See also the closely related subsection

WTO Law and Science in the same section.

The Precautionary principle as it is used today in public international law goes back to Principle 15 of the Rio Declaration which states:

"In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities.  Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent  environmental degradation."

It is situated at the core of the politically tense and legally uncertain relationship between the Biosafety Protocol and the WTO, especially its Agreement on Sanitary and Phytosanitary Measures (SPS). Whether we look at precaution as a principle, an approach or simply as a broad regulatory perspective that provides governments with tools to implement certain domestic sanitary or phytosanitary objectives, it has lead to deep divisions in many international negotiations on environmental and public health issues, which usually position the US and its allies against the European Union and often most developing countries. It should be emphasized that contrary to a common misconception, a scientific risk assessment is a fundamental component of a precautionary approach, especially under the Biosafety Protocol.