Investigation of temporal illicit drugs, alcohol and tobacco trends in Istanbul city: Wastewater analysis of 14 treatment plants

High throughput and sensitive quantitation of tobacco-specific alkaloids and nitrosamines in wastewater

Tobacco-specific alkaloids and nitrosamines are important biomarkers for the estimation of tobacco use and human exposure to tobacco-specific nitrosamines that can be monitored by wastewater analysis. Thus far their analysis has used solid phase extraction, which is costly and time-consuming. In this study, we developed a direct injection liquid chromatography-tandem mass spectrometry method for the quantification of two tobacco-specific alkaloids and five nitrosamines in wastewater. The method achieved excellent linearity (R2 > 0.99) for all analytes, with calibration ranging from 0.10 to 800 ng/L. Method limits of detection and quantification were 0.17 ng/L (N-nitrosonornicotine, NNN) and 1.0 ng/L (N-nitrosoanatabine (NAT) and NNN), with acceptable accuracy (100 % ± 20 %) and precision (± 15 %). Analyte loss during filtration was < 15 %, and the relative matrix effect was < 10 %. The method was applied to 43 pooled wastewater samples collected from three wastewater treatment plants in Australia between 2017 and 2021. Anabasine and anatabine were detected in all samples at concentrations of 5.0 - 33 ng/L and 12 - 41 ng/L, respectively. Three of the five tobacco-specific nitrosamines (NAT, NNN, and (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol) (NNAL)) were detected, in < 50 % of the wastewater samples, with concentrations nearly ten times lower than the tobacco alkaloids (< 1.0 - 6.2 ng/L). In-sewer stability of the nitrosamines was also assessed in this study, with four (NAT, NNAL, NNN, and N-nitrosoanabasine (NAB)) being stable (i.e. < 20 % transformation over 12 h in both control reactor (CR) and rising main reactor (RM) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) being moderately stable (< 40 % loss over 12 h in RM). This direct injection method provides a high-throughput approach in simultaneous investigation of tobacco use and assessment of public exposure to tobacco-specific nitrosamines.

Significant differences in usage of antibiotics in three Chinese cities measured by wastewater-based epidemiology

Antibiotic use, particularly inappropriate use by irrational prescribing or over-the-counter purchases, is of great concern for China as it facilitates the spread of antibiotic resistances. In this study, we applied wastewater-based epidemiology (WBE) to monitor the total consumption of eight common antibiotics in three cities in northern, eastern and southern China. Wastewater samples were successively collected from 17 wastewater treatment plants including weekdays and weekends spanning four seasons between 2019 and 2021. The concentration of antibiotics and their corresponding metabolites showed a significant correlation, confirming the measured antibiotics were actually consumed. Different seasonal trends in antibiotic use were found among the cities. It was more prevalent in the winter in the northern city Beijing, with the high antibiotic consumption attributed to peak influenza occurrence in the city. This is clear evidence of irrational prescription of antibiotics since it's known that antibiotics do little to treat influenza. In terms of overall consumption, Foshan is significantly lower, thanks to warmer climate and higher use of herbal tea as a prevention measure. WBE estimates of antibiotic consumption were relatively comparable with other data sources, with azithromycin as the top antibiotic measured here. The studied cities had higher WBE estimated antibiotics consumption than results of previous studies in the literature. Monitoring antibiotic use in different areas and periods through WBE in combination with complementary information, can better inform appropriate antibiotic guideline policies in various regions and nations.

