As scientists and analysts, many of us find ourselves working in laboratories, busy doing analytical work or research, with little time or opportunity to step back from our busy daily routine to focus on the internationally recognised principles of Good Laboratory Practice (GLP). All too often we lose sight of the forest for the trees. GLP can sometimes be confused with the standards of laboratory safety, e.g. wearing appropriate gloves, safety goggles and clothing – which it is not. In some cases, GLP may have been implemented in a laboratory by management without all laboratory personnel being aware of what exactly GLP is.

So what is GLP?

GLP is a data quality management system which provides a framework (based on internationally accepted principles) within which laboratory studies are planned, performed, monitored, recorded, reported and archived. These laboratory studies can be undertaken to generate data so as to assess the benefits and risks to users, consumers and third parties, including the environment, of pharmaceuticals (only preclinical studies), agrochemicals, cosmetics, food additives, feed additives and contaminants, novel foods, biocides, etc.

GLP helps assure regulatory authorities that the data submitted are a true reflection of the results obtained during the study and can therefore be relied upon when making regulatory assessments. If a laboratory has been certified in GLP by a national certification body, results from that laboratory should be reliable, repeatable, auditable, and recognized by scientists internationally. Ideally, all scientists and analysts working in laboratories should have a good understanding of GLP so that there is no weak link in the chain of events in the laboratory leading to quality and valid test data.

Difference between Good Laboratory Practice and ISO 17025

You may wonder what the difference between GLP and ISO 17025 is. Some laboratories are accredited according to the International Standard Organization’s ISO 17025 which addresses and underwrites the technical competence of a laboratory to carry out specific tests on a continuing basis to defined standards. In general, it is agreed that the appropriate accreditation for commercial testing and calibration laboratories is to ISO 17025. However, many requirements of the GLP principles are not covered by, or are less stringent in ISO 17025 accreditation.

Benefits of Good Laboratory Practice

Laboratories in industrial private sector settings, in the public service sector, and in third level education institutions, not necessarily involved in commercial testing or calibration would benefit greatly from a comprehensive understanding of GLP principles and, ultimately, GLP certification. Laboratory personnel trained in GLP could carry with them their knowledge of GLP as a key skill which is recognised by the international scientific community.

GLP on a practical level stresses the importance of the following five points in the laboratory:

  • resources (which includes equipment validation and calibration),
  • characterization of test items (including sampling) and test systems,
  • rules (including SOPs, which provide in-depth instruction as to who does what, when, where and how),
  • results (including statistical analyses, calculation of measurement uncertainty, maintaining laboratory notebooks, writing scientific reports, intellectual property issues) and,
  • quality assurance (including audits).

If you would like to learn more about Good Laboratory Practice, feel free to book your place in our next upcoming public courses or call us on 087 9678 372 or email us

Author: Dr. Martina McGuinness