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|#800 -- The Chemical Wars, Part 3, September 16, 2004|
by Peter Montague
[Continuing: We have been describing the philosophy of environmental regulation in the U.S. Basically, it is a "prove harm" system -- anything goes until someone can "line up the dead bodies" and prove that significant harm is occurring. When that happens, which is rare, then a multi-year, or multi-decade, battle begins in which underfunded and understaffed government regulators bargain with a phalanx of corporate lawyers and scientists-for-hire. Eventually they hammer out a compromise between public health and corporate purposes. The compromise becomes an enforceable regulation --until one corporation or another decides to mount a challenge and the dance begins anew.
The "prove harm" system rests on three assumptions: (1) Humans can determine the "assimilative capacity" of every population of humans and animals and every ecosystem on Earth -- the capacity to absorb damage without suffering permanent, serious harm. (2) Once the "assimilative capacity" of a river, or a population of humans or birds, has been determined, we will set regulatory controls to keep the harm within "acceptable" limits; and (3) We already know which substances and activities are harmful or, in the case of activities we never suspected were harmful, we will be warned of possible dangers by traumatic but sublethal shocks.
Obviously the system really hinges on assumption #1 -- that we can determine the "assimilative capacity" of an ecosystem, or of a population of polar bears or humans. For this purpose, a special technique has been developed called "risk assessment." Risk assessment is the linchpin of the "prove harm" regulatory system, and the main intellectual armor of industrial polluters. But this emperor is wearing no clothes. Let's take a look.]
Of course there's nothing wrong with trying to assess risks. We all do it every day. But there's an important difference between our own personal risk assessments and corporate/governmental risk assessments.
When we assess risk in our own lives, (a) we examine risks that we ourselves are willing to take; (b) we compare our options; and (c) we use all available information; and (d) we weigh not only the risks we face but also the benefits. For example, we might ask ourselves, "Can I just dash across this street in the middle of the block, or, given the shoes I'm wearing and the arthritis in my left knee, should I walk to the corner and cross with the light? Is saving a minute or two worth the risk of being hit by a truck?" We compare risks and benefits, we assess our alternatives, we consider all the available information, and we weigh the risks we ourselves are willing to take.
In contrast, corporate risk assessors almost always (a) assess the dangers of a single pre-determined option, and (b) assess dangers that they intend to impose on others, usually without their informed consent; and (c) examine only the scientifically-proven evidence, ignoring other kinds of information such as historical precedents, worker knowledge, and community preferences; and (d) ignore the benefits (or lack of them) to those who will be enduring the dangers. Basically, the main use of corporate/governmental risk assessment is to establish how much damage corporations and governments can get away with and to label that damage "acceptable."
Typical questions that corporate/governmental risk assessments answer would include, How much dioxin can aluminum smelters discharge into the Columbia River basin without thinning the Bald Eagle population to extinction? How many trout can families along Lake Michigan eat each month before their children's IQs are diminished 5 points? How much benzene can we maintain in the air of this factory without killing more than 1 in every 10,000 workers? Will this urban trash incinerator kill no more than one in each million citizens who breathe its fumes?
Risk assessment serves corporate purposes because it involves large quantities of scientific data, all of it subject to limitations and uncertainties that can be disputed forever without resolution. Where data are lacking or disputed, assumptions and judgments must be substituted for facts. The National Academy of Sciences put it politely when it said, "Risk assessment techniques are highly speculative, and almost all rely on multiple assumptions of fact -- some of which are entirely untestable." In 1983 the National Academy identified at least 50 points during the course of a cancer risk assessment where choices had to be made on the basis of professional judgment, not science. Corporate scientists-for-hire can select and manipulate the data and choose particular assumptions (often silently), allowing them to reach almost any conclusion they set out to reach yet still package it as "science" even though the conclusion is based on judgment and is not in any way reproducible.
