Metabolites In Surface Waters Research Articles

Guidance document on the impact of water treatment processes on residues of active substances or their metabolites in water abstracted for the production of drinking water.

This guidance document provides a tiered framework for risk assessors and facilitates risk managers in making decisions concerning the approval of active substances (AS) that are chemicals in plant protection products (PPPs) and biocidal products, and authorisation of the products. Based on the approaches presented in this document, a conclusion can be drawn on the impact of water treatment processes on residues of the AS or its metabolites in surface water and/or groundwater abstracted for the production of drinking water, i.e. the formation of transformation products (TPs). This guidance enables the identification of actual public health concerns from exposure to harmful compounds generated during the processing of water for the production of drinking water, and it focuses on water treatment methods commonly used in the European Union (EU). The tiered framework determines whether residues from PPP use or residues from biocidal product use can be present in water at water abstraction locations. Approaches, including experimental methods, are described that can be used to assess whether harmful TPs may form during water treatment and, if so, how to assess the impact of exposure to these water treatment TPs (tTPs) and other residues including environmental TPs (eTPs) on human and domesticated animal health through the consumption of TPs via drinking water. The types of studies or information that would be required are described while avoiding vertebrate testing as much as possible. The framework integrates the use of weight-of-evidence and, when possible alternative (new approach) methods to avoid as far as possible the need for additional testing.

Detection of secondary cyanobacterial metabolites using LC-HRMS in Lake Karaoun

Harmful algal blooms events have been reported worldwide and during the last decades are occurred with increasing frequency and intensity due to the climate change and the high inputs of nutrients in freshwaters from anthropogenic activities. During blooms cyanobacteria release in water their toxic secondary metabolites, known as cyanotoxins, along with other bioactive metabolites. Due to the negative impacts of these compounds on aquatic ecosystems and public health, there is an urgent need to detect and identify known and unknown cyanobacterial metabolites in surface waters. In the frame of the present study, a method based on liquid chromatography - high resolution mass spectrometry (LC-HRMS) was developed to investigate the presence of cyanometabolites in bloom samples from Lake Karaoun, Lebanon. Data analysis was performed using Compound Discoverer software with related tools and databases in combination to the CyanoMetDB mass list for detection, identification and structural elucidation of the cyanobacterial metabolites. In the course of this study, 92 cyanometabolites were annotated including 51 cyanotoxins belonging to microcystins, 15 microginins, 10 aeruginosins, 6 cyclamides, 5 anabaenopeptins, a cyanopeptolin, the dipeptides radiosumin B and dehydroradiosumin, the planktoncyclin and a mycosporine–like amino acid. Out of them, 7 new cyanobacterial metabolites, the chlorinated MC-ClYR, [epoxyAdda5]MC-YR, MC-LI, aeruginosin 638, aeruginosin 588, microginin 755C and microginin 727 were discovered. Moreover, the presence of anthropogenic contaminants was recorded indicating the pollution of the lake and emphasizing the need for assessment of the co-occurrence of cyanotoxins, other cyanobacterial metabolites and other compounds hazardous to the environment. Overall, results prove the suitability of the proposed approach for the detection of cyanobacterial metabolites in environmental samples but also highlight the necessity of spectral libraries for these compounds, considering the absence of their reference standards.

Simultaneous and sensitive analysis of glyphosate, glufosinate, and their metabolites in surface water by HPLC-ICP-MS/MS.

Organophosphorus pesticides such as glyphosate and glufosinate are used worldwide, and environmental regulatory values are being adopted in many countries due to their potential toxicity. In the present work, a pretreatment-free analytical method is established in which these two compounds with their metabolites are isolated fromeach other by anion-exchange HPLC using ammonium acetate (70mM, pH 3.7) as eluent, and theyaredetected by triple quadrupole ICP-MS. Very low detection limits of 0.03-0.17μg L-1 are acquired through the detection of P+ as PO+ via oxygen reaction mode, and quantitative recovery was obtained from the spike-recovery test on river water samples containing phosphate ion as an isobaric interferent. In addition, a constant sensitivity per molar concentration was achieved regardless of the compounds due to the powerful ion source of ICP-MS. This property suggests that semi-quantitative analysis of unknown P-bearing compounds is possible from one calibration curve.

