Good Laboratory Practice

The principles of Good Laboratory Practice (GLP) ensure the quality and validity of data generated by testing chemicals.

The principles were elaborated by the Organisation for Economic Cooperation and Development (OECD) and incorporated into EU law through the GLP directives, together with the revised OECD Guides for Compliance Monitoring Procedures for GLP.

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

• Directive 2004/9/EC obliges EU countries to designate the authorities responsible for GLP inspections in their territory. It also includes 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 2004/10/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. 

The principles of GLP are applied to the non-clinical safety testing of test items contained in a range of products. The application of GLP principles is required by a variety of different sectoral legislation (310 kB).

International aspects

The EU has concluded Mutual Recognition Agreements on GLP with Israel, Japan, and Switzerland. The GLP 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 the OECD's test guidelines and the principles of GLP, is accepted in other OECD member countries. 

This also applies to certain non-OECD member countries that are full adherents to the Mutual Acceptance of Data (MAD) system, in accordance with OECD Council Decision C(97)114/Final. 

See the list of National GLP Compliance Monitoring Programmes which participate in the MAD system for further information.

Useful links

• The OECD's Good Laboratory Practice webpage

  Guidance

  • Questions & Answers (567 kB)
  • Guidance on GLP compliance monitoring of international multi-site studies

  Practical implementation

  • Inspected test facilities (366 kB)
  • Guidance for GLP facilities on implementing and maintaining a risk-based quality assurance programme
  • Guidance on cross-contamination of control samples with test items in animal studies
  • Brexit: see this sectoral guidance notice for stakeholders

  Contact points

  • GROW-GLPec [dot] europa [dot] eu (European Commission)
  • National authorities