Cocaine and metabolites in waste and surface water across Belgium

Hydrophilic interaction chromatography in drug analysis

Hydrophilic interaction chromatography (HILIC) is an increasingly popular alternative to conventional HPLC for drug analysis. It offers increased selectivity and sensitivity, and improved efficiency when quantifying drugs and related compounds in complex matrices such as biological and environmental samples, pharmaceutical formulations, food, and animal feed. In this review we summarize HILIC methods recently developed for drug analysis (2006–2011). In addition, a list of important applications is provided, including experimental conditions and a brief summary of results. The references provide a comprehensive overview of current HILIC applications in drug analysis.

Spatial distribution of illicit drugs in surface waters of the natural park of Pego-Oliva Marsh (Valencia, Spain)

BACKGROUND, AIM AND SCOPE

The Pego-Oliva Marsh is the second most important wetland in the Valencian Community (Spain). It is included in the RAMSAR agreement and represents one key point for migratory birds. Emerging contaminants from the human pressure, such as pharmaceuticals, illicit drugs and personal care product, are not included in the list of priority contaminants of the Water Framework Directive yet, and are neither monitored nor controlled. However, pollution of emerging contaminants can threaten the environment and even human health. In order to understand the status of the emerging contamination and recommend future rationalization of countermeasures, the occurrence of illicit drugs was investigated.

MATERIAL AND METHODS

Samples were collected at 23 sites from the main irrigation channels and the marsh. Illicit drugs were extracted using solid phase extraction and determined by liquid chromatography tandem mass spectrometry. The method detection limits ranged from 0.01 to 1.54 ng l(-1) and the recoveries from 57% to 120%.

RESULTS AND DISCUSSION

3,4-Methylenedioxymethamphetamine, ketamine, morphine, benzoylecgonine, cocaine, methadone, 6-acetylmorphine and nor-9-carboxy-tetrahydrocannabinol were detected. The mean concentrations were 0.62, 21.33, 1.30, 1.92, 2.25, 0.32, 0.04 and 0.07 ng l(-1), respectively. The highest concentrations were in the north of Pego-Oliva Marsh.

CONCLUSIONS

The pollution status by illicit drugs of the Pego-Oliva Marsh has been established. However, contamination levels in all the area of the natural park were low compared with those reported in other superficial waters.

Aptamers for pharmaceuticals and their application in environmental analytics

Aptamers are single-stranded DNA or RNA oligonucleotides, which are able to bind with high affinity and specificity to their target. This property is used for a multitude of applications, for instance as molecular recognition elements in biosensors and other assays. Biosensor application of aptamers offers the possibility for fast and easy detection of environmental relevant substances. Pharmaceutical residues, deriving from human or animal medical treatment, are found in surface, ground, and drinking water. At least the whole range of frequently administered drugs can be detected in noticeable concentrations. Biosensors and assays based on aptamers as specific recognition elements are very convenient for this application because aptamer development is possible for toxic targets. Commonly used biological receptors for biosensors like enzymes or antibodies are mostly unavailable for the detection of pharmaceuticals. This review describes the research activities of aptamer and sensor developments for pharmaceutical detection, with focus on environmental applications.

Possible social relevance of illicit psychotropic substances present in the atmosphere

Although the worldwide presence of illicit psychotropic compounds in the environment is well known, the social impact of drug abuse on the community has yet to be determined. Besides, the possibility of deriving indicators of the prevalence of drug abuse from the content of illicit substances in the air remains unexplored. In this study, the atmospheric concentrations of psychotropic compounds recorded in Italy were plotted vs. a series of criminal statistics. Meaningful links were found between atmospheric cocaine and the amount of drugs seized, the number of drug related crimes and the demand for clinical treatment recorded in the Italian regions. Atmospheric cocaine and cannabinoids also seemed to be correlated with tumour insurgence and mental disease frequency, respectively. However, further investigations are necessary to elucidate/explain/clarify if the behaviours observed for cocaine vs. the parameters usually adopted to estimate drug abuse prevalence (correspond to an effective relationships)/are directly linked, and to understand why the same approach failed when applied to cannabinoids. Moreover, according to our study illicit drugs are suspected to promote long-term ill health effects even when present at low concentrations the air.

