Sara Karolak

Comparing illicit drug use in 19 European cities through sewage analysis.

The analysis of sewage for urinary biomarkers of illicit drugs is a promising and complementary approach for estimating the use of these substances in the general population. For the first time, this approach was simultaneously applied in 19 European cities, making it possible to directly compare illicit drug loads in Europe over a 1-week period. An inter-laboratory comparison study was performed to evaluate the analytical performance of the participating laboratories. Raw 24-hour composite sewage samples were collected from 19 European cities during a single week in March 2011 and analyzed for the urinary biomarkers of cocaine, amphetamine, ecstasy, methamphetamine and cannabis using in-house optimized and validated analytical methods. The load of each substance used in each city was back-calculated from the measured concentrations. The data show distinct temporal and spatial patterns in drug use across Europe. Cocaine use was higher in Western and Central Europe and lower in Northern and Eastern Europe. The extrapolated total daily use of cocaine in Europe during the study period was equivalent to 356 kg/day. High per capita ecstasy loads were observed in Dutch cities, as well as in Antwerp and London. In general, cocaine and ecstasy loads were significantly elevated during the weekend compared to weekdays. Per-capita loads of methamphetamine were highest in Helsinki and Turku, Oslo and Budweis, while the per capita loads of cannabis were similar throughout Europe. This study shows that a standardized analysis for illicit drug urinary biomarkers in sewage can be applied to estimate and compare the use of these substances at local and international scales. This approach has the potential to deliver important information on drug markets (supply indicator).

Estimation of illicit drugs consumption by wastewater analysis in Paris area (France)

Illicit drugs consumption is actually an important public health concern that needs to be well defined to be managed. A new method, expressed as sewage epidemiology has been proposed by Daughton and developed by Zuccato. This method involves estimating the consumption from the measurement of drug residues in sewage. Several studies have been carried out, leading to an assessment of drugs consumption in some European countries. This work, carried out in Paris area (France) brings new data to this assessment and allows a comparison of cocaine and MDMA consumptions with European estimations. Four wastewater treatment plants (WWTPs) have been retained for the study, taking into account biological treatment, volume capacity, geographic location and social environment. Cocaine and its major metabolite benzoylecgonine (BZE), amphetamine, 3,4-methylenedioxymethamphetamine (MDMA) and buprenorphine were measured in raw water and WWTP effluent using HPLC-MS/MS after SPE extraction. Amphetamine was rarely detected. Cocaine and BZE were quantified at levels from 5 to 282 ng L(-1) and 15 to 849 ng L(-1), respectively. MDMA and buprenorphine concentrations remained under 20 ng L(-1). Cocaine consumption was estimated from cocaine or BZE concentrations measured in raw water and the results showed significant difference in drug taking during week or weekend. The estimated doses observed in this study are lower than those reported for others countries, especially Spain and Italy. MDMA consumption was estimated at lower levels than cocaine.

Modeling of hospital wastewater pollution by pharmaceuticals: first results of Mediflux study carried out in three French hospitals

A study has been carried out in three French hospitals in order to assess and model the pharmaceutical load in hospital wastewater and its impact in WWTP. This study, called Mediflux, consisted of three successive steps: first, an original prioritization procedure developed in our laboratory enabled us to select a list of relevant molecules from different Anatomical Therapeutic Chemical (ATC) classes containing pharmaceuticals for specific hospital use such as anesthetics or antineoplastic agents and pharmaceuticals dispensed in the community. Then, analytical quantification procedures were developed and validated according to 2002/657/EC European directive. Sampling campaigns were performed in three different hospitals, two located in the Paris area and one in a medium-sized city 150 km from Paris. Sampling was also carried out in wastewater treatment plants. At the same time, in order to model the pharmaceutical loads from hospitals, predicted concentrations were calculated as a first approach assuming it would be a single-box model, i.e. hospitals have no effect on drug loads and only human metabolism is taken into account to evaluate the fraction of drugs eliminated in hospital effluent. In the last step, the comparison of measured and calculated concentrations showed a satisfactory correlation for some pharmaceuticals, mainly those with short elimination half-lifes and weak human metabolism. For others, it appeared that modeling should take into account various factors such as out patient use, pharmacokinetic data and molecule stability in wastewater.

Applying sewage epidemiology approach to estimate illicit drug consumption in a tropical context: Bias related to sewage temperature and pH

Illicit drug consumption can be estimated from drug target residue (DTR) in wastewater, with the reliability of results being partly linked to DTR stability in the sewage network. However, wastewater temperature and pH drive the stability of molecules and, in this context, tropical conditions must be studied to specify the impact of residence time in the sewage network on DTR degradation. Warmth enhances biotic and abiotic processes such as degradation, leading to a decrease in oxygen content, and consequently, early diagenesis conditions in wastewater. In this study, we conduct laboratory studies under acidic pH and high temperature (30°C) conditions to determine the degradation half-lives of cocaine (COC), tetrahydrocannabinol, and heroine targets, allowing COC/benzoylecgonine (BZE) ratio variations to be predicted in sewage networks. A rapid COC degradation is observed, as already reported in the literature but without a short-term significant difference between 20°C and 30°C. Acidic pH seems to prevent degradation. Thus, theoretically, the use of COC as DTR is only reliable in acidic conditions, with the decrease in COC concentration being 6% at 8h, but over 40% in other conditions. By contrast, the use of BZE as DTR to estimate COC consumption, which is performed in practice, can be undertaken with the same back-calculation equation as used in temperate countries. However, 11-nor-delta-9-carboxytetrahydrocannabinol stability is more influenced by high temperature: concentration levels after 24h are 20% lower at 30°C than at 20°C, corresponding to a 20% and 40% decrease, respectively. Based on a mean residence time of 8h, underestimated cannabis consumption is close to 15% in tropical contexts, which is double that of temperate areas.

