Despite the fact that a common concern with solving serious or even deadly environmental problems unites them, these actors in the decision making process commonly find that they cannot begin to agree on solutions. No sooner does the discussion begin than it appears that everyone is looking at the problem from a radically different perspective, especially as concerns the perception of risk. For fifteen years, my work as a local environmental activist has led me to the conclusion that this divergence of views is a logical result of an unresolvable conflict of economic interests: citizens simply want more protection than industry and government want to pay for. I also began to suspect that citizens, scientists, and policy makers were unable to communicate clearly because they are products of distinct subcultures and speak different languages.
While all of the above factors may be important, I have recently come to understand that much of the acrimonious disagreement that surrounds public participation discussions has a simpler origin. It involves the unacknowledged conflict between fundamentally different views of acceptable risk. I hope that by identifying this problem, it may become solvable.
For example, when discussing the health effects of the Chernobyl accident, a representative of the International Atomic Energy Agency (IAEA) insisted on using "deterministic" criteria (clinical evidence based upon nearly certain cause and effect relationships following immediately upon the accident).
The IAEA representative rejected "stochastic evidence" (cause and effect associations based upon probabilistic relationships occurring either shortly or long after the accident). He therefore dismissed all statistical epidemeological evidence of illness or death related to Chernobyl as unscientific.
Similarly, scientific consultants working for the Chlorine Chemistry Council of the Chemical Manufacturers Association sought to ensure that health assessments associated with chlor-organic compounds like pesticides, plastics, and dioxin are "scientifically grounded", a concept that they then defined as based upon a "full weight of evidence approach".
In practice, this approach resembles the clinical burden of proof demand made by the IAEA official. For example, when addressing the controversial U.S. Environmental Protection Agency (EPA) reassessment of dioxin, the Chlorine Council criticized the EPA for relying upon "animal data rather than available human data" and for using a model of human dioxin exposure "which has not been validated by experiment." Both the International Atomic Energy Agency and the Chlorine Chemistry Council spokesmen at the AAAS convention invoked the most stringent scientific criteria of proof of risk when evaluating risks associated with existing facilities or products.
Confusion entered into the discussion of health risk assessments at the AAAS meetings when there was a change in the level of scientific certainty demanded by participants from the scientific and policy making community. This was demonstrated by scientists who vehemently opposed a Greenpeace proposal to employ "precautionary" risk assessment criteria for chlor-organic compounds. (Chlor-organic compounds are chemical compounds with chlorine atoms attached to an organic molecular structure such as benzene or ethylene. Examples include many pesticides and plastics.) The Greenpeace proposal was the focus of the day long "World Without Chlorine" seminar. Greenpeace argues that chlor-organic compounds are too persistent in the environment and are too harmful to be permitted for use based solely upon statistical risk projections which extend permits to whole families of compounds whose characteristics vary widely. According to Greenpeace, such compounds should be subject to precautionary risk assessment. In other words they should be considered harmful until they are proven to be environmentally safe.
Opposing the Greenpeace proposal were industry scientists and many academics who prefer the present method of risk assessment. This method generally assumes that a chemical or substance is harmless unless proven harmful. They thus exhibited a willingness to accept an extraordinarily high level of uncertainty about the toxicity of new chemicals, nearly 100% uncertainty in the case of many of the more than one thousand new chemicals entering the market place yearly. This was a remarkable and confusing reversal of their position that toxicity assessments be based upon clinical evidence and that only such evidence should be used in policy making .
Such inconsistencies in establishing the ground rules for discussion of risk and the burden of proof for toxicity could be expected to disrupt communications between the concerned public on the one hand and scientists and policy makers on the other. Adding to the confusion, scientists and policy makers infrequently take the time to explain their disciplinary perspectives in general terms to the public. Even more rarely, if ever, do they discuss their assumptions concerning burden of proof. Consequently, members of the public often view the resulting changed expectations about the burden of proof as tricks and betrayals. Thus much public participation in environmental policy making never gets beyond a debate about who is telling the truth about risk and what the risks really are. Paradoxically, while this debate is often highly emotional on both sides, debates about calculating risks are profoundly scientific and should be at least partially resolvable within a scientific framework.
For example, in the debate over the toxicity of chlor-organics, Greenpeace is attempting to represent the public interest. In the process of evaluating the potential toxicity of new compounds Greenpeace demands that scientific proof be certain. The same reasoning is used by citizens who live near a proposed site for an incinerator, chemical weapons disposal installation, or landfill. They demand clear and highly certain scientific evidence of safety before accepting any new risk.
On the other hand, when there is public discussion about the connection between existing sources of potential pollution and local health problems, the public does not accept the burden of absolute proof. Those who live in a chemically polluted area do not want to wait until the causal connection between their children's ill heath and a leaking hazardous waste landfill is clearly and clinically established. They see a probable connection as a sufficient cause for action. In such situations the public is intolerant of risk, and is willing to act upon scientific uncertainty.
The diagram below summarizes the pattern of different people's response to risk: the general public as opposed to the majority of scientists and policy makers.
Type of Risk Assessment Preferred Criteria of For Evaluating Proof Existing Hazards Proposed New Plants or Substances Probabilistic Public Industry Deterministic Industry Public
Despite existing opportunities for delay, the current United States Congress is proposing new legislation, the "Risk Assessment and Cost Benefit Act of 1995" which could be used to delay environmental laws and standards even further. This bill requires every single law or regulation having a potential economic impact of more than 25 million dollars to undergo a thorough risk analysis and a cost benefit analysis. (Cost-benefit analysis requires putting a specific dollar value on every possible expense associated with the implementation of a regulation, including human health costs, also putting a dollar value on every benefit, including recreational and scenic value, and then comparing the two.)
Most significantly, the proposed law also provides new and abundant opportunities for challenges in court. Critics of the law suspect that the new U.S. Congress, which has announced its intention to suspend all governmental rule making for a year, is using risk assessment and its potential for endless scientific debates to completely derail all environmental protection activities. In the United States in the near future, risk assessment could become a weapon and not a tool of environmental policy making.
An alternative which expedites risk assessment is a California law which, very significantly, was introduced by a citizen-initiated referendum in 1986. The Safe Drinking Water and Toxic Enforcement Act, "Proposition 65," provided industry with an economic incentive to cooperate in the process of concluding risk assessment studies and in setting quantified environmental standards. The California law required that all suspected toxic substances for which no risk criteria had been established would be classified as potentially carcinogenic after a certain date. All products containing these substances would have to be be clearly labeled as toxic and would be forced to compete in the marketplace with products not labeled as toxic. In order to avoid negative advertising and possible legal liability, California industries cooperated with the state government in creating standards for regulating toxic substances. Risk assessments were conducted on two hundred and eighty two chemical substances in just a few years. There have not been any court challenges of the risk assessments or of the resulting regulations. The California Environmental Protection Agency described the impact of the incentive program as "One hundred years of progress [by federal standards] in the areas of hazard assessment and exposure assessment." California standards are generally more strict, and provide more protection for the consumer, than do federal standards.
By comparison, the United States national program, which allows and may now encourage delays, has set only a small fraction of such standards in several decades of work. Risk assessment can work, if it is coupled with the needed decision making incentives.