Assessment of total uncertainty in cocaine and benzoylecgonine wastewater load measurements

To check the effectiveness of campaigns preventing drug abuse or indicating local effects of efforts against drug trafficking, it is beneficial to know consumed amounts of substances in a high spatial and temporal resolution. The analysis of drugs of abuse in wastewater (WW) has the potential to provide this information. In this study, the reliability of WW drug consumption estimates is assessed and a novel method presented to calculate the total uncertainty in observed WW cocaine (COC) and benzoylecgonine (BE) loads. Specifically, uncertainties resulting from discharge measurements, chemical analysis and the applied sampling scheme were addressed and three approaches presented. These consist of (i) a generic model-based procedure to investigate the influence of the sampling scheme on the uncertainty of observed or expected drug loads, (ii) a comparative analysis of two analytical methods (high performance liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry), including an extended cross-validation by influent profiling over several days, and (iii) monitoring COC and BE concentrations in WW of the largest Swiss sewage treatment plants. In addition, the COC and BE loads observed in the sewage treatment plant of the city of Berne were used to back-calculate the COC consumption. The estimated mean daily consumed amount was 107 ± 21 g of pure COC, corresponding to 321 g of street-grade COC.

Refining the estimation of illicit drug consumptions from wastewater analysis: co-analysis of prescription pharmaceuticals and uncertainty assessment

Wastewater analysis is a promising monitoring tool to estimate illicit drug consumption at the community level. The advantage of this technique over traditional surveys and other surveillance methods has been emphasized in recent studies. However, there are methodological challenges that can affect reliability. The objectives of this study were to systematically reduce and assess uncertainties associated with sampling (through a stringent optimization of the sampling method) and the back calculation of per capita drug consumption (through a refined estimation of the number of people actively contributing to the wastewater in a given period). We applied continuous flow-proportional sampling to ensure the collection of representative raw wastewater samples. Residues of illicit drugs, opioids, prescription pharmaceuticals and one artificial sweetener were analyzed by liquid chromatography coupled with tandem mass spectrometry. A parameter estimating the number of people actively contributing to wastewater over a given period was calculated from the measured loads of prescription pharmaceuticals, their annual consumption and relative excretion data. For the calculation of substance loads in sewage, uncertainties were propagated considering five individual components: sampling, chemical analysis, flow measurements, excretion rates and the number of people contributing to the wastewater. The daily consumption per 1000 inhabitants was estimated to be almost 1000 mg for cannabis and several hundred mg for cocaine, methamphetamine and ecstasy. With the best sampling practice and current chemical analysis, we calculated the remaining uncertainty to be in the range of 20-30% (relative standard deviation, RSD) for the estimation of consumed drug masses in the catchment; RSDs for the per capita consumption were lower (14-24%), as one of the biggest uncertainty components (i.e. error in flow measurements) cancels out in the proposed method for the estimation of the number of people contributing to the daily wastewater volume. In this study, we provide methodological improvements that substantially enhance the reliability of the estimation method--a prerequisite for the application of this technique to meaningfully assess changes in drug consumption and the success of drug intervention strategies in future studies.

Refined sewer epidemiology mass balances and their application to heroin, cocaine and ecstasy

The detection of illicit drugs in environmental matrices may be a cause for concern, both from the perspective of their potential environmental impacts and the fact that their presence in detectable concentrations would be an indicator of significant drug use. The primary goal behind recent studies on this subject has been to use measured influent concentrations of selected illicit drugs or their in vivo metabolites in the environment as a means of estimating the abuse level of these drugs and patterns of consumption. Thus-far, such calculations have hinged on the use of solitary excretion estimates from single studies of limited scope and/or studies of limited applicability. Therefore, the need exists to conduct a comprehensive meta-analysis of metabolic disposition studies to construct excretions profiles for the various illicit drugs and their in vivo metabolites. The constructed excretory profiles should not only provide mean excretion values but also indicate the expected variations in excreted fractions that arise due to differences not only in the metabolic capacity of users but also in the efficiencies of various routes of administration for a given illicit drug. Therefore, the primary goal of the research presented here was to refine sewer epidemiology extrapolation mass balances for various illicit drugs of interest by constructing their excretory profiles segregated by route-of-administration. After conducting such a study with a multi-national scope on illicit drugs including cocaine, heroin and ecstasy, the results obtained clearly indicate that extrapolation factors currently being used in literature for these drugs to enumerate prevalence of abuse required significant refinement to increase their reliability.