Correlations between China's socioeconomic status, disease burdens, and pharmaceuticals and personal care product levels in wastewater

The presence of pharmaceutical and personal care products (PPCPs) in domestic wastewater can potentially indicate socioeconomic status and disease burdens. However, current knowledge is limited to the correlation between specific pharmaceuticals and diseases. This study aims to explore the associations between socioeconomic status, disease burdens, and PPCP levels in domestic wastewater at a national level. Samples from 171 wastewater influents across China were used to measure PPCPs, and the per capita consumption of PPCPs was calculated. Results showed that the 31 targeted PPCPs were widely present in wastewater with varying occurrence characteristics. The mean consumption levels of different PPCPs varied greatly, ranging from 0.03 to 110723.15 µg/d/capita. While there were no significant regional differences in the overall pattern of PPCP consumption, 22 PPCPs showed regional variations between Northern China and Southern China. PPCPs with similar usage purposes exhibited similar distribution patterns. Disease burden (70.1%) was the main factor affecting most PPCP consumption compared to socioeconomic factors (26.4%). Through correlation analyses, specific types of PPCPs were identified that were highly associated with socioeconomic status and disease burdens, such as hypertension-bezafibrate, brucellosis-quinolones, sulfonamides, hepatitis-triclosan, triclocarban, socioeconomic development-fluoxetine, and people's living standards-gemfibrozil. Despite some uncertainties, this study provides valuable insights into the relationship between PPCPs in domestic wastewater and socioeconomic status and human health.

Investigating alcohol consumption in China via wastewater-based epidemiology

Alcohol abuse and addiction is a public health issue of global concern. Wastewater-based epidemiology (WBE) is a forceful and effective complementary tool for investigating chemical consumption. This study examined alcohol consumption in major cities of China via WBE and compared WBE estimates with other data sources. A simple and valid ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the determination of two alcohol metabolites, ethyl glucuronide (EtG) and ethyl sulfate (EtS) in wastewater. The optimized method was applied to 62 sewage samples collected from wastewater treatment plants (WWTPs) in 31 provincial capital cities across China in the fourth quarter of 2020. The methodology established in this study was validated with the lower limit of quantification (LLOQ) up to 0.1 μg/L, good linearity in the range of 0.1-50 μg/L, intra-day and inter-day precision less than 5.58% and 5.55%, respectively, and the recoveries of the extracts were higher than 97.14%. The consumption range of alcohol estimated via WBE was 6.09 ± 4.56 ethanol/person/day (EPD) in the capital cities of China. Alcohol consumption varies significantly between cities in China, with WBE estimating lower alcohol consumption than WHO and lower than foreign countries. Investing in alcohol consumption based on WBE has great potential to accurately and efficiently estimate alcohol consumption.

Tracking methamphetamine and amphetamine consumption patterns in South Korea via enantiomeric analysis of wastewater

Wastewater-based epidemiology (WBE) has emerged as an effective method for monitoring a community's health status and lifestyle. In recent years, enantiomeric profiling has shown promise as a tool for tracing the sources of abused drugs through WBE. This study investigated amphetamine (AMP) and methamphetamine (METH) consumption in South Korea using enantiomeric analysis of untreated wastewater samples collected from 27 wastewater-treatment plants (WWTPs). Both AMP and METH were detected, with the predominant detection of S-(+)-METH indicating widespread illegal use of METH, which is primarily produced by a clandestine synthesis procedure that involves the reduction of ephedrine/pseudoephedrine. Most AMP/METH ratios in the samples were consistent with the expected METH excretion profile, indicating that the presence of AMP was primarily due to METH metabolism. However, R-(-) AMP was detected in 18.5 % and 25.9 % of wastewater samples in winter and spring, respectively, and the high AMP/METH ratio (>0.27) indicated potential AMP abuse. By differentiating between the sources of AMP and METH in wastewater, enantiomeric analysis could help authorities to target and address specific drug-abuse issues affecting the population more effectively.

Fluorinated-Squaramide Covalent Organic Frameworks for High-Performance and Interference-Free Extraction of Synthetic Cannabinoids

Synthetic cannabinoids (SCs), one of the largest groups of new psychoactive substances (NPSs), have emerged as a significant public health threat in different regions worldwide. Analyzing SCs in water samples is critical to estimate their consumption and control. However, due to their low background concentration and the coexistence of complex matrix, the selective and effective enrichment of SCs is still challenging. In this study, a series of fluorinated-squaramide-based covalent organic frameworks (COF: FSQ-2, FSQ-3, and FSQ-4) are synthesized, and the as-prepared FSQ-4 exhibits strong affinity to different SCs. The proper pore size (1.4 nm) and pre-located functional groups (hydrogen-bond donors, hydrogen-bond acceptors, and fluorophilic segments) work synergistically for efficient SCs capture. Remarkably, when coupled FSQ-4 with solid-phase microextraction (SPME), trace-level (part per trillion, 10-9 ) determination of 13 SCs can be easily achieved, representing one of the best results among NPS analyses, and the excellent extraction performance can be maintained under various interfering conditions.