Antibiotics in global rivers

<p indent="0mm">Antibiotics have received extensive attention due to their sophisticated effects on human health and ecosystems. However, there is an extreme scarcity of information on composition, content, geographic distribution, and risk of riverine antibiotics at a large spatial scale. Based on a systematic review of over 600 pieces of literature (1999–2021), we established a global dataset containing more than 90,000 records covering 169 antibiotics and their metabolites in surface water and sediment across 76 countries. The occurrence of prioritized antibiotics largely depended on socioeconomic developmental levels, and the current “hotspots” of polluted rivers were found mostly in less developed countries or emerging economies (e.g., some in Africa, South America, and Asia). By developing the screening protocol for risk-based prioritization of antibiotics, we advanced a rank list of antibiotics for guiding formulation of region-specific strategies, which highlighted the importance of whole life cycle management of antibiotics in health maintenance of the world’s rivers.

Haloperidol alters the behavioral, hematological and biochemical parameters of freshwater African catfish, Clarias gariepinus (Burchell 1822)

The presence of drugs and their metabolites in surface waters and municipal effluents has been reported in several studies, but their impacts on aquatic organisms are not yet well studied. The present study investigated the effects of exposure to the antipsychotic drug, haloperidol on the behavioral, hematological and biochemical parameters in juvenile Clarias gariepinus. The fishes were exposed to 0.12, 0.24 and 0.48 mg/L haloperidol for 15 days and later withdrawn from the toxicant and allowed to recover for 5 days. Blood was sampled on days 1, 5, 10, 15, and after the 5-day recovery for hematological and biochemical analysis. The pack cell volume (PCV), red blood cells (RBC), hemoglobin (Hb), reticulocytes and lymphocyte counts were significantly reduced in the exposed fish. The neutrophil counts were increased while that of monocytes, basophils and eosinophils were not affected by the drug. The mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) were not different from the control on exposure to the drug. The activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and acid phosphatase (ACP); and serum creatinine, bile acid and bilirubin were increased on 15-day exposure to the drug. The activity of the clotting factor fibrinogen was reduced compared to the control after exposure to the drug. Haloperidol at concentrations used on 15-day exposure were toxic to fish, but the effect appeared short-lived, as it dissipated on 5-day withdrawal from the drug. While further studies are needed to ascertain the impact of prolonged exposure to environmentally relevant concentrations, caution is advised to avoid eco-toxicological damage to aquatic organisms.

Pollution level, distribution characteristics and risk assessment of psychotropic substances and their metabolites in surface water of Lakes Gaoyou, Baoying and Shaobo, Jiangsu Province

为探究典型精神类药物及其代谢产物在高宝邵伯湖——宝应湖、高邮湖和邵伯湖表层水体的污染水平、分布特征及生态风险，利用超高效液相色谱-串联质谱法，对研究区域18个采样点位表层水体中3类（抗抑郁药物、抗癫痫药物和抗精神病药物）21种精神类药物及其代谢产物的浓度水平进行检测分析.结果表明，除奥卡西平外，其余20种典型精神类药物及代谢产物均有不同程度地检出，检出率范围为22.2%～100%，总检出浓度范围为1.4～224.5 ng/L.其中抗精神病药物利培酮检出浓度最高，浓度范围为0.1～64.1 ng/L.不同采样点精神类药物及其代谢产物的浓度存在空间差异，呈现邵伯湖和高邮湖南部浓度较高，高邮湖北部和宝应湖浓度较低的趋势.由聚类分析可知，点位S1、S7单独形成聚类，浓度分别为175.7和102.9 ng/L.对精神类药物及其代谢产物的来源分析发现，污水处理厂、生活污水和农业废水排放可能是高宝邵伯湖地表水中精神类药物及其代谢产物的主要来源.采用风险商值法（risk quotient，RQ）进行生态风险评估，结果表明高宝邵伯湖表层水体中卡马西平和环氧卡马西平对水生生物具有高风险（RQ>1）.精神类药物及其代谢产物在环境中持续性赋存的风险需引起重视.;To investigate the pollution level, distribution characteristic and ecological risk of psychotropic substances and their metabolites in Lakes Gaoyou, Baoying and Shaobo, Jiangsu Province, 18 water samples were collected. The concentrations of 21 psychotropic drugs and their metabolites in three classes:antidepressants, antiepileptics and antipsychotics were analyzed by ultra- high-performance liquid chromatography- triple quadrupole tandem mass spectrometry. The results indicated, in addition to oxcarbazepine, 20 typical drugs and their metabolites were detected at 18 sampling sites with the detection rates of 22.2%-100%, and the total concentration ranged from 1.4 to 224.5 ng/L. Among the detected substances, the concentration of risperidone (0.1-64.1 ng/L) was the highest. Spatial differences in the concentrations of psychotropic substances and their metabolites existed at different sampling sites, showing a trend of higher concentrations in Lake Shaobo and the southern part of Lake Gaoyou and lower concentrations in the northern part of Lakes Gaoyou and Baoying. The cluster analysis showed that point S1 and S7 formed separate clusters with concentrations of 175.7 ng/L and 102.9 ng/L, respectively. The source analysis found that wastewater treatment plants, domestic sewage and agriculture discharge may be the principal sources of the psychotropic substances and their metabolites. The risk quotient method showed that the RQ values for carbamazepine and oxcarbazepine were greater than 1 and were of high risk to aquatic organisms. The risk of psychotropic substances and their metabolites in the environment still needs attention.

