Wastewater-based assessment of regional and temporal consumption patterns of illicit drugs and therapeutic opioids in Croatia.

A comprehensive study of spatial and temporal consumption patterns of the selected illicit drugs (heroin, cocaine, amphetamine, MDMA, methamphetamine, cannabis) and therapeutic opioids (codeine, methadone) has been performed in six Croatian cities by applying wastewater-based epidemiology. The investigated cities (Bjelovar, Vinkovci, Varazdin, Karlovac, Zadar and Zagreb) varied widely in the population size (27,000-688,000 inhabitants) as well as in the number of registered drug consumers included in compulsory and voluntary medical treatment and rehabilitation programs (30-513 persons/100,000 inhabitants of age 15-64). The most consumed illicit drugs were cannabis (10-70doses/day/1000 inhabitants), heroin (<0.

Multiresidual analysis of emerging amphetamine-like psychoactive substances in wastewater and river water.

Besides the common illicit drugs, such as cocaine, heroin, and marijuana, there is a growing concern about the use of modern "designer drugs" that have emerged in large numbers over the past few years. In this work, a sensitive and selective method for simultaneous determination of 25 synthetic amphetamine-like psychoactive compounds, including amphetamine, sympathomimetic substituted amphetamines, synthetic cathinones and ketamine, in raw wastewater (RW), secondary effluent (SE) and river water was developed. Samples were enriched by solid-phase extraction (SPE) on mixed-mode reversed-phase/strong cation-exchange sorbent (Oasis MCX) and analysed by reversed-phase liquid chromatography coupled to electrospray ionisation tandem mass spectrometry (LC-MS/MS).

Assessment of stability of drug biomarkers in municipal wastewater as a factor influencing the estimation of drug consumption using sewage epidemiology.

Stability of the selected urinary biomarkers of six illicit drugs and two therapeutic opioids in municipal wastewater was studied in order to determine errors associated with their possible transformation in the sewer. The stability was assessed in experiments conducted at 10°C and 20°C in order to simulate typical winter and summer temperature conditions in the sewer system. Among fourteen substances tested, the most unstable compounds were morphine-3-β-D glucuronide (MG), 6-acetyl morphine (6-AM), cocaine (COC) and 6-acetyl codeine (6-AC), while all other investigated compounds appeared to be relatively stable over a period of 72 h.

Integrated procedure for multiresidue analysis of dissolved and particulate drugs in municipal wastewater by liquid chromatography-tandem mass spectrometry.

For the first time, an integrated procedure for a quantitative multiresidue analysis of dissolved and particulate illicit drug target residues was developed and validated in three different wastewater matrices. The procedure consists of a comprehensive sample enrichment, fractionation and cleanup followed by the determination of target analytes by triple quadrupole liquid chromatography-tandem mass spectrometry in both positive and negative ionisation polarities. The enrichment of illicit drugs from suspended solids and aqueous samples was performed using pressurised liquid extraction and solid phase extraction (SPE), respectively.

ICP-AES determination of minor- and major elements in apples after microwave assisted digestion.

The aim of this paper was to determine the content of minor and major elements in apples by inductively coupled plasma atomic emission spectrometry (ICP-AES). Prior to ICP-AES measurement, dried apples were digested in a microwave assisted digestion system. The differences in the measured element concentrations after application of open and closed microwave system as sample preparation procedures are discussed.