Contamination profiles and mass loadings of macrolide antibiotics and illicit drugs from a small urban wastewater treatment plant

Mass loading and removal of select illicit drugs in two wastewater treatment plants in New York State and estimation of illicit drug usage in communities through wastewater analysis

Sewage epidemiology is a rapidly expanding field that can provide information on illicit drug usage in communities, based on the measured concentrations in samples from wastewater treatment plants (WWTPs). In this study, select illicit drugs (six drugs and eight metabolites) were determined on a daily basis for a week in wastewater, suspended particulate matter (SPM), and sludge from two WWTPs in the Albany area in New York State. The WWTP that served a larger population (∼100 000, with a flow rate of 83 300 m(3)/d) showed 3.2 (methadone) to 51 (3,4-methylenedioxyamphetamine; MDA) times higher mass flows of illicit drugs than did the WWTP that served a smaller population (∼15 000, with a flow rate of 6850 m(3)/d). The consumption rate of target illicit drugs in the communities served by the two WWTPs was estimated to range from 1.67 to 3510 mg/d/1000 people. Between the dissolved and particulate phases, the fraction of methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), amphetamine, and MDA sorbed to SPM ranged from 34.3% to 41.1% of the total mass in the waste stream. The removal efficiencies of illicit drugs from the two WWTPs ranged from 4% (norcocaine) to 99% (cocaine); however, methamphetamine, methadone, and EDDP showed a negative removal in WWTPs. The environmental emission of illicit drugs from WWTP discharges was calculated to range from 0.38 (MDEA) to 67.5 (EDDP) mg/d/1000 people. Other markers such as caffeine, paraxanthine, nicotine, and cotinine were found to predict the concentrations of select illicit drugs in raw wastewater (r(2) = 0.20-0.79; p ≤ 0.029).

Challenges of surveying wastewater drug loads of small populations and generalizable aspects on optimizing monitoring design

AIMS

Quantifying illicit drug loads through wastewater analysis (WWA) is an alternative approach to estimating population drug use. This study investigated the variability of daily drug loads in wastewater and their relationships to environmental factors over an extended period to: (i) explore the suitability of WWA in small populations and (ii) optimize the monitoring design for future studies.

DESIGN, SETTING, PARTICIPANTS

Daily wastewater samples (n = 1369 consecutive days) from a German village with approximately 7160 inhabitants.

MEASUREMENTS

Samples were analysed for cocaine and benzoylecgonine with liquid chromatography-tandem mass spectrometry. Time-series analysis was used to explore the effects of weather and other factors on daily cocaine loads. Subsampling was used to assess monitoring design.

FINDINGS

Cocaine loads [mean = 652 mgCOC /day, standard deviation (SD) = 498 mgCOC /day] increased over the study period, with higher values during winter and spring. Despite high day-to-day variation, loads were significantly higher during weekends [+161 mgCOC /day, 95% confidence interval (CI) = 115-207 mgCOC /day, P < 10(-4) ] and days with frost (+114 mgCOC /day, 95% CI = 6-223 mgCOC /day, P = 0.039) or snow (+150 mgCOC /day, 95% CI = 46-253 mgCOC /day, P = 0.005). Annual means estimated from 1-week periods were subject to approximately 60% relative error. Increasing sample size and changing sampling from consecutive days to stratified random decreased this uncertainty.

CONCLUSIONS

Day-to-day variation and seasonality of drug loads from the few long-term wastewater studies available to date suggest that up to 56 stratified random samples are required to obtain reliable (expected uncertainty around 10%) annual estimates of drug loads. Successfully assessing changes in consumption patterns or relationships to external factors requires larger sample sizes than estimating annual means, which holds true for high-prevalence drugs in small communities and low-prevalence drugs in big cities.

Reduction of clarithromycin and sulfamethoxazole-resistant Enterococcus by pilot-scale solar-driven Fenton oxidation

The presence of pathogenic antibiotic-resistant bacteria in aquatic environments has become a health threat in the last few years. Their presence has increased due to the presence of antibiotics in wastewater effluents, which are not efficiently removed by conventional wastewater treatments. As a result there is a need to study the possible ways of removal of the mixtures of antibiotics present in wastewater effluents and the antibiotic-resistant bacteria, which may also spread the antibiotic resistance genes to other bacterial populations. In this study the degradation of a mixture of antibiotics i.e. sulfamethoxazole and clarithromycin, the disinfection of total enterococci and the removal of those resistant to: a) sulfamethoxazole, b) clarithromycin and c) to both antibiotics have been examined, along with the toxicity of the whole effluent mixture after treatment to the luminescent aquatic bacterium Vibrio fischeri. Solar Fenton treatment (natural solar driven oxidation) using Fenton reagent doses of 50 mg L(-1) of hydrogen peroxide and 5 mg L(-1) of Fe(3+) in a pilot-scale compound parabolic collector plant was used to examine the disinfection and antibiotic resistance removal efficiency in different aqueous matrices, namely distilled water, simulated and real wastewater effluents. There was a faster complete removal of enterococci and of antibiotics in all aqueous matrices by applying solar Fenton when compared to photolytic treatment of the matrices. Sulfamethoxazole was more efficiently degraded than clarithromycin in all three aqueous matrices (95% removal of sulfamethoxazole and 70% removal of clarithromycin in real wastewater). The antibiotic resistance of enterococci towards both antibiotics exhibited a 5-log reduction with solar Fenton in real wastewater effluent. Also after solar Fenton treatment, there were 10 times more antibiotic-resistant enterococci in the presence of sulfamethoxazole than in the presence of clarithromycin. Finally, the toxicity of the treated wastewater to V. fischeri remained very low throughout the treatment time.