Gas Chromatography Multiresidue Method for Enantiomeric Fraction Determination of Psychoactive Substances in Effluents and River Surface Waters

Determination of psychoactive substances (PAS) and/or their metabolites in surface waters is crucial for environmental risk assessment, and disclosure of their enantiomeric fractions (EF) allows discrimination between consumption, direct disposal, and synthesis pathways. The aim of this study was to develop and validate an indirect method by gas chromatography coupled to mass spectrometry (GC–MS) based on derivatization using (R)-(−)-α-methoxy-α-(trifluoromethyl) phenylacetyl chloride as chiral derivatization reagent, for enantiomeric quantification of amphetamine (AMP), methamphetamine (MAMP), 3,4-methylenedioxymethamphetamine (MDMA), norketamine, buphedrone (BPD), butylone, 3,4-dimethylmethcathinone (3,4-DMMC), 3-methylmethcathinone, and quantification of 1-benzylpiperazine and 1-(4-metoxyphenyl)-piperazine. The method allowed to evaluate the occurrence, spatial distribution, and the EF of the target chiral PAS in Portuguese surface waters and in effluents from 2 wastewater treatment plants (WWTP). For that, water samples were pre-concentrated by solid phase extraction using OASIS® MCX cartridges, derivatized and further analyzed by GC–MS. Both enantiomers of AMP, (R)-MDMA, (S)-MAMP, and the first eluted enantiomer of BPD (configuration not assigned) were found in surface waters, while effluent samples showed both enantiomers of MDMA, (S)-MAMP, (R)-AMP, and the first eluted enantiomer of BPD and 3,4-DMMC. According to our knowledge, this is the first multiresidue analytical method by CG–MS enrolling cathinones, amphetamines, and piperazines. The presence of illicit synthetic cathinones in Douro River estuary is here reported for the first time, along with other amphetamine derivatives. The potential of the method to monitor consumption of the target PAS was demonstrated.

Multibiomarker assessment in zebrafish Danio rerio after the effects of malathion and chlorpyrifos

Nowadays, organophosphates appear to be among the most used pesticides all over the world. Their amounts and amounts of their metabolites in surface water are expected to increase in the near future. In the light of potential organelles impairment, this work aims to investigate the effects of chlorpyrifos and malathion in environmentally relevant concentration on morphological and functional traits of zebrafish mitochondria and lysosomes. Adult zebrafish were exposed to widely used organophosphate pesticides namely malathion (5 and 50 µg L−1) and chlorpyrifos (0.1 and 3 µg L−1) for 14 days. The comprehensive set of biochemical markers that reflect oxidative/carbonyl/nitrosative stress and cytotoxicity (mitochondria swelling, lysosomal membrane stability, and cell damage) was determined in fish liver. Chlorpyrifos and malathion in both concentrations were found to affect mitochondria and lysosome membranes: They caused a substantial decline in neutral red retention and an increase in mitochondria swelling. Also, the concentration-dependent enhancement of lactate dehydrogenase in blood was depicted. Even low pesticide concentrations were able to promote apoptosis and stimulated overproduction of methylglyoxal as reactive carbonyl species. We also revealed that reactive nitrogen species were sparked by organophosphates. This effect occurs only in animals treated with higher insecticides concentration. Moreover, the pesticides induced oxidative stress response measured by increasing of reactive oxygen species level (only after chlorpyrifos), as well as by variation in total antioxidant capacity with signs of deeper injury after chlorpyrifos exposure. The integrative biomarker response (IBR) index calculation supports the hypothesis that chlorpyrifos was significantly more toxic to zebrafish than malathion. Our study suggests that zebrafish markers can serve as a sensitive transferential model for evaluating mitochondrial and lysosomal toxicity of pesticides and extrapolating results to mammalian and human.