Evaluation of the presence of drugs of abuse in tap waters

A total of seventy samples of drinking water were tested for non-controlled and illicit drugs. Of these, 43 were from Spanish cities, 15 from seven other European countries, three from Japan and nine from seven different Latin American countries. The most frequently detected compounds were caffeine, nicotine, cotinine, cocaine and its metabolite benzoylecgonine, methadone and its metabolite EDDP. The mean concentrations of non-controlled drugs were: for caffeine 50 and 19 ng L(-1), in Spanish and worldwide drinking water respectively and for nicotine 13 and 19 ng L(-1). Illicit drugs were sparsely present and usually at ultratrace level (<1 ng L(-1)). For example, cocaine has mean values of 0.4 (Spain) and 0.3 ng L(-1) (worldwide), whereas for benzoylecgonine, these mean values were 0.4 and 1.8 ng L(-1), respectively. Higher concentrations of benzoylecgonine were found in Latin American samples (up to 15 ng L(-1)). No opiates were identified in any sample but the presence of methadone and EDDP was frequently detected. Total mean values for EDDP were 0.4 ng L(-1) (Spain) and 0.3 ng L(-1) (worldwide). Very few samples tested positive for amphetamines, in line with the reactivity of chlorine with these compounds. No cannabinoids, LSD, ketamine, fentanyl and PCP were detected.

Illicit drug consumption estimations derived from wastewater analysis: a critical review

The consumption of illicit drugs causes indisputable societal and economic damage. Therefore it is necessary to know their usage levels and trends for undertaking targeted actions to reduce their use. Recently, a new approach (namely sewage epidemiology) was developed for the estimation of illicit drug use based on measurements of urinary excreted illicit drugs and their metabolites in untreated wastewater. This review aims at critically evaluating the published literature and identifying research gaps of sewage epidemiology. Firstly, the existing analytical procedures for the determination of the four most used classes of illicit drugs worldwide (cannabis, cocaine, opiates and amphetamine-like stimulants) and their metabolites in wastewater are summarized and discussed. The focus lies on the sample preparation and on the analysis with chromatographic techniques coupled to mass spectrometry. Secondly, back-calculations used to transform measured concentrations in wastewater (in ng/L) into an amount of used illicit drug (in g/day per 1000 inhabitants or doses/day per 1000 inhabitants) are discussed in detail for the four groups of illicit drugs. Sewage epidemiology data from Spain, Belgium, UK, Italy, Switzerland and USA are summarized and compared with data from international organisations, such as the European Monitoring Centre for Drug and Drug Addiction (EMCDDA) and the United Nations Office on Drugs and Crime (UNODC). The results derived from wastewater analysis show in general good agreement with existing prevalence data (percentage of a population that uses illicit drugs at a given time) and demonstrate the potential of sewage epidemiology. However, this review confirms that future work should focus on further optimisation and standardisation of various important parameters (e.g. sample collection and back-calculations). In the future, sewage epidemiology could be used in routine drug monitoring campaigns as a valuable tool in addition to the classical socio-epidemiological studies for the determination of local, national and international illicit drug use.

Behavior of pharmaceuticals and drugs of abuse in a drinking water treatment plant (DWTP) using combined conventional and ultrafiltration and reverse osmosis (UF/RO) treatments

The behavior along the potabilization process of 29 pharmaceuticals and 12 drugs of abuse identified from a total of 81 compounds at the intake of a drinking water treatment plant (DWTP) has been studied. The DWTP has a common treatment consisting of dioxychlorination, coagulation/flocculation and sand filtration and then water is splitted in two parallel treatment lines: conventional (ozonation and carbon filtration) and advanced (ultrafiltration and reverse osmosis) to be further blended, chlorinated and distributed. Full removals were reached for most of the compounds. Iopromide (up to 17.2 ng/L), nicotine (13.7 ng/L), benzoylecgonine (1.9 ng/L), cotinine (3.6 ng/L), acetaminophen (15.6 ng/L), erythromycin (2.0 ng/L) and caffeine (6.0 ng/L) with elimination efficiencies ≥ 94%, were the sole compounds found in the treated water. The advanced treatment process showed a slightly better efficiency than the conventional treatment to eliminate pharmaceuticals and drugs of abuse.