Occurrence of drugs of abuse and benzodiazepines in river waters from the Madrid Region (Central Spain)

This work investigates, for the first time, the occurrence of 10 drugs of abuse, six metabolites, and three benzodiazepines in surface waters from the Jarama and Manzanares Rivers in the Madrid Region, the most densely populated area in Spain and one of the most densely populated in Europe. The results of this study have shown the presence of 14 out of the 19 compounds analyzed at concentrations ranging from 1.45 to 1020 ng L(-1). The most ubiquitous compounds, found in 100% of the samples, were the cocaine metabolite benzoylecgonine (BE), the amphetamine-like compound ephedrine (EPH), the opioids morphine (MOR), methadone (METH), and the METH metabolite 2-ethylene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), and the three investigated benzodiazepines alprazolam (ALP), diazepam (DIA) and lorazepam (LOR). Meanwhile, the largest concentrations observed corresponded to EPH (up to 1020 ng L(-1)), BE (823 ng L(-1)), EDDP (151 ng L(-1)), and LOR (167 ng L(-1)). The only not detected compounds were heroin (HER) and its metabolite 6-acetylmorphine (6ACM), lysergic acid diethylamide (LSD) and its metabolite 2-oxo-3-hydroxy-LSD (OH-LSD), and Δ(9)-tetrahydrocannabinol (THC). Overall, the levels measured are comparatively higher than those previously reported in Europe. Comparison of the results obtained for samples collected on different days (Thursday and Sunday) did not show meaningful differences between weekdays and weekends. The lack of (eco)toxicological data does not permit to predict or disregard potential adverse effects on wildlife. Risk assessment in humans would require further knowledge, not currently available, on exposure to these compounds through other routes like drinking water and/or food.

Occurrences and fate of selected human antibiotics in influents and effluents of sewage treatment plant and effluent-receiving river Yamuna in Delhi (India)

Antibiotics consumption has increased worldwide, and their residues are frequently reported in aquatic environments. It is believed that antibiotics reach aquatic water bodies through sewage. Medicine consumed for healthcare practices are often released into sewage, and after sewage treatment plant, it reaches the receiving water bodies of lakes or rivers. In the present study, we determined the fate of some commonly used antibiotics in a sewage treatment plant (STP) located in Delhi and the environmental concentration of these antibiotics in the Yamuna River, which receives the sewage and industrial effluent of Delhi. There are many reports on antibiotics occurrences in STP and river water worldwide, but monitoring data from the Indian subcontinent is sparse. Samples were taken from a STP and from six sampling sites on the Yamuna River. Several antibiotics were tested for using offline solid-phase extraction followed by high-performance liquid chromatography equipped with photodiode array analysis. Recoveries varied from 25.5-108.8 %. Ampicillin had the maximum concentration in wastewater influents (104.2 ± 98.11 μg l(-1)) and effluents (12.68 ± 8.38 μg l(-1)). The fluoroquinolones and cephalosporins had the lower concentrations. Treatment efficiencies varied between 55 and 99 %. Significant amounts of antibiotics were discharged in effluents and were detected in the receiving water body. The concentration of antibiotics in the Yamuna River varied from not detected to 13.75 μg l(-1) (ampicillin) for the compounds investigated.

Illicit drugs and the environment--a review

Illicit drugs and their metabolites are the latest group of emerging pollutants. Determination of their concentration in environment (such as water bodies, soil, sediment, air) is an indirect tool to estimate the community level consumption of illicit drug and to evaluate potential ecotoxicological impacts from chronic low level exposure. They enter the wastewater network as unaltered drugs and/or their active metabolites by human excretion after illegal consumption or by accidental or deliberate disposal from clandestine drug laboratories. This article critically reviews the occurrence and concentration levels of illicit drugs and their metabolites in different environmental compartments (e.g., wastewater, surface waters, groundwater, drinking water, and ambient air) and their potential impact on the ecosystem. There is limited published information available on the presence of illicit drugs in the environment, reports are available mainly from European countries, UK, USA, and Canada but there is a lack of information from the remainder of the world. Although the environmental concentrations are not very high, they can potentially impact the human health and ecosystem functioning. Cocaine, morphine, amphetamine, and MDMA have potent pharmacological activities and their presence as complex mixtures in water may cause adverse effect on aquatic organisms and human health. However, there is no current regulation demanding the determination of occurrence of these emerging pollutants in treated wastewater, surface water, drinking water, or atmosphere. Thus, critical investigation on distribution pattern of this new group of emerging contaminant and their potential harmful impact on our environment needs immediate attention.

Licit and illicit drugs in a wastewater treatment plant in Verona, Italy

The occurrence of 12 active substances among licit and illicit drugs was investigated over a 2 week period inflowing and outflowing in an activated sludge wastewater treatment plant in the city of Verona, Northern Italy. Chemical analyses were performed by means of on-line solid phase extraction coupled to high performance liquid chromatography-tandem mass spectrometry in order to minimize sample pre-treatment. Quantifiable concentrations, up to hundreds of ng/L, were detected in influent and in effluent only for carbamazepine, codeine and benzoylecgonine. Such values are in accordance with literature data, so as removal efficiencies: it was observed that there was pretty much no abatement for carbamazepine, while average removal percentages of about 60% and 90% were calculated for codeine and benzoylecgonine, respectively. These results provide useful information (also concerning some active principles never or rarely detected, up to now, such as lormetazepam) for integrated water cycle managing, also taking into account the specific characteristics of the receiving water basin.