Risk assessment provides corporations other major benefits as well. Because risks are expressed mathematically (the probability of x occurring during y years of exposure to chemical z), troublesome questions of right and wrong cannot arise, and most of the public is left out of the process. Thus risk assessment gives corporate goals a patina of "sound science," prevents ethical considerations from muddying the debate, and keeps the affected citizens locked out of the discussion.
Risk assessment now guides all environmental management, not merely the control of chemicals. Before cutting new roads into a national forest, the government completes a risk assessment to decide how many roads would decimate the bear population. Ocean fisheries are managed by risk assessment to determine the "maximum sustainable yield" of fish. Risk assessment determines allowable drug residues in beef, allowable pesticide residues in food, allowable withdrawals of water from rivers and aquifers, allowable contamination of drinking water, limits on the discharge of particulates and toxic chemicals from coal-fired power plants, auto emission limits, livestock grazing allotments on arid lands, allowable harvests of endangered species, fishing and hunting quotas, workplace exposure limits, radiation limits in medical settings, cleanup standards for contaminated sites, and on and on.
Risk assessment is so fundamental to the "growth and rapid innovation" culture that the technique is now taught at most large colleges and universities. There are several scholarly journals devoted to it. Many books have been written on the subject, including several by the National Academy of Sciences. The federal government sponsors research to elaborate and refine risk assessment techniques, and it trains risk assessors in places like Mexico and the Ukraine, intending to "harmonize" the response to corporate harms world-wide. Risk assessment research institutes at places like Harvard are generously funded by important corporate risk-makers like Monsanto and Dow, and the work of these institutes is injected directly into federal "risk policy." Professional societies of risk assessors meet each year in resort locations to swap war stories and share their latest techniques. Assessing risks has become a major industry unto itself. It is no exaggeration to say that the modern industrial system with its culture of "rapid innovation at any cost" could not maintain its present course without risk assessors to run interference.
In the last decade, however, risk assessment has come under withering criticism from at least a dozen perspectives:
1) Because of genetic makeup, individuals differ markedly in their susceptibility to poisons. Some people are far more sensitive than others. For example, some people cough and wheeze when they walk down the detergent aisle at the grocery store; others don't. Furthermore, many people suffer from chronic conditions (asthma, diabetes, etc.), so risk assessments cannot reasonably assume, as they typically do, that only healthy young adults are exposed.
2) Risk assessors try to account for human variability by applying a "safety factor" of 10 to their numerical estimate of risk. But such a number has little to do with science. Safety factors are often little more than guesses. Why not a factor of 11 or 17 instead of 10? Even calling it a "safety" factor is misleading because who can say it offers safety?
3) Risk assessments of chemicals are conducted on single chemicals, but in the real world we are all exposed to mixtures of chemicals day in and day out. Furthermore, many studies have now shown that harmless amounts of individual chemicals, in combination, can add up to a harmful dose. The health effects of mixtures are far too complex for science to sort out, yet mixtures are what we encounter in our daily lives, so testing single chemicals is misleading and often beside the point. Corporate scientists-for-hire may pretend that, with sufficient testing, the problem of mixtures can be mastered. But when asked where the resources will come from to test all possible combinations of even 1000 chemicals, they grow silent. There are 41 billion possible combinations of 1000 chemicals taken in groups of 4. Even if we could test a million combinations a year, which we can't, it would take 41,000 years to complete such a battery of tests.
4) Some chemicals are only biologically active during a brief period of time (a "window of vulnerability") in the development of an organism, so toxicity must be tested during those exact times.[6,7,8,9,10] Chemicals tested during other times will appear to be less potent or even inert.
5) In the case of some hormone-disrupting chemicals, low doses can cause greater endocrine disruption than high doses. More than 100 studies have now confirmed that this phenomenon is real. This seems to happen because the hormone system is active at low doses but becomes overwhelmed and stops responding at higher doses. Traditionally, chemicals have been tested at the highest doses that laboratory animals could tolerate, but now we know that high-dose tests may miss important toxic effects that only occur at low doses. Many of the high-dose tests that have been completed to date (and upon which federal regulations are based) are of very limited value from a public health perspective and need to be re-done at much lower doses.