Trends and challenges in analytical chemistry for multi-analysis of illicit drugs employing wastewater-based epidemiology

Wastewater-based epidemiology (WBE) for quantification of illicit drug biomarkers (IDBs) in wastewater samples is an effective tool that can provide information about drug consumption. The most commonly quantified IDBs belong to different chemical classes, including cocaine, amphetamine-type stimulants, opioids, and cannabinoids, so the different chemical properties of these molecules pose a challenge in the development of analytical methods for multi-analyte analysis. Recent workflows include the steps of sampling and storage, sample preparation using solid-phase extraction (SPE) or without extraction, and quantification of analytes employing gas or liquid chromatography coupled with mass spectrometry. The greatest difficulty is due to the fact that wastewater samples are complex chemical mixtures containing analytes with different chemical properties, often present at low concentrations. Therefore, in the development of analytical methods, there is the need to simplify and optimize the analytical workflows, reducing associated uncertainties, analysis times, and costs. The present work provides a critical bibliographic survey of studies published from the year 2020 until now, highlighting the challenges and trends of published analytical workflows for the multi-analysis of IDBs in wastewater samples, considering sampling and sample preparation, method validation, and analytical techniques.

Investigation on consumption of psychoactive substances and their ecological risks using wastewater-based epidemiology: a case study on Qinghai-Tibet Plateau

The Qinghai-Tibet Plateau is the third pole of the world, and information on the consumption of psychoactive substances (PSs) in this area is scarce. In this study, we selected Qinghai Province as the research area, and the per capita consumption and prevalence of PSs were investigated using wastewater-based epidemiology. Samples from 17 wastewater treatment plants (WWTPs) in 5 major cities in Qinghai Province were monitored, and 11 PSs were detected by ultra-high performance liquid chromatography-tandem mass spectrometry. Results showed that the target compounds were detected in all samples, with relatively high concentrations of ephedrine (2.1-4825.3 ng/L) and methamphetamine (1.5-295.7 ng/L). The consumption of methamphetamine in Xining City, Haidong City, and Haixi City was up to 78.4, 16.8, and 21.2 mg/1000 inh/d (the PS consumption per 1000 inhabitants in 1 day), respectively, higher than that in the other two cities, which was the result of the different consumption patterns and its relationship with the economic levels of each city. High consumption of methadone (47.9 mg/1000 inh/day) was found in Xining City, which might be related to the methadone maintenance therapy sites in the city. Methamphetamine was the most prevalent drug, with the prevalence ranging from 0.003 (Guoluo) to 0.197% (Xining), and the prevalence of other PSs was low. The ecological risk assessment of PSs in the effluent of WWTPs showed that methadone exerted a low risk to aquatic organisms in three sites, while other substances posed potential risk or no risk. However, the long-term effect of PSs cannot be ignored.

National Wastewater Reconnaissance of Analgesic Consumption in Australia

A wastewater-based epidemiology (WBE) method is presented to estimate analgesic consumption and assess the burden of treated pain in Australian communities. Wastewater influent samples from 60 communities, representing ∼52% of Australia's population, were analyzed to quantify the concentration of analgesics used to treat pain and converted to estimates of the amount of drug consumed per day per 1000 inhabitants using pharmacokinetics and WBE data. Consumption was standardized to the defined daily dose per day per 1000 people. The population burden of pain treatment was classified as mild to moderate pain (for non-opioid analgesics) and strong to severe pain (for opioid analgesics). The mean per capita weighted total DDD of non-opioid analgesics was 0.029 DDD/day/person, and that of opioid-based analgesics was 0.037 DDD/day/person across Australia. A greater burden of pain (mild to moderate or strong to severe pain index) was observed at regional and remote sites. The correlation analysis of pain indices with different socioeconomic descriptors revealed that pain affects populations from high to low socioeconomic groups. Australians spent an estimated US $3.5 (AU $5) per day on analgesics. Our findings suggest that WBE could be an effective surveillance tool for estimating the consumption of analgesics at a population scale and assessing the total treated pain burden in communities.

