Degradation pattern of illicit drugs in soil

The abuse of illicit drugs has received worldwide attention due to their significant adverse impacts on human and the environment. The aim of the present work was to determine the degradation pattern of certain compounds (associated with the clandestine manufacture of illicit drugs) in soil. The target compounds include parent drug (methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA)), precursors (pseudoephedrine), and by-products (1-(1,4-cyclohexadienyl)-2-methylaminopropane, Nformylmethylamphetamine, and 1-benzyl-3-methylnaphthalene). The environmental fate of the target compounds were evaluated in three different South Australian soils under non-sterile and sterile conditions. The results of the degradation study indicated that 1-benzyl-3-methylnaphthalene, methamphetamine, and Nformylmethylamphetamine persist for a long time in soil, MDMA and pseudoephedrine persist for a moderate time, and 1-(1,4-cyclohexadienyl)-2-methylaminopropane is not persistent. The role of bioticabiotic soil processes on the degradation of target compounds was also varied significantly for different soils as well as with the progress in incubation period. The degradation of methamphetamine and 1-benzyl-3methylnaphthalene can be considered as predominantly biotic as no measureable changes in concentrations were recorded in the sterile soils within one year period. The results of the present study revealed that the degradation pattern depends mostly on the soil conditions and the nature of the compound.