Sewage epidemiology--a real-time approach to estimate the consumption of illicit drugs in Brussels, Belgium

The sewage epidemiology approach was applied to a one-year sampling campaign in the largest wastewater treatment plant (WWTP) in Belgium. The consumption of cocaine (COC), amphetamine (AMP), methylenedioxymethamphetamine (MDMA), methamphetamine (METH), methadone (MTD) and heroin (HER) was evaluated based on measured concentrations of the parent compound and/or metabolites in daily 24-hour composite influent wastewater samples. The inevitable back-calculations used in the sewage epidemiology approach were adapted to newly available information regarding the stability of the compounds in wastewater and the excretion pattern of illicit drugs. For COC, three different back-calculation approaches were evaluated. In addition, for the first time, efforts were made to calculate the number of inhabitants living in the catchment area of the WWTP in a real-time and dynamic way, based on concentrations of nitrogen, phosphorus and oxygen in the wastewater samples. Clear variations in the amount of inhabitants in the catchment area of the WWTP were observed. For COC, AMP and MDMA a significant higher weekend use was observed while for HER and MTD no significant daily variations could be found. METH consumption was negligible. Generally, the sewage epidemiology calculations were in agreement with official statistics. This manuscript shows that sewage epidemiology provides consistent and logical results and that it is a promising tool that can be used in addition to classical studies to estimate illicit drug use in populations. Therefore, efforts should be made to further optimize this approach in the future.

Evaluation of drugs of abuse use and trends in a prison through wastewater analysis

Illicit drugs and metabolites have been recognized recently as a group of emerging contaminants of concern, as a consequence of their high volumes of use and production. Drug residue levels in the aquatic environment have also been pointed out as good indicators of illicit drug abuse. The present work assesses for the first time drug abuse in a penal complex from the levels of different drug residues measured in the prison sewage waters and evaluates the suitability of this approach to track and control illicit drug usage in such facilities. The presence of various drugs of abuse and metabolites in sewage waters from a penal complex was determined by an analytical method based on on-line solid phase extraction-liquid chromatography-tandem mass spectrometry. Levels of consumption indicators measured in this water were used to back-calculate drugs usage in the penal complex. Daily use was observed for methadone (average of 156 doses/day/1000 inh), alprazolam (129 doses/day/1000 inh), ephedrine (46 doses/day/1000 inh), cannabis (33 doses/day/1000 inh.) and cocaine (3 doses/day/1000 inh). Sporadic consumption was observed for heroin, amphetamine, methamphetamine, and ecstasy. In spite of the fact that this and other sewage epidemiological approaches described may suffer from bias that still need to be investigated and refined, it provides near "real-time" information on collective drug use in an anonymous way and constitutes a very useful, economic and fast tool to evaluate the efficiency of measures adopted to control and track drug abuse in this type of facilities (or any other provided that has a STP associated or an accessible collector system).

Illicit drugs: contaminants in the environment and utility in forensic epidemiology