Consumption of common illicit drugs in twenty-one cities in southwest China through wastewater analysis

Wastewater-based epidemiology (WBE) was applied to estimate illicit drugs consumption at a provincial scale in southwest China. A large-scale wastewater sampling campaign was carried out from October to November in 2021 in 156 different wastewater treatment plants (WWTPs). Two 24-h composite influent wastewater samples were collected in each WWTP. Concentrations of 11 illicit drugs or their metabolites were determined using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Benzoylecgonine, cocaine, 6-monoacetylmorphine, norketamine, 3,4-methylenedioxymethamphetamine (MDMA), and MDA were not detected in any of the wastewater samples. Methamphetamine and morphine were detected in >84% of samples, while ketamine was found in about 6% of the samples. The city-specific population-weighted consumption of methamphetamine and ketamine were in the range of 0.6-49.7 and N.D.-7.0 mg 1000 inh^-1 day^-1, respectively, with provincial population-weighted values of 22.6 and 2.4 mg 1000 inh^-1 day^-1 in southwest China. The city-specific load of morphine varied from 3.2 to 10.2 mg 1000 inh^-1 day^-1, with provincial population-weighted load of 6.7 mg 1000 inh^-1 day^-1. Taking into account therapeutic use of morphine and codeine, the provincial heroin consumption was estimated to be 10.3 mg 1000 inh^-1 day^-1, ranging from 1.7 to 18.5 mg 1000 inh^-1 day^-1 in 21 cities. Overall, the patterns of illicit drugs use were similar across southwest China, with high prevalence of methamphetamine and heroin, but relatively low use of ketamine. These findings could provide accurate drugs consumption information for timely identifying potential hotspots of illicit drugs use in southwest China.

Monitoring of changes in illicit drugs, alcohol, and nicotine consumption during Ramadan via wastewater analysis

Illicit drug use is a global problem imposing social, economic, and health burdens on society. Wastewater-based epidemiology is an approach based on calculating the consumption of substances in the target population by analyzing the concentrations of human metabolic excretion products of licit and illicit substances in wastewater. This study estimated the changes in illicit drugs (cocaine, amphetamine, methamphetamine, ecstasy (3,4-Methylenedioxymethamphetamine), heroin, and marijuana (THC)), alcohol, and nicotine consumption in Adana Province during Ramadan compared to normal periods using wastewater-based epidemiology. An overall decrease was observed during the Ramadan Period, most strongly for ecstasy (29%) followed by heroin (19%). For cocaine, the variation was the slightest (8.6%). The differences were statistically significant for ecstasy, heroin, nicotine, and alcohol but not for cocaine, amphetamine, methamphetamine, and marijuana. This study is the first to show changes in the use of illicit drugs, alcohol, and nicotine under the influence of religious beliefs. In addition, there is limited data about illicit drugs, alcohol and nicotine abusers/users in Ramadan. This study provides information on the literature on this subject.

