"We need to continue and accelerate this process of risk assessment and risk management. However that, on its own, is not sufficient. Where we have strong concerns about particular chemicals, we should not wait for the results of full risk assessments before taking action - the precautionary principle makes it clear that we have an obligation to act to prevent serious harm to the environment or to human health even in the absence of full scientific certainty."

This principle says that where there is a risk of serious or irreversible damage, we should not wait until all the scientific proof is in.

However the question that this raises is: "When is the point we should implement the precautionary principle?". This question has been investigated for a wide range of substances in the following report

'Late lessons from early warnings:
the precautionary principle 1896 - 2000'.
European Environment Agency Report