

    I bring up these cited articles because it the same problem we are having with the chemicals we encounter daily. Are we at a risk?; of course. However how high is this risk? When do we as individuals being to forfeit things we like or find convenient for possible threats? Unfortunately there is not one answer.
    Ethically, we all want to do what is right for the most amount of people and in doing so we want the best possible outcome for ourselves. Again, Joe DiNardo you articulated this point perfectly: we must assess what we expose ourselves to, some which may be out of our control, and make the best decision we can with the information we have. The chemophobia is only going to increase in some people. We are developing new treatments, medications, products, environmental agents, etc. by astronomical numbers daily. Unfortunately, we need to utilize them before we can start a 50-year study on them finding potential risks vs benefits.

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