Pholedrine is a marker of direct disposal of methamphetamine

Amphetamine-type drug-related fatalities in the context of 8 years of methamphetamine use measured by wastewater analysis in South Australia

Methamphetamine is the illicit stimulant of choice in Australia. Countless initiatives have been employed to reduce methamphetamine use and drug-related harm. Wastewater analysis (WWA) has been used effectively as an objective measure of drug use at a population level and can be compared to indicators of harm, such as the number of drug-related fatalities. This paper attempts to describe methamphetamine use in the context of changes in levels measured in wastewater in South Australia whilst recognising considerable interventions over an 8-year period. Validated liquid chromatography-mass spectrometry methods were used to determine methamphetamine (and MDMA) levels in wastewater over an 8-year interval. The number of drug-induced deaths and driver fatalities involving methamphetamine (and MDMA) was presented and described in the context of changes in use measured by WWA. A rise in methamphetamine use according to WWA was evident up to 2017, followed by a gradual decrease to 2020 back to 2015 levels. Both driver fatalities and drug-induced deaths correlated well with use measured by WWA over the 8-year period. Multiple initiatives to curb supply, distribution and harm within the state and nationally have been implemented. The decrease in methamphetamine use after 2017 suggests that timely interventions have successfully reduced overall drug use and has led to fewer fatalities. This study shows that the response to increasing methamphetamine use in South Australia has resulted in a reversal of the upward trend in consumption and fewer drug-related fatalities.

Biomarker selection strategies based on compound stability in wastewater-based epidemiology

The specific compositions of human excreta in sewage can be used as biomarkers to indicate the disease prevalence, health status, and lifestyle of the population living in the investigated catchment. It is important for guiding and evaluating public health policies as well as promoting human health development. Among several parameters of wastewater-based epidemiology (WBE), the decay of biomarkers during transportation in sewer and storage plays a crucial role in the back-calculation of population consumption. In this paper, we summarized the stability data of common biomarkers in storage at different temperatures and in-sewer transportation. Among them, cardiovascular drugs and antidiabetic drugs are very stable which can be used as biomarkers; most of the illicit drugs are stable except for cocaine, heroin, and tetrahydrocannabinol which could be substituted by their metabolites as biomarkers. There are some losses for part of antibiotics and antidepressants even in frozen storage. Rapid detection of contagious viruses is a new challenge for infectious disease control. With the deeper and broader study of biomarkers, it is expected that the reliable application of the WBE will be a useful addition to epidemiological studies.

Enantiomeric profiling of amphetamines in wastewater using chiral derivatisation with gas chromatographic-tandem mass spectrometric detection

Enantiomeric profiling can supplement wastewater-based epidemiology (WBE) by providing additional information on drug origin (licit or illicit), improving consumption estimates, i.e., differentiating between disposal and consumption, and offering an insight into the potency of drugs available on the illicit drug market. We report on the enantiomeric profiling of amphetamines in wastewater using R(-)-α-methoxy-α-(trifluoromethyl) phenylacetyl chloride (R-MTPCl), a chiral derivatising agent and GC-MS/MS. The method performed well when evaluated against the SANTE/12682/2019 guidelines in terms of recovery (81-99%), accuracy (99-111%), repeatability (1-8%RSD) and linearity (LOQ-1000 ng/mL). The LOD and LOQ were 120 ng/L and 400 ng/L, respectively. The method was applied to samples of raw wastewater from two Slovene municipalities with unusual levels of amphetamines: Ljubljana (LJ1) and Velenje (VE1). LJ1 had an anomalously high mass load of MDMA (3,4-methylenedioxymethamphetamine) identified during SCORE 2020, and VE1 is a representative sample of the consistently high mass load of amphetamine. A second Ljubljana sample (LJ2) was chosen as a representative sample. The presence of racemic MDMA (EF = 0.511) in LJ1 indicated the disposal of the unused drug into the sewer, while the enrichment of R-MDMA (EF = 0.666) in the combined extract sample from Ljubljana (LJ2) indicated consumption. In the case of Velenje and Ljubljana, it is impossible to distinguish between the direct disposal and consumption of amphetamine and methamphetamine. Also, since amphetamine/methamphetamine-based prescription medications are unavailable in Slovenia, racemic amphetamine in VE1 (EF = 0.514) and LJ2 (EF = 0.459) indicate racemic and the more potent S-amphetamine are sold on the illicit drug market. Only S-methamphetamine was detected in wastewater (LJ2: EF = 0), indicating the presence of only the more potent S-methamphetamine on the illicit drug market. Overall, enantiomeric profiling provided useful information on amphetamine residues. In addition, chiral derivatisation can be a cost-effective alternative to using chiral chromatographic columns for the enantiomeric profiling of amphetamines in wastewater.

Wastewater analysis of psychoactive drugs: Non-enantioselective vs enantioselective methods for estimation of consumption

The consumption of licit and illicit psychoactive drugs (PAD) is ubiquitous in all communities and a serious public health problem. Measuring drug consumption is difficult but essential for health-care professionals, risk assessment and policymakers. Different sources of information have been used for a comprehensive analysis of drug consumption. Among them, Wastewater based epidemiology (WBE) emerged as an essential and complementary methodology for estimating licit and illicit drugs consumption. This methodology can be used for quantification of unchanged drugs or their human-specific metabolites in wastewater for estimation of consumption or screening of new PAD. Although some limitations are still being pointed out (e.g., estimation of the population size, use of suitable biomarkers or pharmacokinetics studies), the non-invasive and potential for monitoring real-time data on geographical and temporal trends in drug use have been showing its capacity as a routine and complementary tool. Chromatographic methods, both non-enantioselective and enantioselective are the analytical tools used for quantification of PAD in wastewaters and further estimation of consumption. Therefore, this manuscript aims to summarize and critically discuss the works used for wastewater analysis of PAD based on WBE using non-enantioselective and enantioselective methods for estimation of consumption. Non-enantioselective methods are among the most reported including for chiral PAD. Nevertheless, a trend has been seen towards the development of enantioselective methods as most PAD are chiral and determination of the enantiomeric fraction can provide additional information (e.g., distinction between consumption or direct disposal, or manufacture processes) and fulfill some WBE gaps.