6) We now know that cells respond differently to chemicals, depending on their prior history of exposure.[12,13] In addition, whole organisms (mice, humans) exhibit similar behavior: response to a chemical is strongly conditioned by prior exposure. For example, a person who smokes a cigarette for the first time reacts with lightheadedness and perhaps nausea but a habituated smoker develops a craving for cigarette smoke and feels sick without it. Furthermore, after a heavy smoker quits smoking, he or she will be "sensitized" to second-hand smoke thereafter, reacting to it much more powerfully than a person who has never smoked. Thus individual history of exposure to a chemical can dramatically affect response. This important phenomenon is not taken into account in the toxicity tests that underlie chemical risk assessments.
7) It has now been established that cells respond differently to pulsed exposures to some chemicals, compared to continuous exposures. Thus a pattern of repeated exposures interrupted by regular intervals of non-exposure elicits a different response compared to cells continuously exposed.[14,15] "For example, when animals respond to gonadotropin-releasing hormone, the pulse frequency of stimulation is more important than the average level of the hormone."
8) Medical understanding of the role of inflammation in disease is now changing substantially. Inflammation is a sign that the immune system has been incited, and animals (or humans) with inflammation react differently to chemical exposures than animals without inflammation.
9) We now know that many dose-response relationships are not linear. Indeed, the shape of dose-response curves is the subject of an extensive body of contentious literature, yet risk assessors continue to rely most often on the simplifying assumption of linearity. This simplifying assumption makes many risk assessments possible but it may also make them wrong.
10) Thousands of potentially important biochemical reactions are ignored during risk assessments. Current federal protocols for examining the tissues of experimental animals were developed before the advent of biochemistry and molecular biology. After animals are dosed and then killed for tissue analysis, their organs are examined visually for gross damage, but microscopic examination of the organs is not typically required -- much less the sophisticated analyses made possible by modern biochemistry and molecular biology. Animal testing is decades behind current biology, and will likely remain so for economic reasons. Thorough examination of dosed animals would be far more expensive than the simple examinations that are standard today (and which already cost in the range of $20,000 to $100,000 per test).
Even when animal tissues are examined under a microscope, not all tissue types are examined. All organs are composed of various types of cells, and each type would need to be examined to claim that a thorough investigation had been conducted, but this is not done.
Thus thousands of distinct biochemical mechanisms are not examined, because no one requires them to be (to keep costs down). Cognition, behavior, fertility, disease resistance, male reproduction, chronic neurotoxicity, immune alteration and hormone function (critical to hundreds of biochemical systems) are all ignored in typical risk assessments.
In sum, thousands of potential injuries are missed by typical gross visual (and occasional microscopic) examinations in animal toxicity tests.
11) The vulnerable period of development is not tested. With rare exceptions, the period of greatest vulnerability (corresponding to the human period of life from conception through age 18) is not tested in laboratory animals. Adult animals are tested. In addition, effects on second and third generations are not typically looked for.
12) The commercial forms of chemicals tested in the laboratory may bear little resemblance to chemicals of the same name found in environmental food chains. Depending on source of exposure, pathway through the food chain, and weathering effects, chemicals measured in humans or other animals can have distinctly different characteristics from "pure" commercial forms of chemicals, meaning that many risk assessments are conducted on chemical species that are not encountered in the real world.
It must be obvious that these shortcomings of risk assessment cannot be remedied because there simply aren't enough laboratories and enough money to take into account all the sources of variability listed above.
And if corporations and government agencies cannot systematically take these biological phenomena into account, they should acknowledge that their risk assessments are hardly more than window dressing, having little to do with reproducible science, intended mainly to mollify an apprehensive public.
[To be continued.]
Reprinted with permission from: Peter Montague, "The Chemical Wars," New Solutions Vol. 14, No. 1 (2004), pgs. 19-41.
 Mary O'Brien, Making Better Environmental Decisions; An Alternative to Risk Assessment (Cambridge, Mass.: MIT Press, 2000; ISBN 0-262-65053-3).
