precautionary principle

The aim of the precautionary principle seems laudable: lacking scientific consensus, the burden of proof for an action or policy not being harmful to the public or to the environment lies on those taking that action. In practice, however, this principle has proven a deterrent for innovation - particularly within the EU. How can the innovation principle - that is, examining new policies or plans for a negative impact they have on innovation - help to supplement and balance out the precautionary principle?