Differences between Precautionary Principle and Risk Assessment

Risk assessment is based on setting an acceptable level of harm and giving low relevance to the lack of scientific evidence and certainty on which many decisions are based. Risk assessment perpetuates a ‘business as usual’ approach. The precautionary principle calls for dynamic change towards sustainability.

Taking Precautionary Action before Scientific Certainty of Cause and Effect

An underlying theme of the principle is that decision-making in the face of extreme uncertainly and ignorance is a matter of policy and political considerations. Science can inform that decision but it is foolish to think that “independent” or “sound” science can resolve difficult issues over cause and effect. In the end the decision to do nothing, carry on as before, or change course and take preventive action is a policy decision, not a scientific one.

Setting Goals

The precautionary principle encourages planning based on well-defined goals rather than on future scenarios and risk calculations that may be plagued by error and bias. For example, Sweden has set the goal of phasing out persistent and bioaccumulative substances in products by the year 2007. The government is now involving a variety of stakeholders in determining how to reach that goal. Sometimes called “backcasting” in contrast to the more usual “forecasting”of an uncertain future, this type of planning creates fewer miscalculations and spurs innovative solutions.

Seeking Out and Evaluating Alternatives

Rather than asking what level of contamination is safe or economically optimal, the precautionary approach asks how to reduce or eliminate the hazard and considers all possible means of achieving that goal — including foregoing the proposed activity. Needless to say, alternatives proposed to a potentially hazardous activity must be scrutinized as stringently as the activity itself.

Shifting Burdens of Proof

Proponents of an activity should prove that their activity will not cause undue harm to human health or ecosystems. Those who have the power, control, and resources to act and prevent harm should bear that responsibility. This responsibility has several components:

• Financial responsibility. Regulations alone are not likely to spur precautionary behavior on the part of governments or those who are proponents of a questionable activity. However, market incentives such as requiring a bond for the worst possible consequences of an activity or liability for damages, will encourage companies to think about how to prevent impacts. Such assurance bonds are already used in construction projects.
• The duty to monitor, understand, investigate, inform, and act. Under a precautionary decision-making scheme, those undertaking potentially harmful activities would be required to routinely monitor their impacts (with possible third-party verification), inform the public and authorities when a potential impact is found, and act upon that knowledge. Ignorance and uncertainty are no longer excuses for postponing actions to prevent harm.

The precautionary principle requires a new way of thinking about decision and weighing scientific and other evidence in the face of uncertainty. For this reason, a range of public representatives and the inclusion of viewpoints from many fields of expertise must be involved to look at all aspects of a proposed action. Structures to better involve the public in decision-making are required under a precautionary approach. For example the involvement of all people along a product chain is essential to move to a just and sustainable form of production.

Risk assessment is viewed by government agencies and those in industry as the “sound science” approach to decision-making, in which decisions are made on the basis of what can be quantified, without considering what is unknown or cannot be measured. Although few scientists will admit it, risk assessment and other “sound science” approaches to decision-making are highly reliant on policy and scientific assumptions — which are frequently unscientific or subjective.

Why did risk assessment become the standard for environmental policy?

Risk assessment was originally developed for mechanical problems such as bridge construction in which technical parameters are well defined and can be analyzed. During the 1970s, with the increased production of chemicals and new technologies, policymakers in the U.S. needed a decision-making tool to predict and manage harm. They focused on risk assessment and cost-benefit analysis to bridge the gap between uncertain science and the political need for decision-making. However, a great deal of faith was placed in the ability of science to model and predict harm in extremely complex ecological and human systems. Risk assessment was defended by government agencies and those in industry as the “sound science” approach to decision-making. However decision making is based on what can be quantified, without considering what is unknown or cannot be measured. Risk assessments, by nature, rely on many assumptions — which are frequently unscientific or subjective.

So, is there a role for risk assessment within a precautionary approach?

Yes. But only as a tool to help us better understand the hazards of an activity, and to compare options for prevention. It can also be used, in conjunction with democratic decision-making methods, to prioritize activities such as hazardous waste site cleanups.

There is a proper role for risk assessment in increasing our understanding, but as traditionally practiced, risk assessment has often stood in the way of protecting human health and the environment. The underlying basis of policy and decision-making must be precaution and prevention, rather than risk.