Science - Science and Regulation

Industry arguments	Intervenor arguments eg environmentalists
chemical occurs naturally no evidence chemical causes harm at level of proposed standard standard should be based on practicable technology	chemical is dangerous substance no proof chemical is safe at level of proposed standard standard should be based on environmental protection

uncertainty can be used both ways

where does onus of proof lie?

In a study of the politics of regulation in Europe and the USA, Ronald Brickman and his colleagues concluded that scientific uncertainties 'make it possible for proponents and opponents of regulation to interpret the scientific basis for cancer risk assessment in ways that advance their particular policy objectives' (1985, p. 187). There is no scientific way to know whether a substance will cause cancer in humans without testing it on humans&emdash;which would be unethical. Scientists disagree over how chemicals should be tested and how the results of those tests should be interpreted. Tests used include short-term tests for mutagenic (cell-mutating) activity; high doses on animals such as mice; and studies of humans who have been accidentally exposed to the substances.

Brickman and his colleagues found that the consequences that should follow from a positive test were disputed:

"Some environmentalists resolutely maintained that positive evidence from one or more short-term tests should trigger regulation, even without convincing support from other sources. At the other extreme, some witnesses for industry argued that no significance should be attached to these tests until they are more thoroughly validated." (p. 197)

Using animal tests to determine whether a substance is carcinogenic (cancer causing) in humans is equally controversial, with disagreements over such things as how experiments should be designed and whether tumours induced at high doses in animals are relevant to exposure of humans to low doses of the same chemical. A US study reported by Frances Lynn (1986) found that far more people from industry (73 per cent) disagreed with the use of animal tests than people from government (31 per cent) or university (48 per cent); and that 'those who question the use of animal data to predict carcinogenesis in humans are more likely to hold conservative political attitudes' (p. 46).

The regulator is forced to make a decision even though there is scientific uncertainty and debate. He or she is often faced with the situation that a product which has high social or economic benefits has shown some indications of being carcinogenic. On the other hand, the costs of not limiting a chemical might be even greater in terms of human health and environmental damage than the benefits of leaving it freely on the market. A regulator generally does not have the luxury of waiting around until more compelling evidence comes in. Not acting on the given information is just as much a decision as acting.

Regulators react to this dilemma differently in different countries. In the USA, the EPA is far more ready to regulate on the basis of experiments done in the laboratory than are the equivalent authorities in France and Germany. For example, German regulators do not automatically view substances that cause cancer in animals as being a threat to humans. British regulators also require much more 'proof' than do US regulators. An example is the case of aldrin and dieldrin which were banned in the USA but not in Britain or Australia, although the same data was available to regulators in each country (Gillespie et al. 1982, pp. 303&endash;35).

The US regulators also take a more precautionary approach when it comes to the question of threshold effects: they are far more willing to prohibit chemicals for particular uses than in Australia, despite the financial cost that might be involved. Australian regulators follow their British counterparts, being more willing to accept the idea of threshold levels. Brickman et al. (1985) quote a US interagency agreement that states that because threshold doses that cause cancer have not been established 'a prudent approach from a safety standpoint is to assume that any dose may induce or promote carcinogenesis' (p. 208). This stance was condemned by industry, the courts and sections of the public as being 'unduly restrictive and insensitive to socioeconomic costs' (p. 210). In contrast, the British insistence that scientific evidence supports the existence of thresholds has been met with fierce union opposition in the area of occupational health and safety.

Even in the USA, laboratory evidence that a chemical causes cancer is not always enough to result in the banning of chemicals. For example, 2,4,5-T (the active chemical in some herbicides) received only a partial ban after there was evidence that human foetuses had been adversely affected by it, despite earlier laboratory results that indicated it was a problem.

Should a chemical be assumed safe until proven dangerous, or should the chemical not be used until it has been proven to be relatively harmless? Normally, people are innocent until proven guilty. But should the same rule apply to chemicals? Like many environmentalists and regulators, Steven Jellinek of the US EPA argues that granting civil rights to toxic substances does not make sense, and that the burden of proof should be on those wanting to use or dispose of the chemicals to prove they are safe before releasing them. 'Rarely will there be overwhelming evidence of a hazard&emdash;the smoking gun or dead bodies&emdash;but the most obvious implication of this sort of proof is that we have waited too long to take precautionary action' (Jellinek 1980, pp. 8&endash;9).

Of course, uncertainty is associated not only with chemical pollutants but also with nearly every environmental problem, including the global problems of ozone depletion and global warming. Policy-makers and their scientific advisers cannot know what the exact impact of additional ultraviolet radiation will be. Increasing controversy surrounds the tentative predictions by atmospheric scientists that global warming will result from human-generated greenhouse gas emissions. Such uncertainties provided an excuse for politicians such as former US president George Bush to delay actions to reduce greenhouse gas emissions while he waited for more scientific evidence.

Source: Sharon Beder, The Nature of sustainable Development, 2nd ed., Scribe, Newham, Victoria, 1996, pp. 122-124.