Theory versus practice, bacteriological efficiency versus personal habits: A bacteriological and user acceptability evaluation of filtering tools for people who inject drugs

INTRODUCTION AND AIMS People who inject drugs (PWID) are exposed to associated viral, bacterial and fungal risks. These risks can be reduced by filtration. Large disparities in the quality of filtration exist between the various available filters. This paper compares both performance and user acceptability of three filters for drug injection (cotton filters, Sterifilt® and wheel filters) by combining epidemiological and bacteriological analyses. DESIGN AND METHODS A cross-sectional epidemiological study (ANRS-Coquelicot) using time-location sampling combined with the generalised weight sampling method was conducted among 985 PWID in France. Two filtration-based bacteriological studies of 0.20- and 0.45-μm wheel filters, Sterifilt filters and cotton filters were also conducted. RESULTS The bacteriological study highlighted the value of using wheel filters with a porosity of less than 0.5 μm, as they limit the risk of bacterial and fungal infection. The results of this study clearly highlight a distinction between the efficiency of Sterifilt and wheel filters, the latter being more effective. Our epidemiological study highlighted that the use of cotton filters is widespread and routine, but is the subject of much criticism among PWID. Sterifilt is not widely used, and its adoption is slow. Finally, the wheel filter remains a largely untested tool. DISCUSSION AND CONCLUSIONS Low product retention and ease of use are the two most important factors for filters for PWID. Bacterial and fungal risk filtration is less important. It is essential to educate PWID about the benefits of wheel filters. [Jauffret-Roustide M, Chollet A, Santos A, Benoit T, Péchiné S, Duplessy C, Bara J-L, Lévi Y, Karolak S, Néfau T. Theory versus practice, bacteriological efficiency versus personal habits: A bacteriological and user acceptability evaluation of filtering tools for people who inject drugs. Drug Alcohol Rev 2018;37:106-115].

Exposure of an urban population to pesticides assessed by wastewater-based epidemiology in a Caribbean island

Wastewater-based epidemiology is an innovative approach to estimate the consumption of chemicals and their exposure patterns in a population, on the basis of measurements of biomarkers in wastewater. This method can provide objective real-time information on xenobiotics directly or indirectly ingested by a population. This approach was used to examine the exposure of the Martinique population to the three classes of pesticides: triazines, organophosphates and pyrethroids. Martinique island (French West Indies) is a closed market and has been closely monitored since the early 2000s when contamination with chlordecone, an organochlorine insecticide widely applied between 1972 and 1993 in banana plantations, became a critical political issue. The aim of this study was to identify and quantify the patterns of human exposure and compare the results to those from other countries. Wastewater was collected as 24-h composite samples and analysed for selected urinary pesticide metabolites by liquid chromatography-tandem mass spectrometry. Organophosphate and pyrethroid metabolites were found in all the samples up to 330 ng/L, while triazines were found only at trace levels. Mass loads indicated higher exposure to pyrethroids than in some cities in Europe, but lower exposure to triazines and organophosphates. The estimated human intake for pyrethroids was close to the Acceptable Daily Intake, but importation of these pesticides to Martinique was low. This study illustrates the high human exposure with indoor pesticide use in comparison to its use in agriculture.

Validation of an ultra-high-performance liquid chromatography-tandem mass spectrometry method to quantify illicit drug and pharmaceutical residues in wastewater using accuracy profile approach

The analysis of biomarkers in wastewater has become a common approach to assess community behavior. This method is an interesting way to estimate illicit drug consumption in a given population: by using a back calculation method, it is therefore possible to quantify the amount of a specific drug used in a community and to assess the consumption variation at different times and locations. Such a method needs reliable analytical data since the determination of a concentration in the ngL-1 range in a complex matrix is difficult and not easily reproducible. The best analytical method is liquid chromatography - mass spectrometry coupling after solid-phase extraction or on-line pre-concentration. Quality criteria are not specially defined for this kind of determination. In this context, it was decided to develop an UHPLC-MS/MS method to analyze 10 illicit drugs and pharmaceuticals in wastewater treatment plant influent or effluent using a pre-concentration on-line system. A validation process was then carried out using the accuracy profile concept as an innovative tool to estimate the probability of getting prospective results within specified acceptance limits. Influent and effluent samples were spiked with known amounts of the 10 compounds and analyzed three times a day for three days in order to estimate intra-day and inter-day variations. The matrix effect was estimated for each compound. The developed method can provide at least 80% of results within ±25% limits except for compounds that are degraded in influent.