Evaluating the impact of COVID-19 countermeasures on alcohol consumption through wastewater-based epidemiology: A case study in Belgium

Wastewater-based epidemiology (WBE) is a complementary approach to monitor alcohol consumption in the general population. This method measures concentrations of xenobiotic biomarkers (e.g., ethyl sulphate) in influent wastewater (IWW) and converts these to population-normalized mass loads (PNML, in g/day/1000 inhabitants) by multiplying with the flow rate and dividing by the catchment population. The aims of this case study were to: (i) investigate temporal trends in alcohol use during the COVID-19 pandemic; and (ii) measure the effect of policy measures on alcohol consumption. Daily 24-h composite IWW samples (n = 735) were collected in the wastewater treatment plant of the university city of Leuven (Belgium) starting from September 2019 to September 2021. This is the first study that investigates alcohol use through WBE for a continuous period of two years on a daily basis. Mobile phone data was used to accurately capture population fluxes in the catchment area. Data was evaluated using a time series based statistical framework to graphically and quantitatively assess temporal differences in the measured PNML. Different WBE studies observed temporal changes in alcohol use during the COVID-19 pandemic. In this study, the PNML of ethyl sulphate decreased during the first lockdown phase, potentially indicating that less alcohol was consumed at the Leuven area during home confinement. Contrastingly, alcohol use increased after the re-opening of the catering industry. Additionally, a decrease in alcohol use was observed during the exam periods at the University of Leuven and an increase during the holiday periods. The present study shows the potential of WBE to rapidly assess the impact of some policy measures on alcohol consumption in Belgium. This study also indicates that WBE could be employed as a complementary data source to fill in some of the current knowledge gaps linked to lifestyle behavior.

Assessing changes in nicotine consumption over two years in a population of Hanoi by wastewater analysis with benchmarking biomarkers

Monitoring the actual change in consumption of nicotine (a proxy for smoking) in the population is essential for formulating tobacco control policies. In recent years, wastewater-based epidemiology (WBE) has been applied as an alternative method to estimate changes in consumption of tobacco and other substances in different communities around the world, with high potential to be used in resource-scarce settings. This study aimed to conduct a WBE analysis in Hanoi, Vietnam, a lower-middle-income-country setting known for high smoking prevalence. Wastewater samples were collected at two sites along a sewage canal in Hanoi during three periods: Period 1 (September 2018), Period 2 (December 2018-January 2019), and Period 3 (December 2019-January 2020). Concentrations of cotinine, 3-hydroxycotinine, and nicotine ranged from 0.73 μg/L to 3.83 μg/L, from 1.09 μg/L to 5.07 μg/L, and from 0.97 μg/L to 9.90 μg/L, respectively. The average mass load of cotinine estimated for our samples was 0.45 ± 0.09 mg/day/person, which corresponds to an estimated daily nicotine consumption of 1.28 ± 0.25 mg/day/person. No weekly trend was detected over the three monitoring periods. We found the amount of nicotine consumption in Period 1 to be significantly lower than in Period 2 and Period 3. Our WBE estimates of smoking prevalence were slightly lower than the survey data. The analysis of benchmarking biomarkers confirmed that cotinine was stable in the samples similar to acesulfame, while paracetamol degraded along the sewer canal. Further refinement of the WBE approach may be required to improve the accuracy of analyzing tobacco consumption in the poor sewage infrastructure setting of Vietnam.

Preparation and application of nano petal-shaped covalent organic frameworks modified polystyrene-divinylbenzene- glycidylmethacrylate microspheres for the extraction of illicit drugs from wastewater

A novel nano petal-shaped covalent organic frameworks modified magnetic polystyrene-divinylbenzene-glycidylmethacrylate (NP-COF@Mag-PS/DVB/GMA) microsphere has been synthesized. It is a perfect combination of high productivity of PS/DVB/GMA microspheres and excellent enrichment efficiency of COF particles, and the excellent properties of NP-COF@Mag-PS/DVB/GMA microspheres are characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) and X-ray photoelectron spectroscopy (XPS). The sorbent can extract illicit drugs via the reverse-phase interactions provided by benzene ring on the polymer backbone and the hydrogen bonding interactions provided by functional group (-NH-) on the COF particles. Based on using NP-COF@Mag-PS/DVB/GMA as sorbents, an easiness-to-handle of magnetic dispersive solid phase extraction (Mag-dSPE) procedure is proposed for the simultaneous preconcentration of 12 illicit drugs from wastewater. The obtained results show high extraction efficiency of NP-COF@Mag-PS/DVB/GMA to illicit drugs with recoveries between 81.6 and 116%. Furthermore, a liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) method for the determination of 12 illicit drugs from wastewater at sub-ppt levels has been proposed and validated with the pretreatment of samples by Mag-dSPE. The limits of quantification (LOQs) for the 12 illicit drugs are between 0.40 and 4.90 ng/L. Validation results on linearity, specificity, trueness and precision, as well as on application to the analysis of 12 illicit drugs in ten real samples demonstrate the applicability to environment monitoring analysis.

