Aderjan R., Herbold M., Skopp G.

Institute of Legal Medicine and Traffic Medicine, University of Heidelberg, Vosstr. 2, D-69115, Heidelberg, Germany

A new legal provision is being introduced in Germany. The German Road Traffic Act will be extended by which the presence of illicit drugs in blood of motorists will be regarded as a violation. Similar to a blood alcohol concentration above 0.80 per mille, analytical treshold values for blood drug concentrations are being defined.

The principal goals are to find out the number of labs capable to quantitatively determine traces of drugs of abuse and metabolites in serum and to compare the performance of forensic analytical toxicology labs at or above the critical treshold values.

In 1994 Institute of Legal Medicine and Traffic Medicine of the University of Heidelberg was ordered and supported by the German Ministery of Traffic via the Bundesandstalt für Straßenwesen to organiza proficiency testing for the most frequently abused drugs. The proficiency testings were organized in coordination with the Joint-Commission "Treshold Questions on Drugs or Abused Drugs" of the German Society of Legal Medicine and the German Society of Traffic Medicine.

Until March 1997, the following analytes were included in the test samples on serum:

Drug	Analyte	Concentration Range µg/L
Cannabis	Tetrahydrocannabinol, Tetrahydrocannabinol carboxylic acid	0 - 12
Heroin (morphine)	Morphine	10 - 125
Cocaine and metabolites	Benzoylecgonine, Cocaine	25 - 200
Amphetamines	Amphetamine, MDMA, MDEA	35 - 220

Since 1994 more than 100 laboratories from 10 nations participated in proficiency testing. In 1996 the schemes were enlarged for further classes of substances, alternative matrices and markers for alcohol misuse.

This presentation reports on strategic and design aspects to obtain objective and reliable data so that appropriate decisions can be made. From the experience obtained and the fruitful exchange this quality assurance strategy is intended to be established as a permanent institution.