The aim of the present study was to investigate the composition of heroin, amphetamine, and cocaine seized in the police district of Aarhus, the second largest city in Denmark, during a 2-year period. The purity of the active substance was measured together with the frequency and purity of adulterants and diluents present in the drugs. Results are compared with a similar study conducted ten years earlier. The concentrations of the active substances in illicit heroin, amphetamine, and cocaine samples have decreased significantly over a 10-year period. This finding shows that the "cutting" of illicit drugs is more prevalent and comprehensive today than it was 10 years ago. Also, the variety and quantity of adulterants and diluents have changed over time.
Open Forensic Science Journal, 2009, Vol 2, p. 16-20