Analysis of synthetic cannabinoids in wastewater of major cities in China

Synthetic cannabinoids (SCs) could pose serious health risks to its users. It is necessary to monitor its community consumption. Wastewater-based epidemiology is a potentially useful approach in this regard. However, limited research has been conducted to investigate the occurrence of SCs in wastewater. In this study, liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was optimized to analyze 8 SCs and metabolites (in total 16 analytes) in wastewater. The limit of quantification for this method for certain analytes in wastewater was as low as 0.03 ng L^-1. The validated method was used to examine the stability of the analytes under different conditions and to examine their occurrence in wastewater collected from 31 major cities across China. The overwhelming majority of the analytes were stable within 24 h, even at room temperature. However, 5-fluoro MDMB-PICA and MDMB-4en-PINACA butanoic acid metabolite showed significant degradation within 120 days even when stored at -20 °C or -80 °C. At least one cannabinoid or their metabolite was detected in 21 cities. In the city with the highest detection rate, at least one synthetic cannabinoid or metabolite was detected in 95% of samples of the city. MDMB-4en-PINACA butanoic acid metabolite had the highest detection frequency (in 13.4% of the samples). These results indicated that SCs were used in a significant number of Chinese cities. A few parent drugs (MDMB-4en-PINACA, ADB-BUTINACA, 5-fluoro MDMB-PICA, 4-fluoro MDMB-BUTINACA) were detected in a small fraction of wastewater samples, possibly due to release from manufacturing of these cannabinoids or illegal addition of electronic cigarettes.

Monitoring and ecological risk of illegal drugs before and after sewage treatment in an area

In this study, the occurrence of illicit drugs and their metabolites in the sewerage systems and in the influent and effluent of wastewater treatment plant (WWTP) in Konya, Turkey, was presented. The drug removal efficiencies of the central WWTP were investigated. Potential ecotoxicological risks for algae, fish, and Daphnia magna in the receiving environments were also evaluated. The highest estimated mean illicit drug use was obtained for cannabis (marijuana) at 280 ± 12 mg/day/1000 inhabitants and 430 ± 20 g/day/1000 inhabitants (15-64 years). Amphetamine was found to be the second most consumed drug of abuse. While cannabis and ecstasy consumption values were higher during the weekend, cocaine use dominated on weekdays. The removal efficiencies for THC-COOH and THC-OH were 100% in the WWTP. The average removal of cocaine, amphetamine, methamphetamine, MDMA, MDA, and methadone varied between 46 ± 7 and 87 ± 3%. The maximum concentration level of MDMA found can pose some low risk for Daphnia magna. The rest of the compounds detected in effluents did not show any toxic effects on fish, Daphnia magna, or algae. However, when the cumulative estimated risk quotient values were evaluated, there might be a low risk for Daphnia magna and algae in the receiving environment.

Monitoring geographical differences in illicit drugs, alcohol, and tobacco consumption via wastewater-based epidemiology: Six major cities in Turkey

