Evaluation of commercially available methamphetamine presumptive tests for site contamination

Abstract

Presumptive tests or lateral flow immunoassay testing kits are increasingly being utilised as a fast, portable, cost-effective method to detect an array of analytes, particularly illicit drugs. In Australia, the methamphetamine and decontamination industry regularly use presumptive testing kits to determine whether a property is contaminated. These presumptive test kits advertise a detection limit of 0.5 µg/100 cm2 and above for methamphetamine. The performance of seven methamphetamine presumptive test brands and their kit components were analysed in this study. Following the kit instructions, each kit was analysed using a ceramic tile that was spiked with a known concentration of methamphetamine. These presumptive test kits were highly sensitive, with positive results also found below the limit of detection. Therefore, if there is a negative result it is likely that there is no methamphetamine present. Those that return a positive result require further quantitative assessment. Thus, the presumptive test kits may detect the presence of methamphetamine that is below the Australian Clandestine Drug Laboratory Remediation Guideline of 0.5 µg/100 cm2. This indicates these tests might be useful as a screening assessment but should not be relied upon to develop a remediation action plan.