OECD Guidelines for the Testing of Chemicals are a set of internationally accepted specifications for the testing of chemicals decided on by the Organisation for Economic Co-operation and Development (OECD). They were first published in 1981. They are split into five sections:
Section 1: Physical Chemical Properties
Section 2: Effects on Biotic Systems
Section 3: Degradation and Accumulation
Section 4: Health Effects
Section 5: Other Test Guidelines
Guidelines are numbered with three digit numbers, the section number being the first number. Sometimes guidelines are suffixed with a letter.
Guidelines are under constant review, with guidelines being periodically updated, new guidelines being adopted, and guidelines being withdrawn. Previous guidelines are maintained on the website for reference purposes. Animal welfare concerns are dealt with by ensuring that animal tests are only permitted where necessary.