Phototransformation kinetics of cyanobacterial toxins and secondary metabolites in surface waters

BackgroundCyanobacteria and their toxins occur in high concentrations during the so-called bloom events in surface waters. To be able to assess the risks associated with cyanobacterial blooms, we need to understand the persistence and fate processes of these toxins and other bioactive metabolites. In this study, we investigated the photochemical fate of 54 cyanopeptides extracted from two strains of Microcystis aeruginosa (PCC7806 and UV006), Planktothrix rubescens, and Dolichospermum flos aquae. We determined half-lives during sunlight exposure in lake water and inspected the effect of pH on transformation kinetics for 27 microcystins, 8 anabaenopeptins, 14 cyanopeptolins, 2 cyclamides, and 3 aeruginosins.ResultsFor cyanopeptides from D. flos aquae and P. rubescens, we observed the highest removal of 28 and 26%, respectively, after 3-h sunlight exposure. Most cyanopeptides produced by the two M. aeruginosa strains were rather persistent with only up to 3% removal. The more reactive cyanopeptides contained amino acids known to undergo phototransformation, including methionine and tyrosine moieties or their derivatives. Photochemical half-lives of 14 tyrosine-containing cyanopeptides decreased by one order of magnitude from nearly persistent conditions at pH 7 (half-life > 70 h) to shorter half-lives at pH 10 (< 10 h).ConclusionsMore work is needed to distinguish the contribution of different photochemical reaction pathways including the contributions to the pH effect. To the best of our knowledge, this is the first assessment of transformation kinetics of such a wide range of cyanopeptides. The abundant and persistent cyanopeptides that have not been studied in detail yet should be prioritized for the evaluation of their ecosystem and human health risks and for their abatement during drinking water treatment.

Adsorptive removal of vitamin B6 and ciprofloxacin using polyurethane foam in pure and pharmaceutical preparations: Kinetic and equilibrium studies

AbstractThe release of active pharmaceutical ingredients and their metabolites in surface waters and groundwater with insufficiently treated wastewaters nowadays may be a global environmental concern. In this study, simple, inexpensive, and solid phase procedure has been developed for the removal of pyridoxine hydrochloride (vitamin B6, PDX) and ciprofloxacin (CPX) onto polyurethane foam (PUF) using the batch mode technique. PUF was characterized using scanning electron microscopy and FT‐IR spectroscopy. The batch experiments indicated optimum conditions for the adsorption process at pH 5.6 for PDX and CPX. The optimum contact time to reach its best removal is 30 min for the removal of both drugs and the sorbent amount at 1.0 and 1.5 g for PDX and CPX, respectively. It was found that the experimental data for the adsorption of PDX fit well into Langmuir model with R2 values (0.979). Whereas the adsorption of CPX follows Freundlich model with R2 value (0.914). Adsorption process undergoes pseudo‐first‐order kinetic as proved by the high value of R2 (0.973) and (0.956) for PDX and CPX, respectively. Experimental results have proven that PUF has a great potential for the removal of both drugs with maximum removal efficiency 50 and 98% for PDX and CPX, respectively.

Sensitive, rapid and non-derivatized determination of glyphosate, glufosinate, bialaphos and metabolites in surface water by LC–MS/MS

