• precautionary principle

The precautionary principle is gaining more and more ground as a guideline in environmental policy. Quantitative risk assessment no longer seems sufficient. In point of fact, historical analysis of several debates showed me that different societal groups structurally use different “paradigms”, “world views”, or “frames” to evaluate threats of man-made substances.^1,2 Briefly, the two most contrasting views are*:

• Adherents of what I termed the risk assessment frame believe that knowledge is adequate, that emission control will work, and that nature is quite resilient. Hence, they fully accept a management model where emission-effect calculations are used to assess a possible danger, and in which emission reductions are an adequate response to avoid exceeding a danger threshold (see for example, CEFIC³).

• Adherents of the precautionary frame dispute that there is sufficient knowledge to be able to rely on this approach in the first place. Hence, they judge substances primarily on indicators reflecting factors like their inherent safety, the possibility that we are ignorant of possible effects, and the reversibility of contamination (which would allow wrong judgements to be corrected). Materials that can be produced safely without complex emission control, and for which waste management is easy, have their preference (see for example, Chemicals Policy Committee⁴, Stringer and colleagues⁵, and Thornton⁶).

Unfortunately, the debate between these groups often develops into a “dialogue of the deaf”. Parties on both sides simply caricature each other’s position: precaution would lead to a standstill of all innovation, it is claimed, and risk assessment neglects ignorance. This really is a pity as risk assessment and precaution are not mutually exclusive. …