Presence of illicit drugs and metabolites in influents and effluents of 25 sewage water treatment plants and map of drug consumption in France

Consumption of illicit drugs is a new concern for water management that must be considered not only because of the social and public health aspects but also in an environmental context in relation with the contamination of surface waters. Indeed, sewage treatment plant (STP) effluents contain drug residues that have not been eliminated since STP treatments are not completely efficient in their removal. We developed and validated an HPLC-MS/MS analytical method to assess the concentrations of 17 illicit drugs and metabolites in raw urban wastewaters: cocaine and its metabolites, amphetamine and amphetamine-likes (methamphetamine, MDMA, MDEA, MDA), opiates and opiate substitutes (methadone and buprenorphine), and THC-COOH cannabis metabolite. This method has been applied to the analysis of influent and effluent samples from 25 STPs located in France all over the country. The results allowed evaluating the drug consumption in the areas connected to the STPs and the efficiency of the treatment technology implied. We selected STPs according to their volume capacity, their treatment technologies (biofilters, activated sludges, MBR) and their geographical location. In influents, the concentrations varied between 6 ng/L for EDDP (main metabolite of methadone) and 3050 ng/L for benzoylecgonine (cocaine metabolite). Consumption maps were drawn for cocaine, MDMA, opiates, cannabis and amphetamine-like compounds. Geographical significant differences were observed and highlighted the fact that drug consumption inside a country is not homogeneous. In parallel, comparisons between STP technology processes showed differences of efficiency. More, some compounds appear very resistant to STP processes leading to the contamination of receiving water.

Determination of some frequently used antibiotics in waste waters using solid phase extraction followed by high performance liquid chromatography with diode array and mass spectrometry detection

This study is focused on the determination of some important antibiotics from different classes in waste water samples using solid phase extraction followed by high performance liquid chromatography with two detectors, diode array and mass spectrometer in positive ionisation mode. The investigated antibiotics include three penicillins (amoxicillin, ampicillin, penicillin G), two cephalosporins (ceftazidime, ceftriaxone), and two tetracyclines (tetracycline, doxycycline). The studied antibiotics were extracted from waste water samples using hydrophilic-lipophilic balanced cartridges. The extraction of antibiotics from water matrices was tested at several pH values. The best recoveries were obtained at pH 3 and 7 respectively. Depending on the nature of antibiotic, the limits of detection and quantification were obtained in the range of 0.07–0.92 µg mL−1 and 0.21–2.77 µg mL−1 respectively. Influent and effluent waste water samples were collected from a Waste Water Treatment Plant from Romania in order to detect the studied antibiotics. The antibiotics detected in the influent waste water samples were ceftriaxone (334 µg L−1), tetracycline (146 µg L−1) and doxycycline (110 µg L−1). In effluent waste water samples no target antibiotics were detected.

Antibiotic contamination in a typical developing city in south China: occurrence and ecological risks in the Yongjiang River impacted by tributary discharge and anthropogenic activities

The occurrence and distribution of ten selected antibiotics from three groups (sulfonamides, macrolides, and trimethoprim) were investigated in the Yongjiang River, which flows through Nanning City, a typical developing city in China. The study also assessed the ecological risks and the potential effects caused by discharge from tributaries and anthropogenic activities. Concentrations of most of the antibiotics were elevated along the section of the river in the urban area, highlighting the significant impact of high population density and human activities on the presence of antibiotics in the environment. The concentrations in the tributaries (ranged from not detected to 1336ngL(-1)) were generally higher than those in the main stream (ranged from not detected to 78.8ngL(-1)), but both areas contained the same predominant antibiotics, revealing the importance of tributary discharge as a source of antibiotic pollution. A risk assessment for the surface water contamination revealed that sulfamethoxazole and erythromycin posed high ecological risks to the most sensitive aquatic organisms (Synechococcus leopoliensis and Pseudokirchneriella subcapitata, respectively) in the midstream and some tributaries. Most of the selected antibiotics presented high ecological risks (risk quotients up to 95) in the sediments.

Urban wastewater treatment plants as hotspots for the release of antibiotics in the environment: a review

Urban wastewater treatment plants (UWTPs) are among the main sources of antibiotics' release into various compartments of the environment worldwide. The aim of the present paper is to critically review the fate and removal of various antibiotics in wastewater treatment, focusing on different processes (i.e. biological processes, advanced treatment technologies and disinfection) in view of the current concerns related to the induction of toxic effects in aquatic and terrestrial organisms, and the occurrence of antibiotics that may promote the selection of antibiotic resistance genes and bacteria, as reported in the literature. Where available, estimations of the removal of antibiotics are provided along with the main treatment steps. The removal efficiency during wastewater treatment processes varies and is mainly dependent on a combination of antibiotics' physicochemical properties and the operating conditions of the treatment systems. As a result, the application of alternative techniques including membrane processes, activated carbon adsorption, advanced oxidation processes (AOPs), and combinations of them, which may lead to higher removals, may be necessary before the final disposal of the effluents or their reuse for irrigation or groundwater recharge.

