title: Survey on drugs-of-abuse testing in the European Union.
abstract: A survey on the quality of drugs-of-abuse testing in European laboratories was performed in 1993 (Part I) and 1994 (Part II). A total of 195 laboratories participated in Part I and 228 in Part II. There were 154 repeater laboratories. In each part of the survey, six urine samples were sent for analysis under routine conditions. A set of reference materials, including deuterated drug-standard solutions, was provided in Part II of the survey for optimization of analytical procedures. Screening for groups of substances was mainly performed by immunological techniques. Rates of false-positive (FP) results were 0 and 0.5%, respectively, in Parts I and II, and rates of false-negative (FN) results were 7.7% in Part I and 3.4% in Part II. Identification and quantitation of specific substances was mainly carried out by chromatographic methods, particularly gas chromatography coupled to mass spectrometry. Application of chromatographic methods showed a lack of sensitivity (14.9% and 16.7% FN in Parts I and II, respectively) and a lack of specificity (0.8% FP in Part I versus 1.1% in Part II). Repeater laboratories improved their results (17.4% FN in Part I versus 14.2% Part II). The improvement of repeater laboratories emphasizes the need of external quality control programs. The experience is being used as a basis for a recommendation on drug-testing guidelines by a group of European toxicologists.
authors.affiliation: Drug Abuse Research Unit, Autonomous University of Barcelona, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Badia
authors.forename: J
authors.initials: J
authors.lastname: Segura
authors.forename: A
authors.initials: A
authors.lastname: Artola
authors.forename: R
authors.initials: R
authors.lastname: de la Torre
mesh_terms: D019411:Clinical Laboratory Techniques / Q000592:standards*; D003625:Data Collection; D005062:European Union; D005189:False Positive Reactions; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D013287:Illicit Drugs; D007118:Immunoassay; D011786:Quality Control; D015813:Substance Abuse Detection / Q000592:standards*
chemical_list: D013287:Illicit Drugs