The published literature that addresses the many facets of pharmaceutical ingredients as environmental contaminants has grown exponentially since the 1990s. Although there are several thousand active ingredients used in medical pharmaceuticals worldwide, illicit drug ingredients (IDIs) have generally been excluded from consideration. Medicinal and illicit drugs have been treated separately in environmental research even though they pose many of the same concerns regarding the potential for both human and ecological exposure. The overview presented here covers the state of knowledge up until mid-2010 regarding the origin, occurrence, fate, and potential for biological effects of IDIs in the environment. Similarities exist with medical pharmaceuticals, particularly with regard to the basic processes by which these ingredients enter the environment--excretion of unmetabolized residues (including via sweat), bathing, disposal, and manufacturing. The features of illicit drugs that distinguish them from medical pharmaceuticals are discussed. Demarcations between the two are not always clear, and a certain degree of overlap adds additional confusion as to what exactly defines an illicit drug; indeed, medical pharmaceuticals diverted from the legal market or used for non-medicinal purposes ar also captured in discussions of illicit drugs. Also needing consideration as par tof the universe of IDIs are the numerous adulterants and synthesis impurities often encountered in these very impure preparations. many of these extraneous chemicals have high biological activity themselves. In contract to medical pharmaceuticals, comparatively little is know about the fate and effects of IDIs in the environment. Environmental surveys for IDIs have revealed their presence in sewage wastewaters, raw sewage sludge and processed sludge (biosolids), and drinking water. Nearly nothing is known, however, regarding wildlife exposure to IDIs, especially aquatic exposure such as indicated by bioconcentration i tissues. In contrast to pharmaceuticals, chemical monitoring surveys have revealed the presence of certain IDIs in air and monetary currencies--the latter being of interest for the forensic tracking of money used in drug trafficking. Another unknown with regard to IDIs is the accuracy of current knowledge regarding the complete scope of chemical identities of the numerous types of IDIs in actual use (particularly some of the continually evolving designer drugs new to forensic chemistry) as well as the total quantities being trafficked, consumed, or disposed. The major aspect unique to the study of IDI's in the environment is making use of their presence in the environment as a tool to obtain better estimates of the collective usage of illicit drugs across entire communities. First proposed in 2001, but under investigation with field applications only since 2005, this new modeling approach for estimating drug usage by monitoring the concentrations of IDIs (or certain unique metabolites) in untreated sewage has potential as an additional source of data to augment or corroborate the information-collection ability of conventional written and oral surveys of drug-user populations. This still evolving monitoring tool has been called "sewer epidemiology" but is referred to in this chapter by a more descriptive proposed term "FEUDS" (Forensic Epidemiology Using Drugs in Sewage). The major limitation of FEUDS surrounds the variables involved at various steps performed in FEUDS calculations. These variables are summarized and span sampling and chemical analysis to the final numeric calculations, which particularly require a better understanding of IDI pharmacokinetics than currently exists. Although little examined in the literature, the potential for abuse of FEUDS as a tool in law enforcement is briefly discussed. Finally, the growing interest in FEUDS as a methodological approach for estimating collective public usage of illicit drugs points to the feasibility of mining other types of chemical information from sewage. On the horizon is the potential for "sewage information mining" (SIM) as a general approach for measuring a nearly limitless array of biochemical markers that could serve as collective indicators of the specific or general status of public health or disease at the community-wide level. SIM may create the opportunity to view communities from a new perspective--"communities as the patient." This could potentially lead to the paradigm of combining human and ecological communities as a single patient--as an interconnected whole.

Analysis of llicit and illicit drugs in waste, surface and lake water samples using large volume direct injection high performance liquid chromatography--electrospray tandem mass spectrometry (HPLC-MS/MS)

Llicit and illicit drugs represent a recent group of emerging contaminants and have been found in the aquatic environment. A HPLC-MS/MS method was developed using direct injection (DI) of larger volumes and a polar endcapped reversed-phase (RP) column to measure drug components in water samples belonging to the cocaine group, opiates, amphetamine-like stimulants and metabolites thereof. After validation, including sensitivity, linearity, recovery, precision and matrix effect studies, most drugs could be detected with limits of quantitation (LOQ) of 20 ng L(-1) in wastewater (WW) and 0.2 ng L(-1) in surface water. The major substances found in influents and effluents were cocaine (COC), benzoylecgonine (BE), morphine (MO), methadone (MD) and its main metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) with concentrations up to 2 μg L(-1), followed by codeine (COD) and the amphetamines which ranged between 20 and 400 ng L(-1). Except for MO, COD and EDDP levels were generally lower in the effluents. River and lake water contained trace amounts of mainly BE, MD and EDDP from the high pg L(-1) to the low ng L(-1) level. Monitoring COC and BE levels over 11 consecutive days in influents and effluents suggests a consumption preference on week-end days. Finally, measuring an influent after a major music event revealed that sewage treatment plants (STPs) are exposed, for a limited period of time, to high concentration peaks of COC and BE as well as amphetamine-like stimulants such as ecstasy (MDMA).