Combination of upflow anaerobic sludge blanket (UASB) and membrane bioreactor (MBR) for berberine reduction from wastewater and the effects of berberine on bacterial community dynamics

Berberine is a broad-spectrum antibiotic extensively used in personal medication. The production of berberine results in the generation of wastewater containing concentrated residual berberine. However, few related studies up to date focus on berberine removal from wastewaters. In this study, a lab-scale upflow anaerobic sludge blanket (UASB)-membrane bioreactor (MBR) process was developed for berberine removal from synthetic wastewater. The performance of the UASB-MBR system on berberine, COD and NH(4)(+)--N removal was investigated at different berberine loadings. And the effects of berberine on bacterial communities were evaluated using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Results showed that, as the increase of berberine loadings, UASB performance was affected remarkably, whereas, efficient and stable performance of MBR ensured the overall removal rates of berberine, COD and NH(4)(+)--N consistently reached up to 99%, 98% and 98%, respectively. Significant shifts of bacterial community structures were detected in both UASB and MBR, especially in the initial operations. Along with the increase of berberine loadings, high antibiotic resisting species and some functional species, i.e. Acinetobacter sp., Clostridium sp., Propionibacterium sp., and Sphingomonas sp. in UASB, as well as Sphingomonas sp., Methylocystis sp., Hydrogenophaga sp. and Flavobacterium sp. in MBR were enriched in succession.

A comprehensive chromatographic comparison of amphetamine and methylamphetamine extracted from river water using molecular imprinted polymers and without the need for sample derivatization

This work explores the differences between two GCMS instruments for the determination of amphetamine and methylamphetamine extracted from water samples (ultra pure water and river water) without the necessity for derivatization. The instruments contained different generations of gas chromatograph and mass selective detector components and revealed significantly different results when presented with the same samples. The extraction methodology also compared two SPE systems. The extraction efficiency of commercially available molecular imprinted polymers as a sorbent in SPE was compared with commonly used hydrophilic balance sorbent. Molecular imprinted polymers provided excellent recoveries (81 ± 2% and 108 ± 3% at 30 μg L(-1), and 94 ± 2% and 94 ± 2% at 200 μg L(-1) for amphetamine and methylamphetamine, respectively). The best LOD obtained was sufficient for the determination of both drugs extracted from river water (0.029 ± 0.003 and 0.015 ± 0.004 μg L(-1) for amphetamine and methylamphetamine, respectively). These were comparable to literature values obtained through conventional extraction and analysis using LC-MS/MS but had the advantage of being achieved using an underivatized GCMS method.

Investigation of drugs of abuse and relevant metabolites in Dutch sewage water by liquid chromatography coupled to high resolution mass spectrometry

An extensive study on the presence of illicit drugs and pharmaceuticals with potential for abuse in sewage waters was made for the first time in the Netherlands. A total number of 24 target drugs were investigated in influent and effluent wastewater using liquid chromatography coupled to a high resolution Orbitrap mass spectrometer. This powerful analyzer has allowed not only the detection and identification of the compounds under investigation, but also their quantification at very low levels, which is highly innovative in the field of drugs of abuse. Samples were taken from five sewage treatment plants (STPs) during a whole week. The selected STPs served four cities of different size and an international airport. Daily variances of drug loads were demonstrated and removal efficiencies calculated for each drug and STP individually. Twelve target compounds were found in at least one influent or effluent, and highest concentrations were observed in influents collected from more urbanized areas. The compounds more frequently detected were amphetamine, benzoylecgonine, cocaine and THCCOOH together with the pharmaceuticals codeine, oxazepam and temazepam. Established week trends in consumption of drugs showed distinct differences between individual drugs. A slightly different occurrence pattern was observed in wastewaters from the airport. Thus, methamphetamine was only detected at Schiphol, a fact that was interpreted to be caused by consumption of this drug by travelers. Despite the fact that the Netherlands has frequently been criticized for its liberal drug policy the results from this study did not reveal higher drug consumption than found elsewhere, with the exception of cannabis.

Occurrence of ciprofloxacin, enrofloxacin, and florfenicol in animal wastewater and water resources

Antimicrobial agent residues are becoming an intractable environmental problem in soil, surface, and underground water. To obtain a broad profile of residues in animal wastewater and surface water, 24 animal wastewater, 8 animal farm effluent, 18 river water, and 8 pond water samples taken in Jiangsu in eastern China were monitored for enrofloxacin, ciprofloxacin, and florfenicol using solid phase extraction and high performance liquid chromatography/electrospray ionization-tandem mass spectrometry (HPLC/ESI-MS/MS) techniques. The results revealed that two antibacterials were detected simultaneously in 49.1% of samples, followed by three antibacterials (22.6%) and one antibacterial (22.6%). Up to 3.35, 5.93, and 2.10 μg L for ciprofloxacin, 1.09, 4.24, and 0.50 μg L for enrofloxacin, and 0.95, 2.40, and 2.84 μg L for florfenicol were detected in animal farm-effluent, river, and pond water, respectively. The maximum concentrations of ciprofloxacin and enrofloxacin in animal wastewaters were 7.49 and 8.77 μg L, respectively. Furthermore, residue levels of ciprofloxacin and florfenicol showed at least two statistical differences between any two sampling areas or two animal farms. Enrofloxacin showed no statistical difference among the sampling areas and the animal farms.