 Quoted in Anthony B. Miller and others, Environmental Epidemiology, Volume 1: Public Health and Hazardous Wastes (Washington, DC: National Academy of Sciences, 1991), pg. 45.
 United States General Accounting Office, Chemical Risk Assessment; Selected Federal Agencies' Procedures, Assumptions, and Policies [GAO-01-810] (Washington, D.C.: United States General Accounting Office, August, 2001), pg. 31.
 A major study of risk assessment was conducted by 11 European governments during the period 1988-1990, and published by the Commission of the European Communities under the title Benchmark Exercise in Major Hazard Analysis in 1991. The 11 governments (Netherlands; Greece; Great Britain; Denmark; Italy; Germany; France; Belgium; Spain; Finland; and Luxembourg) established teams of their best scientists and engineers and set them to work on a single problem: analyzing the accident hazards of a small ammonia storage plant. Private companies like Rohm & Haas, Solvay, Battelle, and Fiat contributed experts as well. The results were stunning: the 11 teams varied in their assessment of the hazards by a factor of 25,000. Analyzing the hazards of a single, small plant handling only one chemical, these world-class "risk experts" reached wildly different conclusions. For example, the individual risk at the "refrigerated storage site" was calculated by one group of experts to be one-in-400, but by another group of experts to be one-in-10-million. (Figure 3.5, pg. 58 of the Benchmark study.) See Commission of the European Communities, Benchmark Exercise on Major Hazard Analysis. 3 Volumes. (Luxembourg, Luxembourg: Commission of the European Communities, 1991).
 David O. Carpenter, Kathleen Arcaro, and David C. Spink, "Understanding the Human Health Effects of Chemical Mixtures," Environmental Health Perspectives Vol. 110 Supplement 1 (February, 2002) pgs. 25-42.
 Beverly S. Rubin, Mary K. Murray, David A. Damassa, Joan C. King, and Ana M. Soto, "Perinatal Exposure to Low Doses of Bisphenol A Affects Body Weight, Patterns of Estrous Cyclicity, and Plasma LH Levels," Environmental Health Perspectives Vol. 109, No. 7 (July 2001), pgs. 675-680.
 K.S. Landreth, "Critical windows in development of the rodent immune system," Human and Experimental Toxicology Vol. 21, Nos. 9-10 (Sep-Oct, 2002), pgs.493-498;
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 Erik Baatrup and Mette Junge, "Antiandrogenic Pesticides Disrupt Sexual Characteristics in the Adult Male Guppy (Poecilia reticulata)," Environmental Health Perspectives Vol. 109, No. 10 (October 2001), pgs. 1063-1070.
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 M.S. Berrill, S. Bertram, B. Pauli, D. Coulson, M. Kolohon, and D. Ostrander, "Comparative sensitivity of amphibian tadpoles to single and pulsed exposures of the forest-use insecticide fenitrothion," Environmental Toxicology and Chemistry, Vol. 14, No. 6 (1995), pgs. 1011-1018;
 R.B. Naddy, K.A. Johnson, and S.J. Klaine, "Response of Daphnia magna to pulsed exposures of chlorpyrifos," Environmental Toxicology and Chemistry Vol. 19, No. 2 (2000), pgs. 423-431.
 P.E. Ganey and R.A. Roth, "Concurrent inflammation as a determinant of susceptibility to toxicity from xenobiotic agents," Toxicology Vol. 169, No. 3 (Dec 28, 2001), pgs. 195-208.
 U.S. Environmental Protection Agency, Health Effects Test Guidelines; OPPTS 870.4100 Chronic Toxicity [EPA 712-C-98-210] (Washington, D.C.: U.S. Environmental Protection Agency, 1998.)
 S.L. Schantz, J.J. Widholm, and D.C. Rice, "Effects of PCB Exposure on Neuropsychological Function in Children," Environmental Health Perspectives Vol. 111, No. 3 (March 2003), pgs. 357-376.