Glyphosate, glufosinate and bialaphos are widely used worldwide as herbicides. It has been reported that they can transfer into environmental water bodies, posing health threat to human. Thus, a sensitive and rapid analysis methodology for these compounds and corresponding metabolites is highly necessary. Due to their zwitterionic nature, previously reported methods for determination of these compounds generally require derivatization. Also, preconcentration step is typically needed in order to obtain high sensitivity. Herein, we report a very convenient and sensitive assay for these herbicides as well as corresponding metabolites in surface water. With judicious tuning of chromatographic conditions, very low LODs were achieved without derivatization or preconcentration step. The LODs were 0.15 ng mL−1 for glyphosate, glufosinate, MPPA and bialaphos, 0.1 ng mL−1 for AMPA. The LOQs were 0.5 ng mL−1 for glyphosate, glufosinate, MPPA and bialaphos, 0.3 ng mL−1 for AMPA. Recoveries ranging in 90.3–102.8% were obtained. The intra-day relative standard deviations (RSDs) ranged in 4.0–5.6%, while the inter-day RSDs ranged in 4.7–6.7%. The ME (n = 6) ranged from 92.6 to 97.2%. This assay was applied to real samples of surface water. This method is very promising for application in determination and routine monitoring of these compounds in environmental water bodies.

Identification of opioids in surface and wastewaters by LC/QTOF-MS using retrospective data analysis

Opioids, both as prescription drugs and abuse substances, have been a hot topic and a focus of discussion in the media for the last few years. Although the literature published shows the occurrence of opioids and some of their metabolites in the aquatic environment, there are scarce data in the application of high resolution mass spectrometry (HRMS) for the analysis of these compounds in the environment. The use of HRMS allows increasing the number of opioids that can be studied as well as the detection of unknown opioids, their metabolites and potential transformation products. In this work, a retrospective analysis for the identification of opioids and their metabolites using a curated database was applied to surface water and wastewater samples taken in the state of Minnesota (U.S.) in 2009, which were previously analyzed by liquid chromatography/time-of-flight mass spectrometry (LC/TOF-MS) for antidepressants. The database comprised >200 opioids including natural opiates (e.g. morphine and codeine), their semi-synthetic derivatives (e.g. heroin, hydromorphone, hydrocodone, oxycodone, oxymorphone, meperidine and buprenorphine), fully synthetic opioids (e.g. fentanyl, methadone, tramadol, dextromethorphan and propoxyphene), as well as some of their metabolites (e.g. 6-monoacetylcodeine, dextrorphan, EDDP, normorphine and O-desmethyltramadol). Moreover, additional MS-MS experiments were performed to confirm their identification, as well as to recognize fragmentation patterns and diagnostic ions for several opioids. These data provide a better understanding of the historical occurrence of opioids and their metabolites in surface waters impacted by wastewater sources. The concentrations of individual opioids in surface water and wastewater effluent varied from 8.8 (EDDP) to 1640 (tramadol) ngL−1 and from 12 (dihydrocodeine) to 1288 (tramadol) ngL−1, respectively. The opioids with higher overall frequency detections were tramadol, dextromethorphan and its metabolite, dextrorphan.

Simultaneous quantification of commonly prescribed antiretroviral drugs and their selected metabolites in aqueous environmental samples by direct injection and solid phase extraction liquid chromatography - tandem mass spectrometry

The widespread implementation of antiretroviral therapy medication has made antiretroviral drugs (ARVDs) a significant pharmaceutical class in regions of high HIV infection rates. However, relatively little is known regarding the environmental occurrence of these emerging contaminants, and this is especially true for their metabolites. In this work, we report analytical methods to study the simultaneous occurrence of a range of common ARVDs and some of their known metabolites in surface water and wastewater. A novel direct injection liquid chromatography-tandem mass spectrometry (LC-MS/MS) method is reported for the analysis of ARVDs of different therapeutic classes and their selected metabolites in wastewater samples. In addition, a solid phase extraction (SPE) procedure was developed for pre-concentration of ARVs and metabolites from surface water samples. The respective methods proved suitable for the quantitative analysis of six parent ARVDs from three ARV classes, as well as three metabolites. Method validation showed average recoveries of 86% for the direct injection method, and 64% for the SPE method. With the exception of Zidovudine and the metabolites of Zidovudine and Ritonavir, all target ARVDs were detected in wastewater samples from two wastewater treatment plants in the Western Cape, South Africa. Higher concentrations were generally measured in influent compared to effluent samples, in the dry compared to the wet season as well as in chlorinated compared to uv-irradiated effluents. This study contributes for the first time quantitative data on the environmental occurrence of the known metabolites of Nevirapine (12-hydroxy-Nevirapine) and Efavirenz (8,14-dihydroxy-Efavirenz).

