Genetically modified plants and the precautionary principle

The European regulation of genetically modified plants is a particular example of technological risk management that has become an essential part of the management of change. The role of regulators in this management process, when there are demands for regulatory action concerning unquantified (and sometimes unquantifiable) technological risks – with regulation under conditions of uncertainty – is explored. Where the retrospective evidence concerning a postulated risk scenario is sparse, the precautionary principle (PP) may be invoked. The origins of the European regulatory system, which applied until 17 October 2002 (Directive 90/220), why this has been revised (Directive 2001/18) and the probable impact of this revision are described. This is illustrated with risk assessments that have accompanied submissions for marketing approval for genetically modified plants under Directive 90/220. Some of the problems associated with the PP and the regulation of GM plants are discussed.