Current approaches to trace analysis of pharmaceuticals and personal care products in the environment

A large number of xenobiotics including pharmaceuticals and personal care products are continuously released into the environment. Effluents from sewage treatment plants are well known to be the major source for introduction of pharmaceuticals and personal care products into the aquatic system. In recent years, reliable methods have been established for residue analysis of these pollutants down to low ng/L levels. In this review, the different approaches to their trace determination are reviewed with special attention being paid to sample preparation procedures, state-of-the-art high-performance separation methods hyphenated with mass spectrometry, and immunochemical methods.

Quantification of drugs of abuse in municipal wastewater via SPE and direct injection liquid chromatography mass spectrometry

We present an isotopic-dilution direct injection reversed-phase liquid chromatography-tandem mass spectrometry method for the simultaneous determination of 23 drugs of abuse, drug metabolites, and human-use markers in municipal wastewater. The method places particular emphasis on cocaine; it includes 11 of its metabolites to facilitate assessment of routes of administration and to enhance the accuracy of estimates of cocaine consumption. Four opioids (6-acetylmorphine, morphine, hydrocodone, and oxycodone) are also included, along with five phenylamine drugs (amphetamine, methamphetamine, 3,4-methylenedioxy-methamphetamine, methylbenzodioxolyl-butanamine, and 3,4-methylenedioxy-N-ethylamphetamine) and two human-use markers (cotinine and creatinine). The method is sufficiently sensitive to directly quantify (without preconcentration) 18 analytes in wastewater at concentrations less than 50 ng/L. We also present a modified version of this method that incorporates solid-phase extraction to further enhance sensitivity. The method includes a confirmatory LC separation (selected by evaluating 13 unique chromatographic phases) that has been evaluated using National Institute of Standards and Technology Standard Reference Material 1511 Multi-Drugs of Abuse in Freeze-Dried Urine. Seven analytes (ecgonine methyl ester, ecgonine ethyl ester, anhydroecgonine methyl ester, m-hydroxybenzoylecgonine, p-hydroxybenzoyl-ecgonine, ecgonine, and anhydroecgonine) were detected for the first time in a wastewater sample.

Illicit drugs in wastewater of the city of Zagreb (Croatia)--estimation of drug abuse in a transition country

A comprehensive study of various psychoactive substances and their metabolites was performed in the wastewater treatment plant of the city of Zagreb (780 000 inhabitants) using liquid chromatography/tandem mass spectrometry (LC-MS-MS). The estimation of drug abuse for five different illicit drugs, including heroin, cocaine, marijuana, amphetamine and ecstasy, was made on the basis of their representative excretion rates, which were determined over a period of 8 months. Marijuana (1000 kg/year), heroin (75 kg/year) and cocaine (47 kg/year) were found to be the most frequently consumed illicit drugs, while the consumption of amphetamine-type drugs was much lower (1-3 kg/year). A comparison with other reports indicated that drug abuse profiles in transition countries might be different from those reported for Western Europe, in particular with respect to the comparatively increased consumption of heroin. Enhanced consumption of stimulating drugs (cocaine and ectasy) was systematically detected during weekends.

Drugs of abuse and their metabolites in the Ebro River basin: occurrence in sewage and surface water, sewage treatment plants removal efficiency, and collective drug usage estimation

Drugs of abuse and their metabolites have been recently recognized as environmental emerging organic contaminants. Assessment of their concentration in different environmental compartments is essential to evaluate their potential ecotoxicological effects. It also constitutes an indirect tool to estimate drug abuse by the population at the community level. The present work reports for the first time the occurrence of drugs of abuse and metabolites residues along the Ebro River basin (NE Spain) and also evaluates the contribution of sewage treatment plants (STPs) effluents to the presence of these chemicals in natural surface waters. Concentrations measured in influent sewage waters were used to back calculate drug usage at the community level in the main urban areas of the investigated river basin. The most ubiquitous and abundant compounds in the studied aqueous matrices were cocaine, benzoylecgonine, ephedrine and ecstasy. Lysergic compounds, heroin, its metabolite 6-monoacetyl morphine, and Delta(9)-tetradhydrocannabinol were the substances less frequently detected. Overall, total levels of the studied illicit drugs and metabolites observed in surface water (in the low ng/L range) were one and two orders of magnitude lower than those determined in effluent (in the ng/L range) and influent sewage water (microg/L range), respectively. The investigated STPs showed overall removal efficiencies between 45 and 95%. Some compounds, such as cocaine and amphetamine, were very efficiently eliminated (>90%) whereas others, such as ecstasy, methamphetamine, nor-LSD, and THC-COOH where occasionally not eliminated at all. Drug consumption estimates pointed out cocaine as the most abused drug, followed by cannabis, amphetamine, heroin, ecstasy and methamphetamine, which slightly differs from national official estimates (cannabis, followed by cocaine, ecstasy, amphetamine and heroin). Extrapolation of the consumption data obtained for the studied area to Spain points out a total annual consumption of drugs of abuse of the order of 36 tonnes, which would translate into 1100million Euros in the black market.

