The Scare-of-the-Month Club and Evil Chemicals
Question your assumptions
Here's are two old sayings. The first is from the 1960s:
The fact that I am paranoid does not disprove my belief that THEY are out to get me.
"We hold these truths to be self-evident . . . ." Most American readers over the age of 60 will recognize these immortal words from our very own Declaration of Independence.
Ironically the phrase could easily be inserted into much American writing, without changing the meaning. This is because we accept questionable premises as established facts, when they are anything but. This is especially true for health journalism. As Mark Twain famously said,
"Be careful about reading health books. You could die of a misprint."
Suppose that we see a scary headline proclaiming that a certain chemical causes cancer in experimental animals at extremely high concentrations, to which no human would ever be exposed. We could assume that this matters, and that we should be up in arms about it. Of course, that's what we're supposed to think. There's an old saying in the news business:
"If it bleeds, it leads."
We could embark on a crusade to eliminate all human exposure to said chemical, regardless of cost.
However there are a few problems with zero-tolerance policies regarding potentially harmful chemicals. Moreover there are issues with the zero tolerance concept itself, and with the related War-on-Whatever approach to solving social problems.
The question of scalability
Proportionality is a special case of scalability. It is often assumed that if we eliminate 90% of the human exposure to a questionable chemical, we'll also eliminate 90% of the adverse effects. However the assumption of proportionality is reasonable in some cases, but not in others.
Take lead poisoning. Chronic exposure to extremely low concentrations of some lead compounds has a measurably bad effect on the IQs of growing children. There's also a link between leaded fuel and crime.
America's Real Criminal Element: Lead
I think that it was wise to take the tetraethyl lead out of motor fuel in the US. However this decision was not a freebie. In the past, tetraethyl lead boosted the octane rating of petrol.
We pay a little more for octane-boosting additives, like MTBE and toluene, than we once did for tetraethyl lead. Motor fuel with a high octane rating is less likely to undergo pre-ignition or 'ping'. This prevents your car's engine from wearing out prematurely.
However MTBE has leaked from petrol storage tanks into the water table. Low concentrations of MTBE impart a bad taste to drinking water. This was a problem on the California side of the Lake Tahoe region.
Zinc poisoning is a different ball of wax. Why is that? It's because zinc, in contrast with lead, is an essential nutrient. We'd be dead without it.
The diet of some vegetarians is marginally deficient in zinc. For them, a little environmental zinc ion 'contamination' may actually be healthful! So much for scalability. Here's a famous quote from Paracelsus, a 16th Century physician:
"The dose makes the poison."
For essential minerals, the dose-response curve has a different shape than for non-essential minerals. Nevertheless Paracelsus' understanding of toxicology principles was deeper than that of most Greenies in North America, Europe, and Australia.
Are chemicals 'evil'?
Yes, this is a loaded question. However shrill rhetoric from our overrated opinion leaders sometimes short-circuits our better judgment, leading to black-and-white perspectives on scientific and technological issues. When we evaluate the relative risks of potentially harmful chemicals in our food and water, we need the ability to discern the various shades of gray.
There's a widespread belief that chemicals are always 'bad for you', in all quantities, and under all circumstances. Here's a counterexample: water. Yes, believe it or not, pure water is a chemical!
Here's a less-extreme version of this meme:
Synthetic chemicals are bad; natural chemicals are either good or less bad.
I say: Horse feathers! A basic principle of chemistry is that structure determines function. A non-chiral chemical found in a tropical rainforest plant is indistinguishable from the same chemical synthesized in a stainless steel vat. Still skeptical, are we?
I suggest that you drop whatever you're doing, and work towards a PhD in biochemistry. Then perform an experiment that has the potential to falsify your belief. Assuming that your experimental results pass muster, that you get published in a reputable scientific journal, and that others are able to replicate your work, your discovery will revolutionize science. You'll definitely get a Nobel Prize, and that will give you a bully pulpit to spread your message far and wide.
BPA (bisphenol A) has been in the news in recent years. BPA is a hormone disruptor found in certain plastics. There's much ongoing research on its actual and potential adverse impacts on human health. Some lines of inquiry are preliminary. Although these BPA studies are scientifically valid, the adverse effects on experimental animals in most--but not all--of these studies were discernible only at higher concentrations than are typically found in humans.
A secondary consideration is that humans and other animals have differing albeit overlapping complements of liver enzymes. Hence the toxicity threshold of a given chemical can vary from one species to the next.
Here's an example. An acquaintance of mine had a dog, who found and ate some unsecured chocolate. The theobromine in the chocolate was fatal for the dog.
BPA is an occupational health issue for people who work in the plastics industry. Moreover scalability was not an issue in a MINORITY of BPA studies; low concentrations had measurably bad effects.
Canada and the EU have outlawed baby bottles made from BPA-containing plastic. Here are four considerations that may have entered into that decision:
1. a chemical that has some known adverse effects at concentrations to which human are often exposed;
2. as compared with adults, an age group that is more vulnerable to numerous environmental risks;
3. higher exposure than most adults to the chemical in question;
4. the existence of glass baby bottles, a safe inexpensive alternative to the plastic ones.
The BPA decision on the part of Canada and the EU was a no-regrets policy.
Here's a link to Ren Chin's hub about plastics that contain BPA:
Plastic Numbers to Avoid - BPA Numbers.
BPA-containing plastic is also used to coat the inside of cans that contain food. This creates an interesting trade-off in the case of acidic foods, like pineapple. In an ordinary tin can, the acid will dissolve some of the tin, which passes into the food. High concentrations of tin salts are not particularly healthful.
