The use of economic instruments, tradeable pollution rights and environmental standards all assume that the environment has a certain capacity to absorb waste materials without long-term damage: in other words, they assume that the environment has an assimilative capacity. This idea is based on the fact that some wastes, such as organic wastes that occur naturally, will decompose and break down in the environment if there are not too many of them in the one place at the one time. Other materials, such as some metals, may exist naturally in the environment at very low concentrations.

The Business Council of Australia (1991) favours an approach that takes account of the assimilative capacity of the local environment. It interprets sustainable development to mean that wastes should not be allowed to exceed the capacity of the environment to absorb them. However, it argues that this capacity is not a scientific fact but 'will depend heavily on the level of community wealth and living standards', because people place more value on clean air and water as they become more wealthy.

The council is critical of the tendency for Australian regulatory authorities to import standards from overseas and use them here. It argues that, since Australian pollution problems are not as severe as those overseas, standards need not be as strict. If this were the case, it says, Australia could do the world a favour by carrying out polluting processing activities here 'to relieve the burden on countries already at environmental capacity' (1991, pp. 7&endash;8).

In contrast, many environmentalists do not accept the idea of regulating waste streams to take advantage of the environment's assimilative capacity. For example, Greenpeace argues that this approach is highly dependent on the ability of scientists to assess the impact of pollutants on the environment and to determine a safe level that will not irreversibly or severely damage the environment. They argue that scientists are unable to do this, given the huge diversity of chemicals in use and the limited nature of testing they are subject to. Therefore, one cannot safely say that the environment can absorb a certain level of wastes. (1990a)

Greenpeace argues that acceptance of the precautionary principle would mean doing away with 'the permissive principle based on the assimilative capacity approach'. It argues that, when scientific uncertainty and debate exists, the environment should be given the benefit of the doubt. It quotes a document issued from the Nordic Council's Conference on Pollution of the Seas in 1989, which defined the precautionary principle as:

"eliminating and preventing pollution emissions where there is reason to believe that damage or harmful effects are likely to be caused, even where there is inadequate or inconclusive scientific evidence to prove a causal link between emissions and effects." (1990b, p. 4)

Greenpeace argues that the assimilative capacity approach assumes that scientists have enough knowledge to assess the impact of chemicals using rudimentary tests for toxicity, persistence and bioaccumulation, and that they can use this assessment to say that the environment can take a certain level of those chemicals. The organisation claims that with three hundred thousand chemicals being invented each year, and seventy thousand in daily use, scientists cannot possibly keep up; and that, although pollutants are tested for toxicity, persistence and bioaccumulation, they can have other damaging impacts, including altering salinity, physical smothering and thermal pollution. It argues that, given the large uncertainties, the assimilative capacity approach is not scientifically valid, and that a precautionary approach would demand that pollutants be progressively removed from the environment altogether through clean production techniques (1990b, p. 4). These techniques will be discussed further in part 5.)

Similarly, Robert Fowler, the director of the environmental law and policy unit at the University of Adelaide, argues that traditional approaches to regulation which set 'allowable' discharges or emissions have failed to reduce global pollution and are rapidly losing credibility. He points out that plants and animals and ecosystems interact with chemicals in such complex ways that assumptions about assimilative capacity and 'safe levels' of pollution or exposure bear little relation to reality. He agrees with the Greenpeace approach that precautionary action requires a shift from pollution control to pollution prevention (Australian Environment Review 1991).

Back...