Predicted environmental concentrations of cocaine and benzoylecgonine in a model environmental system

A Mackay-type level II fugacity model has been used to predict the behaviour and final concentrations of cocaine (COC) and its main metabolite benzoylecgonine (BE) in a regional environmental system defined according to the European guidelines on Risk Assessment. The model takes into account the initial COC intake, partial degradation of the parent compound to BE, treatment of wastewater and environmental fate of these substances. Predicted environmental concentrations (PECs) lie in the ngL(-1) level, with the exception of the air compartment, where the concentrations are negligible. PECs in the water phase are in accordance with measured experimental concentrations in different European rivers. This case study shows that a simple level II fugacity model is suitable enough for modelling the environmental fate of high water soluble and low volatile organic compounds such as pharmaceuticals and personal care products.

Comparison of molecularly imprinted, mixed-mode and hydrophilic balance sorbents performance in the solid-phase extraction of amphetamine drugs from wastewater samples for liquid chromatography-tandem mass spectrometry determination

Recent studies have shown that amphetamines and other drugs of abuse residues occur in wastewater. Consequently, several methods have been developed for their determination by solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). However, a major drawback of these methods is the lack of selectivity during SPE that results in reduced sensitivity, due to matrix effects, and in some cases in low precision and poor accuracy. In order to tackle this problem, three different SPE alternatives have been evaluated in this work for the determination of five amphetamines: common hydrophilic balance (Oasis HLB), mixed-mode (Oasis MCX) and molecularly imprinted polymers (MIPs) sorbents. Among them, Oasis HLB showed the worst performance, as three amphetamines (MDA, MDMA and MDEA) could not be determined because of interfering signals in the LC-MS/MS chromatogram, and amphetamine recoveries could not be corrected by the use of the deuterated analogue internal standard. Oasis MCX permitted the determination of all target analytes, but with still strong signal suppression: ca. 70% signal drop with wastewater samples, which could in this case be corrected by the internal standards providing acceptable trueness (overall recoveries: 101-137%), precision (RSD: 2.0-12%) and limits of detection (LOD: 1.5-4.4 ng/L). Alternatively, MIPs rendered cleaner extracts with less matrix effects (ca. 30% signal drop), and thus lower LODs (0.5-2.7 ng/L) and even better trueness (91-114% overall recovery) and precision (1.5-4.4%RSD). The final application of the method with MIP cartridges showed the presence of MDA and MDMA in the seven analysed wastewaters at the 4-20 ng/L level.

Can cocaine use be evaluated through analysis of wastewater? A nation-wide approach conducted in Belgium

AIMS

Cocaine is the second most-used illicit drug world-wide and its consumption is increasing significantly, especially in western Europe. Until now, the annual prevalence has been estimated indirectly by means of interviews. A recently introduced and direct nation-wide approach based on measurements of the major urinary excreted metabolite of cocaine, benzoylecgonine, in wastewater is proposed.

DESIGN

Wastewater samples from 41 wastewater treatment plants (WWTPs) in Belgium, covering approximately 3,700,000 residents, were collected. Each WWTP was sampled on Wednesdays and Sundays during two sampling campaigns in 2007-08. Samples were analysed for cocaine (COC) and its metabolites, benzoylecgonine (BE) and ecgonine methylester (EME) by a validated procedure based on liquid chromatography coupled with tandem mass spectrometry. Concentrations of BE were used to calculate cocaine consumption (g/day per 1000 inhabitants) for each WWTP region and for both sampling campaigns (g/year per 1000 inhabitants).