Occurrence of drugs of abuse in surface water from four Spanish river basins: Spatial and temporal variations and environmental risk assessment

The present work investigates the occurrence of 22 drugs of abuse (DAs) and metabolites in surface water from four Spanish River basins: Llobregat, Ebro, Jucar and Guadalquivir. To this end, samples were collected from 77 selected sites in two sampling campaigns conducted in 2010 and 2011. Analyses were performed by means of on-line solid phase extraction-liquid chromatography-electrospray-tandem mass spectrometry (on-line SPE-LC-ESI-MS/MS). Cocaine, its metabolite benzoylecgonine, ephedrine, MDMA (ecstasy), and methadone and its metabolite EDDP were the most ubiquitous compounds, being present in more than 50% of the samples. Overall, DAs were present at low ng/L levels, showing comparatively higher concentrations in small tributary rivers impacted by wastewater treatment plant effluents. The results obtained did not show a clear relationship between the concentrations of DAs and the hydrological conditions of the river basins. Differences in the occurrence of DAs between river basins were observed, but only for MDMA this finding could be confirmed in both sampling campaigns. These results overall suggest similar drugs consumption in the studied areas. Estimation of potential ecotoxicological effects using Hazard Quotient (HQ) ratios and a concentration addition model showed that in four samples the presence of DAs could represent certain risk to aquatic organisms.

Photochemical transformation of sunscreen agent benzophenone-3 and its metabolite in surface freshwater and seawater

The occurrence of sunscreen agents and their metabolites in surface waters gives rise to public concerns. However, little is known about the environmental fate of these pollutants at present, especially for their metabolites. In this study, we investigated the photochemical of sunscreen agents and their metabolites in natural waters, adopting benzophenone-3 (BP-3) and its human metabolite 4-hydroxybenzophenone (4-OH-BP3) as examples. Results show that only anionic forms of both BP-3 and 4-OH-BP3 can undergo direct photodegradation. The photolytic rates of both compounds in natural waters are faster as compared to those in pure water. Radical scavenging experiments revealed that triplet-excited dissolved organic matter (3DOM∗) was responsible for the indirect photodegradation of BP-3 and 4-OH-BP3 in seawater, whereas in freshwater, the indirect photodegradation of these two compounds was attributed to 3DOM∗ and ·OH. 1O2 plays a negligible role in their photodegradation because of the weak 1O2 reactivity. Furthermore, we probed the contribution of ·OH and 3DOM∗ to the photodegradation of both compounds in freshwater, and the results revealed that ·OH accounted for 56% and 59% of the observed photodegradation for BP-3 and 4-OH-BP3, respectively, whereas 3DOM∗ accounted for 43% and 12% of the observed photodegradation for BP-3 and 4-OH-BP3, respectively. These results are helpful in assessing the ecological risk of BP-3 and its metabolite in the aquatic environment.

Waterborne Risperidone Decreases Stress Response in Zebrafish.

The presence of drugs and their metabolites in surface waters and municipal effluents has been reported in several studies, but its impacts on aquatic organisms are not yet well understood. This study investigated the effects of acute exposure to the antipsychotic risperidone on the stress and behavioral responses in zebrafish. It became clear that intermediate concentration of risperidone inhibited the hypothalamic-pituitary-interrenal axis and displayed anxiolytic-like effects in zebrafish. The data presented here suggest that the presence of this antipsychotic in aquatic environments can alter neuroendocrine and behavior profiles in zebrafish.

Presence of Illicit Drugs in the Sarno River (Campania Region, Italy)

The presence of illicit drugs and their metabolites in surface waters has to be considered a new type of hazard, still unknown, for both the human health and the aquatic ecosystem, due to the potent pharmacological activities of all the illicit drugs. Our research was aimed at evaluating the presence of illicit drugs in the Sarno River (Campania region, Italy), crossing a densely populated area, the basin of the Sarno River, one of the largest and most important economic areas in Campania region, famous for the presence of zones with high landscape-environmental value. The drugs selected for this study were the most used in Campania region. The presence of illicit drugs in surface water was analyzed by a selective multi-residue assay based on liquid chromatographytandem mass spectrometry. The analysis showed the presence of all the illicit drugs investigated: cocaine and its main metabolites (benzoylecgonine, nor-benzoylecgonine), morphine, THC-COOH and codeine; cocaine was the most abundant illicit drug. The presence of illicit drugs and their metabolites in the Sarno River suggests new potential risk for the basin’s inhabitants, using water in the food chain, via field irrigation and animal feed, and for the health of the aquatic fauna.