Normalized diurnal and between-day trends in illicit and legal drug loads that account for changes in population

Drug concentrations in composite municipal wastewater samples and census-based estimates of population are used to derive daily loads of illicit substances that are indexed to population. However, such estimates do not provide information on the diurnal trends of substance excretion nor can they account for changes in population. To address these limitations, a series of 1 h composites created by sampling wastewater influent at 6 min intervals was collected over four consecutive days at a single wastewater treatment plant. Creatinine (a urinary indicator), caffeine, methamphetamine, benzoylecgonine (BZE), and cocaine were analyzed by liquid chromatography/tandem mass spectrometry (LC-MS/MS). Diurnal trends and between-day trends were substance specific and related to the number of estimated doses and excretory half-life. Normalization to creatinine yielded trends in substances that differed significantly from non-normalized trends by accounting for changes in population within the municipality studied. Increases in normalized substance excretion observed during early morning hours originate from individuals among the resident population of the municipality due to the absence of commuters.

Point sources of emerging contaminants along the Colorado River Basin: source water for the arid Southwestern United States

Emerging contaminants (ECs) (e.g., pharmaceuticals, illicit drugs, personal care products) have been detected in waters across the United States. The objective of this study was to evaluate point sources of ECs along the Colorado River, from the headwaters in Colorado to the Gulf of California. At selected locations in the Colorado River Basin (sites in Colorado, Utah, Nevada, Arizona, and California), waste stream tributaries and receiving surface waters were sampled using either grab sampling or polar organic chemical integrative samplers (POCIS). The grab samples were extracted using solid-phase cartridge extraction (SPE), and the POCIS sorbents were transferred into empty SPEs and eluted with methanol. All extracts were prepared for, and analyzed by, liquid chromatography-electrospray-ion trap mass spectrometry (LC-ESI-ITMS). Log D(OW) values were calculated for all ECs in the study and compared to the empirical data collected. POCIS extracts were screened for the presence of estrogenic chemicals using the yeast estrogen screen (YES) assay. Extracts from the 2008 POCIS deployment in the Las Vegas Wash showed the second highest estrogenicity response. In the grab samples, azithromycin (an antibiotic) was detected in all but one urban waste stream, with concentrations ranging from 30ng/L to 2800ng/L. Concentration levels of azithromycin, methamphetamine and pseudoephedrine showed temporal variation from the Tucson WWTP. Those ECs that were detected in the main surface water channels (those that are diverted for urban use and irrigation along the Colorado River) were in the region of the limit-of-detection (e.g., 10ng/L), but most were below detection limits.

Occurrence and distribution of selected pharmaceuticals and personal care products in aquatic environments: a comparative study of regions in China with different urbanization levels

PURPOSE

We analyzed and compared the distributions of 13 target pharmaceuticals in different water samples from the Hangzhou metropolitan area and Linan County, Southeast China.

METHODS

Sampling was conducted in five hospitals, two wastewater treatment plants (WWTPs), and Qiantang River. Samples were concentrated by solid-phase extraction and PPCP concentrations were determined by UPLC-MS/MS.

RESULTS AND DISCUSSION

Trimethoprim, erythromycin A dihydrate, norfloxacin, ofloxacin, diclofenac sodium, and atenolol were the most frequently detected pharmaceuticals in hospital effluents. Most of the pharmaceutical concentrations in hospital effluents were higher than those in the WWTP influents. Although both WWTPs adopt the anaerobic-aerobic-anoxic treatment process, the removal rates for pharmaceuticals, such as trimethoprim and diclofenac sodium, were completely different. Meanwhile, erythromycin A dihydrate, ofloxacin, penicillin-G, cephalexin, cefazolin, ibuprofen, and diclofenac sodium were detected in Qiantang River.

CONCLUSIONS

These results indicate that hospitals are more concentrated sources of pharmaceuticals than WWTPs, and the WWTPs are not the only route of entry of pharmaceuticals into aquatic environments in these two regions.

Adsorption of the antiepileptic carbamazepine onto agricultural soils

Carbamazepine is an antiepileptic pharmaceutical which is commonly found in environmental matrices. It passes through wastewater treatment plants (WWTPs) almost completely unaffected and has been found to be highly persistent in the environment. The application of sludge in agricultural fields and the use of WWTP effluents for irrigation constitute a potential source of soil contamination. Consequently, the assessment of the interaction between carbamazepine and soils is of crucial importance to understand its fate in the environment. To monitor the sorption behavior of carbamazepine onto agricultural soils, batch equilibrium experiments were performed using soils subjected to distinct long-term fertilizations. In order to follow the adsorption experiments, an UV spectral deconvolution methodology was applied and the results compared with those from micellar electrokinetic chromatography. The results obtained by both methods did not present significant statistical differences at 95% confidence level. Therefore, it was proven that, in the context of adsorption studies, UV spectral deconvolution is a valid alternative to common chromatographic methods, with the major advantage of being a simple and fast procedure. The adsorption of carbamazepine onto the selected soils was satisfactorily described by the Freundlich model. The obtained Freundlich parameters (K(F)) (between 1.79 ± 0.07 and 4.8 ± 0.2 mg kg(-1) (mg L(-1))(-N)) indicate that the adsorption behavior of carbamazepine is dependent on the soil fertilization. Also, it is not extensively sorbed, indicating that carbamazepine present in soils can be a potential source of contamination of surface and ground waters through run-off and infiltration.

