The principles of Good Laboratory Practice (GLP) promote the quality and validity of data generated in the testing of chemicals and prevent fraudulent practices.


The principles have been developed in accordance with the Organization for Economic Cooperation and Development (OECD) and the EU has adopted these principles and the revised OECD Guides for Compliance Monitoring Procedures for GLP as annexes to its two GLP Directives.


GLP underpins the mutual acceptance of test data between countries, which avoids duplicative testing, is beneficial to animal welfare, and reduces costs for industry and governments.


Common principles for GLP also facilitate the exchange of information and prevents the emergence of non-tariff barriers to trade, while contributing to the protection of human health and the environment.


The principles of GLP define a set of rules and criteria for a quality system concerned with the organizational process and the conditions under which non-clinical health and environmental safety studies are planned, performed, monitored, recorded, reported and archived.


International aspects

The EU has concluded Mutual Recognition Agreements for GLP with Israel, Japan, and Switzerland. The European Regulations and Directives also apply to Iceland, Liechtenstein, and Norway.


Following Decision C (97)186/Final of the OECD Council, data generated in the testing of chemicals in an OECD Member Country, in accordance with OECD Test Guidelines and the principles of GLP, are accepted in other OECD Member Countries (e.g. Australia, Canada, Korea, and the USA). 


This also applies to certain non-OECD member countries that are full adherents to the mutual acceptance of data (MAD) in accordance with OECD Council Decision C(97)114/Final (Brazil, India, Malaysia, Singapore and South Africa, as well as Argentina for industrial chemicals, pesticides and biocides only.)


EU legislation/regulations on GLP:

- Directive 2004/9/EC lays down the obligation of EU countries to designate the authorities responsible for GLP inspections in their territory. It also comprises reporting and internal market (mutual acceptance of data) requirements. The Directive requires that the OECD Revised Guides for Compliance Monitoring Procedures for GLP, as well as the OECD Guidance for the Conduct of Test Facility Inspections and Study Audits, be followed during laboratory inspections and study audits. Directive 2004/9/EC has replaced Directive 88/320/EEC as of 11 March 2004.


- Directive 2004/10/EC requires EU countries to take all measures necessary to ensure that laboratories carrying out safety studies on chemical products comply with the OECD Principles of Good Laboratory Practice. Directive 2004/10/EC replaces Directive 87/18/EEC.


Resource Person: Barbara Pirola