ABSTRACT
The results of measurements should provide reliable information and the laboratory should be able to prove the correctness of measurements with documented evidence. Analysts carry serious responsibilities to produce correct and timely analytical results, and are fully accountable for the quality of their work. The expanding national and international trade, the responsibility of national registration authorities permitting the use of various chemicals required long ago reliable test methods, which were acceptable by all parties concerned. The accuracy and precision of the analytical results may be assured by proficient analysts applying properly validated methods, which are fit for the purpose, in a laboratory accredited according to the relevant standards or guidelines.1,2 Several documents and guidelines had been, and are developed to assist the analysts to apply the relevant analytical quality control (AQC)3 quality assurance (QA) principles in their diverse daily work, and to provide guidance for accreditation purposes. The Codex Committee on Pesticide Residues (CCPR) continuously updates the Guidelines on Good Laboratory Practice,4
information on the minimum validation of methods. The EURACEM=CITAC* published additional guidelines on application of quality assurance in nonroutine laboratories,5 interpretation of proficiency test results,6 and traceability of measurements.7 These documents and GLs are complimentary to the requirements of the ISOy=IECz 17025 and OECD§ GLP Principles, and can be freely downloaded from the Internet.