Plastic-coated cans solve that particular problem, but they substitute a BPA problem to replace the old one. Which are less harmful: plastic-coated cans or old-fashioned tin cans? The jury is still out on that question. Of course, people who have sufficient time can cook their meals from fresh ingredients, and solve both problems.
Hundred-dollar peanut butter?
Let's look at carcinogens, chemicals that increase cancer risk. Stories about carcinogens keep surfacing in the infotainment media. However carcinogens in 'natural foods' don't get nearly as much press as the man-made ones. Milligram for milligram, Aflatoxins are among the most potent carcinogens known. They are synthesized by Aspergillus fungi. Aflatoxins are found in corn, peanuts, soybeans; and in some other crops that have been improperly stored after harvest.
Excess soil moisture can also contribute to Aspergillus flavus growth on peanuts, and to Aflatoxin concentrations inside the peanuts. Over the years, Agribusiness has been successful in gradually decreasing the concentrations of Aflatoxins in peanut butter. We can chalk that up to advances in technology, to the reasonable fear of lawsuits, and to the equally reasonable fear of bad publicity in Consumer Reports.
We could decrease the concentrations of Aflatoxins in peanuts even more, but it wouldn't be cheap. We could grow each peanut plant in its own earthenware pot, in its own little greenhouse. Each individual peanut plant would receive the right of water from a microprocessor-controlled irrigation system that measures soil moisture; so this critical variable is within the optimal range at all times.
A camera could monitor each peanut plant through all the stages of its growth. When the conditions are deemed to be optimal for harvesting of an individual peanut plant, a farm worker would be notified, and he would race to the scene. The peanuts from that particular plant would be put into a dehumidified truck that's always at the correct temperature. Then the farm worker would race to the next peanut alarm.
When the truck is full, off it goes to the roasting and grinding facility. We're talking state-of-the-art, Just-In-Time Inventory here.
Would you be willing to pay $100 for a jar of ultra-low-Aflatoxin peanut butter? Why not save $95 and buy your PB in a supermarket? You could use some of the money saved on your PB purchase to eat a serving of broccoli with every supper. Broccoli contains an anti carcinogen, sulforaphane. Assuming that your food budget is tight, and that you're craving PB, which option would decrease your cancer risk more? I'll go out on a limb, and say that the broccoli would more than cancel out the carcinogenicity of the minuscule amount of Aflatoxin in the PB.
In the meantime, if I were concerned about Aflatoxin in peanuts, I'd stick to peanut butter from the large manufacturers. Consumer Reports is not going to blow the whistle on a small organic peanut farm, which is a little behind the times with respect to food safety technology.
In terms of the Aflatoxin exposure risk, natural foods co-ops and health food stores are probably less safe sources of peanut butter, even if it is organic.
How does one think rationally about chemical risks?
Our Aflatoxin example illustrates an important idea: Zero risk is attainable only at infinite cost. Rational people need to put a price tag on mitigating each chemical or food risk. That price tag should reflect the actual magnitude of the risk, as well as the efficacy of the proposed remedy. How much bang for the buck would we get for the proposed mitigation strategy?
Of course, this is what our government claims to be doing. Unfortunately, there are often hidden agendas at play. Some political leaders claim that Anthropogenic Global Warming is the mother of all environmental risks.
Unfortunately for them, the available evidence is overwhelmingly against the Gorebull Warming superstition. Moreover the evidence for massive climate fraud is beyond reasonable doubt.
The late physicist, Hal Lewis, wrote an outstanding book, Technological Risk. One of Lewis' points was that the magnitude of a typical risk is inversely proportional to the scariness and frequency of headlines about it. There are obvious exceptions to Lewis' rule of thumb: obesity, alcoholism, and smoking.
There's also an interesting wrinkle on the risks of smoking. Preliminary evidence suggests that nicotine, which is found in tobacco leaves, can decrease the likelihood, or at least delay the onset of Parkinson's Disease. Here's a LINK to an article about that at webmd.com. Tobacco is not inherently 'evil', although it is definitely not my cup of tea.
If you're at risk for this debilitating disease, please do not take up smoking. It's less risky to self-medicate with Swedish Snus instead.
Anyone who aspires to save the world from itself should read Technological Risk first. Lewis goes into considerable detail about several well-publicized risks. Even though the book is not current on the latest research, the principles are still valid.
My main criticism of Technological Risk is that Lewis' discussion of discounting the future needs more elaboration.
There are two types of mistakes that we can make, regarding the mitigation of risks from harmful chemicals in food, or in the environment. A Type 1 Error is a failure to take appropriate action in a timely fashion. It can kill people in an obvious way.
Some Type 2 Errors involve throwing money at false alarms. Another Type 2 Error is a disproportionate response to a legitimate concern. When we squander scarce resources in these ways, there's less money to spend on appropriate responses to real problems. Thus Type 2 mistakes can kill people indirectly. Type 1 Errors are not more 'evil' than Type 2 Errors.
The Precautionary Principle, a Type 2 approach, is essentially a euphemism for panic as public policy. Here's a trenchant comment from the late author of Jurassic Park, Michael Crichton:
"The 'precautionary principle,' properly applied, forbids the precautionary principle. It is self-contradictory. The precautionary principle therefore cannot be spoken of in terms that are too harsh."
Here's a parting thought from Jennifer Marohasy, a leading Australian advocate for evidence-based environmental policy:
"If you can't measure it, you can't manage it."
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