Occurrence of antibiotics in eight sewage treatment plants in Beijing, China

The occurrence, removal efficiency and seasonal variation of 22 antibiotics, including eight fluoroquinolones, nine sulfonamides and five macrolides, were investigated in eight sewage treatment plants (STPs) in Beijing, China. A total of 14 antibiotics were detected in wastewater samples, with the maximum concentration being 3.1 μg L(-1) in the influent samples and 1.2 μg L(-1) in the effluent samples. The most frequently detected antibiotics were ofloxacin, norfloxacin, sulfadiazine, sulfamethoxazole, erythromycin and roxithromycin; of these, the concentration of ofloxacin was the highest in most of the influent and effluent samples. Eighteen antibiotics were detected in the sludge samples, with concentrations ranging from 1.0×10(-1) to 2.1×10(4) μg kg(-1). The dominant antibiotics found in the sludge samples were the fluoroquinolones, with ofloxacin having the highest concentration in all the sludge samples. The antibiotics could not be removed completely by the STPs, and the mean removal efficiency ranged from -34 to 72%. Of all the antibiotics, the fluoroquinolones were removed comparatively more efficiently, probably due to their adsorption to sludge. Seasonal variation of the antibiotics in the sludge samples was also studied. The concentrations of antibiotics in winter were higher than in spring and autumn. Since the total levels of the fluoroquinolones detected in the influent samples were lower than the predicted no-effect concentration (PNEC) of 8.0 μg L(-1), the residues of these antibiotics would be unlikely to have adverse effects on microorganisms involved in sewage treatment processes.

Interpreting methamphetamine levels in a high-use community

INTRODUCTION

Illicit drug use is a largely hidden phenomenon, and population measures are notoriously problematic. Reliable and valid data for local, regional, and national public health and other interventions are needed.

METHODS

To address this information, we examined temporal trends within and across weeks in methamphetamine (MA) in a single location in order to inform a sampling plan for understanding long-term trends in MA use based on sampling raw influent to wastewater treatment plants. The measured concentrations in the wastewater are used to estimate the total mass of MA consumed rather than the number of doses due to the uncertainty surrounding methamphetamine purity, mass of MA per dose, and the number of doses used per day.

RESULTS

Results from a region with high levels of MA use indicate that MA levels do not differ significantly between weekdays and weekends (p = 0.1), consistent with a predominately regular, daily use pattern use. The potential contribution of legal sales of D: - and L: -MA to the mass of MA consumed within the community was estimated to range from 3-8%. Limitations and uncertainties associated with estimating the mass of MA consumption include small contributions of prescription and over-the-counter drugs that are metabolized to MA as well as measurement and sampling variability.

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.

Antibiotics pollution in Jiulong River estuary: source, distribution and bacterial resistance

To gain insight into the antibiotic pollution in the Jiulong River estuary and the pollutant sources, we analyzed the concentration of 22 widely-used antibiotics in water samples collected from the river and estuary, 17 and 18 sampling sites, respectively. Contamination with sulfonamides, quinolones and chloramphenicols was frequently detected and the distribution pattern of antibiotics suggested that most of the pollutants are from the Jiulong River, especially from the downstream watersheds. To reveal the ecological effects, we isolated 35 bacterial strains from the estuary and analyzed their antibiotic resistance to the eight most frequently detected antibiotics. The bacteria were subsequently classified into seven different genera by 16SrDNA sequencing. Up to 97.1% of the bacteria showed resistance and 70.6% of strains showed multi-resistance to these antibiotics, especially to sulfonamides. This study demonstrated a pattern of antibiotic contamination in the Jiulong River and its estuary and illustrated high bacterial antibiotic resistance which was significantly correlated with the average antibiotics concentrations and detected frequencies in the estuary.

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.

Phosphorus recovery from fosfomycin pharmaceutical wastewater by wet air oxidation and phosphate crystallization

Fosfomycin pharmaceutical wastewater contains highly concentrated and refractory antibiotic organic phosphorus (OP) compounds. Wet air oxidation (WAO)-phosphate crystallization process was developed and applied to fosfomycin pharmaceutical wastewater pretreatment and phosphorus recovery. Firstly, WAO was used to transform concentrated and refractory OP substances into inorganic phosphate (IP). At 200°C, 1.0MPa and pH 11.2, 99% total OP (TOP) was transformed into IP and 58% COD was reduced. Subsequently, the WAO effluent was subjected to phosphate crystallization process for phosphorus recovery. At Ca/P molar ratio 2.0:1.0 or Mg/N/P molar ratio 1.1:1.0:1.0, 99.9% phosphate removal and recovery were obtained and the recovered products were proven to be hydroxyapatite and struvite, respectively. After WAO-phosphate crystallization, the BOD/COD ratio of the wastewater increased from 0 to more than 0.5, which was suitable for biological treatment. The WAO-phosphate crystallization process was proven to be an effective method for phosphorus recovery and for fosfomycin pharmaceutical wastewater pretreatment.

Degradation of chelating agents in aqueous solution using advanced oxidation process (AOP)

This article presents an overview with critical analysis of technical applicability of advanced oxidation process (AOP) in removing chelating agents from aqueous solution. Apart from the effect of metals for chelating agents as a major influencing factor, selected information such as pH, oxidant's dose, concentrations of pollutants and treatment performance is presented. The performance of individual AOP is compared. It is evident from our literature survey that photocatalysis with UV irradiation alone or coupled with TiO(2), ozonation and Fenton's oxidation are frequently applied to mineralize target pollutants. Overall, the selection of the most suitable AOP depends on the characteristics of effluents, technical applicability, discharge standard, regulatory requirements and environmental impacts.