FINDINGS

Weekend days showed significantly higher cocaine consumption compared with weekdays. The highest cocaine consumption was observed for WWTPs receiving wastewater from large cities, such as Antwerp, Brussels and Charleroi. Results were extrapolated for the total Belgian population and an estimation of a yearly prevalence of cocaine use was made based on various assumptions. An amount of 1.88 tonnes (t) per year [standard error (SE) 0.05 t] cocaine is consumed in Belgium, corresponding to a yearly prevalence of 0.80% (SE 0.02%) for the Belgian population aged 15-64 years. This result is in agreement with an earlier reported estimate of the Belgian prevalence of cocaine use conducted through socio-epidemiological studies (0.9% for people aged 15-64 years).

CONCLUSIONS

Wastewater analysis is a promising tool to evaluate cocaine consumption at both local and national scale. This rapid and direct estimation of the prevalence of cocaine use in Belgium corresponds with socio-epidemiological data. However, the strategy needs to be refined further to allow a more exact calculation of cocaine consumption from concentrations of BE in wastewater.

Monitoring of opiates, cannabinoids and their metabolites in wastewater, surface water and finished water in Catalonia, Spain

The occurrence of several opiates and cannabinoids in wastewaters and surface waters has been investigated. Most of the compounds (8 out of 11) were identified in both influent and effluents of fifteen wastewater treatment plants (WWTPs). Codeine, morphine, EDDP and methadone were detected in almost all samples with median values of 69ng/L; 63ng/L; 28ng/L and 18ng/L, respectively, whereas the main cannabinoid metabolite THC-COOH presented a median value of 57ng/L in influents. A rough estimate of heroin and cannabis consumption was performed from the analysis of target urinary metabolites in wastewater influents. Data obtained from influents of rural and urban WWTPs gave 0.07% of heroin consumption (0.67% for the largest urban WWTP) and 4% consumption of cannabinoids, respectively for the population aged between 15 and 64 years old. The presence of opiates and cannabinoids in surface waters used for drinking water production showed the presence of the same compounds identified in wastewater effluents at concentrations up to 76ng/L for codeine; 31ng/L for EDDP; 12ng/L for morphine and 9ng/L for methadone at the intake of the DWTP. A complete removal of all studied drugs present in surface water was achieved during the potabilization process except for methadone and EDDP (91% and 87% removal, respectively).

Spatial and temporal variations in the occurrence of cocaine and benzoylecgonine in waste- and surface water from Belgium and removal during wastewater treatment

Estimates of cocaine consumption are currently resulting from population surveys, consumer interviews and crime statistics. A new approach ("sewage epidemiology") based on the analysis of cocaine (COC) and its metabolite, benzoylecgonine (BE), in water samples was applied to 10 river sites and 30 wastewater treatment plants (WWTPs) in Belgium. Each river site was sampled twice, during the summer of 2007 and the winter of 2007-2008, while each WWTP was sampled on a Sunday and a Wednesday, during the summer-autumn of 2007 and the winter of 2007-2008. This sampling strategy allowed for the evaluation of spatial and seasonal variations in the occurrence of COC and BE in waste- and surface water. WWTP Brussel-Noord was sampled for 19 consecutive days to evaluate daily and weekly variations in the presence of COC and BE in wastewater. For 7 WWTPs, influent and effluent water samples were collected to investigate the removal of COC and BE during the wastewater treatment process. Analysis of water samples was performed using solid-phase extraction and liquid chromatography coupled to tandem mass spectrometry. Measured concentrations were further converted into an amount of used cocaine, called cocaine equivalents, as previously described in the literature. Results showed no significant difference in cocaine use between the investigated seasons. A constant cocaine consumption was observed during the week (Monday-Friday) with peaks during the weekend for WWTP Brussel-Noord. The COC/BE ratio in water samples was significantly higher during winter, most probably due to a slower hydrolysis of cocaine in low-temperature water. COC and BE were removed in the investigated WWTPs with a removal efficiency of >93%.