A national wastewater-based epidemiology (WBE) monitoring campaign has been initiated to determine the trends in drug consumption in Turkey since 2019. This study aimed to present the wastewater monitoring results for four periods in 2019 for six major cities with 17 wastewater treatment plants. The study investigated heroin (HER), amphetamine (AMP), methamphetamine (METH), cocaine (COC), 3,4-methylenedioxymethamphetamine (MDMA), cannabis, alcohol, and tobacco to understand the temporal and geographical drug consumption trends. The results indicated a trend of regular cannabis use in all the cities. Considering geographical variations, the drug usage trends were not homogeneous within the country for any of the investigated drugs, except cannabis. HER consumption was predominant in Denizli (1042.48 mg/1000 inh/day), while İzmir and Antalya (154.10 and 79.56 mg/1000 inh/day, respectively) topped for COC consumption. Aydın had the highest consumption levels of AMP (90.03 mg/1000 inh/day) and METH (358.13 mg/1000 inh/day), while MDMA consumption was the highest in Samsun (157.64 mg/1000 inh/day). Tobacco consumption was high in Aydın (8791.69 mg/1000 inh/day) and Antalya (5375.17 mg/1000 inh/day), whereas alcohol consumption was higher in Bursa than in the other cities (53434.61 mL/1000 inh/day). There were no statistically significant differences in the weekend consumption levels of the investigated drugs among these six cities. Although this study included the results of 1 year of consumption monitoring, the data confirms internationally published information on the drug trafficking routes of conventional drugs in this region, especially the Heroin-Balkan route. Results from further sampling will enable accurate evaluation of global drug consumption and trafficking, in addition to alcohol and tobacco use.

Simultaneous Determination of Seven Antibiotics and Five of Their Metabolites in Municipal Wastewater and Evaluation of Their Stability under Laboratory Conditions

The selection and spread of antibiotic resistance poses risks to public health by reducing the therapeutic potential of antibiotics against human pathogens. Wastewater-based epidemiology (WBE) is potentially the most reliable approach to estimate antibiotics use. Previous WBE studies used parent antibiotics as biomarkers, which may lead to overestimation since parent antibiotics may be directly disposed of. Using metabolites as biomarkers can avoid this drawback. This study developed a simultaneous solid-phase extraction coupled with ultra-high-performance liquid chromatography tandem mass spectrometry method for analyzing 12 antibiotics and human metabolites in wastewater to help assess health risk. Optimum conditions were achieved using a PEP cartridge at pH 3.0. The extraction efficiencies were 73.3~95.4% in influent and 72.0~102.7% in effluent for most of the target analytes. Method detection limit ranged from 0.1 to 1.5 ng/L for influent wastewater and 0.03 to 0.7 ng/L for effluent wastewater. A stability experiment showed that sulfonamide parents and their metabolites were stable at 4 °C, −20 °C and −80 °C, while macrolides metabolites were more stable than their corresponding parents at 4 °C and −20 °C. Finally, the method was applied to measure these analytes in wastewater samples collected from three Beijing WWTPs and to derive apparent removal rates. All metabolites were detected in wastewater samples with concentrations ranging from 1.2 to 772.2 ng/L in influent, from <MDL to 235.6 ng/L in effluent. The apparent removal rates of five metabolites were above 72.6%. These results set a solid foundation for applying WBE to evaluate antibiotics use and its public health effects.

Occurrence of areca alkaloids in wastewater of major Chinese cities

Areca nut is a widely used psychoactive product that can cause multiple health problems, such as oral and pharyngeal cancers. Therefore, it is important to estimate areca nut use and the exposure levels of areca alkaloids that are responsible for its health effects. China is a major producer of areca nut and has a large number of areca nut chewers. In this study, occurrence of areca alkaloids and metabolites in wastewater of major cities across China was examined via wastewater-based epidemiology (WBE). Arecoline, arecaidine, and their metabolite, N-methylnipecotic acid (NMNA) were detected in the overwhelming majority of wastewater samples, with concentrations up to several μg/L. In contrast, guvacoline was only occasionally detected and guvacine was below detection limit in all samples, possibly due to their low contents in areca nut products, low excretion rates, and/or low stability in sewer systems. Strong positive correlations existed between arecoline, arecaidine, and NMNA concentrations. In addition, their loads were much higher in Central and Southern China. This geographic pattern is consistent with previous survey results on prevalence of areca nut chewing. These results indicate that WBE is a potentially useful method to monitor areca nut consumption and to estimate the exposure levels of areca alkaloids.

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.