Sorption and biodegradation of sulfonamide antibiotics by activated sludge: experimental assessment using batch data obtained under aerobic conditions

This study investigated the adsorption, desorption, and biodegradation characteristics of sulfonamide antibiotics in the presence of activated sludge with and without being subjected to NaN(3) biocide. Batch experiments were conducted and the relative contributions of adsorption and biodegradation to the observed removal of sulfonamide antibiotics were determined. Three sulfonamide antibiotics including sulfamethoxazole (SMX), sulfadimethoxine (SDM), and sulfamonomethoxine (SMM), which had been detected in the influent and the activated sludge of wastewater treatment plants (WWTP) in Taiwan, were selected for this study. Experimental results showed that the antibiotic compounds were removed via sorption and biodegradation by the activated sludge, though biodegradation was inhibited in the first 12 h possibly due to competitive inhibition of xenobiotic oxidation by readily biodegradable substances. The affinity of sulfonamides to sterilized sludge was in the order of SDM > SMM > SMX. The sulfonamides existed predominantly as anions at the study pH of 6.8, which resulted in a low level of adsorption to the activated sludge. The adsorption/desorption isotherms were of a linear form, as well described by the Freundlich isotherm with the n value approximating unity. The linear distribution coefficients (K(d)) were determined from batch equilibrium experiments with values of 28.6 ± 1.9, 55.7 ± 2.2, and 110.0 ± 4.6 mL/g for SMX, SMM, and SDM, respectively. SMX, SMM, and SDM desorb reversibly from the activated sludge leaving behind on the solids 0.9%, 1.6%, and 5.2% of the original sorption dose of 100 μg/L. The sorbed antibiotics can be introduced into the environment if no further treatments were employed to remove them from the biomass.

Photodegradation of azithromycin in various aqueous systems under simulated and natural solar radiation: kinetics and identification of photoproducts

This article describes the photolysis of azithromycin, a macrolide antibiotic with reported occurrence in environmental waters, under simulated solar radiation. The photodegradation followed first-order reaction kinetics in five matrices examined. In HPLC water, the degradation rate was the slowest (half-life: 20h), whereas in artificial freshwater supplemented with nitrate (5mgL(-1)) or humic acids (0.5mgL(-1)) the degradation of azithromycin was enhanced by factors of 5 and 16, respectively, which indicated the role of indirect photolysis involving the formation of highly reactive species. Following chromatographic separation on a UPLC system, the characterization of the transformation products was accomplished using high-resolution QqToF-MS analysis. The presence of seven photoproducts was observed and their formation was postulated to originate from (bis)-N-demethylation in the desosamine sugar, O-demethylation in the cladinose sugar, combinations thereof, as well as from hydrolytic cleavages of the desosamine and/or cladinose residue. Two of these photoproducts could also be detected in natural photodegradation process in river water which was spiked with azithromycin.

Occurrence of veterinary antibiotics in animal wastewater and surface water around farms in Jiangsu Province, China

The objective of this investigation was to obtain a broad profile of veterinary antibiotics residues in animal wastewater and surface water around large-scale livestock and poultry farms in Jiangsu Province of China. Therefore, 53 samples collected from 27 large-scale animal farms in 11 cities and counties of Jiangsu Province in 2009, were monitored for 10 selected veterinary antibiotics using solid phase extraction and high performance liquid chromatography/electrospray ionization-tandem mass spectrometry (HPLC/ESI-MS/MS) techniques. Ten veterinary antibiotics were found in animal wastewaters, eight antibiotics were detected in pond waters, and animal farm-effluents and river water samples were contaminated by nine antibiotics. The most frequently detected antibiotics were sulfamethazine (75%), oxytetracycline (64%), tetracycline (60%), sulfadiazine (55%) and sulfamethoxazole (51%) which were detected with a maximum concentration of 211, 72.9, 10.3, 17.0 and 63.6 μg L(-1), respectively. The maximum concentration of 0.55 μg L(-1) for cyromazine, 3.67 μg L(-1) for chlortetracycline, 0.63 μg L(-1) for sulfadoxine, 39.5 μg L(-1) for doxycycline and 0.64 μg L(-1) for sulfaquinoxaline were determined in the collected samples. In general, the maximum concentration of the selected veterinary antibiotics was detected in animal wastewaters except for chlortetracycline in animal farm-effluents. In addition, residue levels of selected veterinary antibiotics in animal wastewater and surface water around the farms were related to animal species and have a high spatial variation.

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.

Method development and application to determine potential plant uptake of antibiotics and other drugs in irrigated crop production systems

Studies have shown the detection of emerging contaminants (ECs), of which pharmaceuticals are a subset, in surface waters across the United States. The objective of this study was to develop methods, and apply them, to evaluate the potential for food chain transfer when EC-containing waters are used for crop irrigation. Greenhouse experiments were performed in which select food crops were irrigated with water spiked with three antibiotics. Field experiments, at two different sites, were conducted. Select crops were irrigated with wastewater effluent known to contain ECs, EC-free well water, and Colorado River water containing trace-level ECs. The results of the greenhouse studies show the potential for uptake of one or more of the antibiotics evaluated, albeit at very low levels. In those food crops watered with wastewater effluent, only an industrial flavoring agent, N,N'-dimethylphenethylamine (DMPEA), was consistently found. None of the evaluated contaminants were found in crops irrigated with Colorado River water.

