Accreditation of analytical laboratories and proficiency testing: experiences from Thailand on the issues of pesticide analysis.

Thailand, the economic growth of which largely depends on agriculture-based industry, recognizes the importance of international standards for harmonization of international food trade and for protection of human health from chemicals used as food additives or those present as contaminants. Pesticides which are widely used in Thailand are the anticholinesterase pesticides, pyrethroids, coumarin derivatives, bipyridinium salts, and to some extent organochlorine compounds such as DDT in malaria control. Proficiency testing and accreditation of laboratories are recognized as effective means to ensure quality and validity of data and to enable adequate risk assessment of pesticide residues in food, work environment and environment in general. The paper is a synthesis of relevant local reviews and in-depth interviews with experts in the area of pesticide laboratory accreditation and proficiency testing. The paper refers to other schemes for quality assurance such as ISO guide 25, ISO 9000, and ISO 14000, and addresses future prospects of ongoing activities such as accreditation of inspection bodies in the area of industrial chemicals and occupational safety and health.