In-situ calibration of POCIS for the sampling of polar pesticides and metabolites in surface water

Over the past years, passive sampling devices have been successfully used for the monitoring of various pollutants in water. The present work studied the uptake kinetics in surface water of ten polar pesticides and metabolites, using pharmaceutical POCIS samplers. The aim was to determine sampling rates from in-situ calibration and to compare results with those obtained earlier under laboratory conditions, with the final objective of assessing the impact of environmental conditions on POCIS field performance. Field results showed a low efficiency of POCIS uptake capacity for moderately polar compounds, such as propiconazole (logKow=3.72) and tebuconazole (logKow=3.7), that were present in the aqueous phase at very low levels. The in-situ sampling rates obtained in this study ranged from 169 to 479mLg−1day−1 and differ by a factor of 3–7.5 from Rs determined under laboratory conditions.

Widespread occurrence of neuro-active pharmaceuticals and metabolites in 24 Minnesota rivers and wastewaters

Concentrations of 17 neuro-active pharmaceuticals and their major metabolites (bupropion, hydroxy-bupropion, erythro-hydrobupropion, threo-hydrobupropion, carbamazepine, 10,11,-dihydro-10,11,-dihydroxycarbamazepine, 10-hydroxy-carbamazepine, citalopram, N-desmethyl-citalopram, fluoxetine, norfluoxetine, gabapentin, lamotrigine, 2-N-glucuronide-lamotrigine, oxcarbazepine, venlafaxine and O-desmethyl-venlafaxine), were measured in treated wastewater and receiving surface waters from 24 locations across Minnesota, USA. The analysis of upstream and downstream sampling sites indicated that the wastewater treatment plants were the major source of the neuro-active pharmaceuticals and associated metabolites in surface waters of Minnesota. Concentrations of parent compound and the associated metabolite varied substantially between treatment plants (concentrations±standard deviation of the parent compound relative to its major metabolite) as illustrated by the following examples; bupropion and hydrobupropion 700±1000ngL−1, 2100±1700ngL−1, carbamazepine and 10-hydroxy-carbamazepine 480±380ngL−1, 360±400ngL−1, venlafaxine and O-desmethyl-venlafaxine 1400±1300ngL−1, 1800±2300ngL−1. Metabolites of the neuro-active compounds were commonly found at higher or comparable concentrations to the parent compounds in wastewater effluent and the receiving surface water. Neuro-active pharmaceuticals and associated metabolites were detected only sporadically in samples upstream from the effluent outfall. Metabolite to parent ratios were used to evaluate transformation, and we determined that ratios in wastewater were much lower than those reported in urine, indicating that the metabolites are relatively more labile than the parent compounds in the treatment plants and in receiving waters. The widespread occurrence of neuro-active pharmaceuticals and metabolites in Minnesota effluents and surface waters indicate that this is likely a global environmental issue, and further understanding of the environmental fate and impacts of these compounds is warranted.

Direct Photolysis of Human Metabolites of the Antibiotic Sulfamethoxazole: Evidence for Abiotic Back-Transformation

The presence of potentially persistent and bioactive human metabolites in surface waters gives rise to concern; yet little is known to date about the environmental fate of these compounds. This work investigates the direct photolysis of human metabolites of the antibiotic sulfamethoxazole (SMX). In particular, we determined photolysis kinetics and products, as well as their concentrations in lake water. SMX, N-acetyl sulfamethoxazole, sulfamethoxazole β-D-glucuronide, 4-nitroso sulfamethoxazole, and 4-nitro sulfamethoxazole were irradiated under various light sources and pH conditions. All investigated metabolites, except sulfamethoxazole β-D-glucuronide were found to be more photostable than SMX under environmentally relevant conditions. Between two and nine confirmed photoproducts were identified for SMX-metabolites through ultraperformance liquid chromatography/high-resolution mass spectrometry. Interestingly, photolytic back-transformation to SMX was observed for 4-nitroso-SMX, indicating that this metabolite may serve as an environmental source of SMX. Moreover, two human metabolites along with SMX were regularly detected in Lake Geneva. The knowledge that some metabolites retain biological activity, combined with their presence in the environment and their potential to retransform to the parent compound, underlines the importance of including human metabolites when assessing the effects of pharmaceuticals in the environment.