ABSTRACT
In order to develop effective policies, decision-makers rely upon the best available scientific data. However, scientific uncertainty regarding, inter alia, epidemiological evidence of causal linkages between activities and impacts, thresholds at which damage becomes significant or irreversible, long-term cumulative or combined effects of pollutants has, by hindering agreement, historically impeded international lawmak ing for the protection of the environment. Also, the ever increasing sophistication of scientific methodologies may, in some instances, lead to uncertainty over the nature of any scientific methodology used and data collected. 1 In order to avoid this ‘paralysis of uncertainty’, international instruments for environmental protection created since the 1 9 8 0 s have often permitted or compelled State parties to proceed on the basis of a ‘precautionary’ approach. This approach was pioneered in German national environmental law during the 1 9 7 0 s and 1 9 80 s as the principle of precautionary action or ‘Vorsorgeprinzip ’ 2 and it is hardly surprising therefore that its first explicit inclusion in an international declaration was due to the insistence of the Federal Republic of Germany.3