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).

Impact of wastewaters and hospital effluents on the occurrence of controlled substances in surface waters

We have investigated the occurrence of controlled drugs in two rivers, two wastewater treatment plants (WWTPs) and five hospital effluents in Taipei, Taiwan, and report here the concentrations of controlled drugs used as prescription medication or drugs of abuse. Of the target drugs, morphine, codeine, methamphetamines and ketamine were observed in significant quantities in hospital effluents, with maximum concentrations of 1240, 378, 260 and 206 ng L(-1), respectively. The other six compounds (including metabolites) were found at trace levels or below the method detection limits. In addition, the high occurrence in river waters of methamphetamine, codeine and ketamine (maximum values 405, 57, and 341 ng L(-1), respectively) indicated the significant prevalence of these controlled drugs. This study demonstrated that effluents from hospitals and clinics and treated WWTP effluents contribute to the controlled substances that eventually reach natural rivers. We hypothesize that the occurrence of controlled drugs in the environment can be attributed to two main sources: (1) substance abuse by individuals and (2) treatment with prescription medication for acute and chronic pain. The presence of these contaminants in the aquatic environment may pose significant risk to aquatic and human life. Further studies are needed for verification and may contribute to the development of sustainable strategies for environmental remediation.

Illicit drugs in Canadian municipal wastewater and estimates of community drug use

In this study of wastewater treatment plants in three Canadian cities, selected illicit drugs, including cocaine and its major metabolite, benzoylecgonine (BE), amphetamine, methamphetamine and ecstasy (i.e. MDMA) were detected in untreated wastewater. Cocaine was the most widely used illicit drug at a median level for the 3 cities of 15.7 doses per day per 1000 people. For the other drugs, the median doses per day per 1000 people were 1.8 for amphetamine, 4.5 for methamphetamine and 0.4 for ecstasy. Methamphetamine use was highest in the largest city and cocaine use was lowest in the smallest city. Removal of the illicit drugs by wastewater treatment was generally >50%, except in a WWTP that uses primary treatment. The community consumption estimate for ecstasy in the present study is far below published estimates of the prevalence of ecstasy use among the Canadian population, which may be due to only occasional use of ecstasy.

Pharmacologically active compounds in the environment and their chirality

Pharmacologically active compounds including both legally used pharmaceuticals and illicit drugs are potent environmental contaminants. Extensive research has been undertaken over the recent years to understand their environmental fate and toxicity. The one very important phenomenon that has been overlooked by environmental researchers studying the fate of pharmacologically active compounds in the environment is their chirality. Chiral drugs can exist in the form of enantiomers, which have similar physicochemical properties but differ in their biological properties such as distribution, metabolism and excretion, as these processes (due to stereospecific interactions of enantiomers with biological systems) usually favour one enantiomer over the other. Additionally, due to different pharmacological activity, enantiomers of chiral drugs can differ in toxicity. Furthermore, degradation of chiral drugs during wastewater treatment and in the environment can be stereoselective and can lead to chiral products of varied toxicity. The distribution of different enantiomers of the same chiral drug in the aquatic environment and biota can also be stereoselective. Biological processes can lead to stereoselective enrichment or depletion of the enantiomeric composition of chiral drugs. As a result the very same drug might reveal different activity and toxicity and this will depend on its origin and exposure to several factors governing its fate in the environment. In this critical review a discussion of the importance of chirality of pharmacologically active compounds in the environmental context is undertaken and suggestions for directions in further research are made. Several groups of chiral drugs of major environmental relevance are discussed and their pharmacological action and disposition in the body is also outlined as it is a key factor in developing a full understanding of their environmental occurrence, fate and toxicity. This review will be of interest to environmental scientists, especially those interested in issues associated with environmental contamination with pharmacologically active compounds and chiral pollutants. As the review will outline current state of knowledge on chiral drugs, it will be of value to anyone interested in the phenomenon of chirality, chiral drugs, their stereoselective disposition in the body and environmental fate (212 references).

Sampling for pharmaceuticals and personal care products (PPCPs) and illicit drugs in wastewater systems: are your conclusions valid? A critical review

The analysis of 87 peer-reviewed journal articles reveals that sampling for pharmaceuticals and personal care products (PPCPs) and illicit drugs in sewers and sewage treatment plant influents is mostly carried out according to existing tradition or standard laboratory protocols. Less than 5% of all studies explicitly consider internationally acknowledged guidelines or methods for the experimental design of monitoring campaigns. In the absence of a proper analysis of the system under investigation, the importance of short-term pollutant variations was typically not addressed. Therefore, due to relatively long sampling intervals, potentially inadequate sampling modes, or insufficient documentation, it remains unclear for the majority of reviewed studies whether observed variations can be attributed to "real" variations or if they simply reflect sampling artifacts. Based on results from previous and current work, the present paper demonstrates that sampling errors can lead to overinterpretation of measured data and ultimately, wrong conclusions. Depending on catchment size, sewer type, sampling setup, substance of interest, and accuracy of analytical method, avoidable sampling artifacts can range from "not significant" to "100% or more" for different compounds even within the same study. However, in most situations sampling errors can be reduced greatly, and sampling biases can be eliminated completely, by choosing an appropriate sampling mode and frequency. This is crucial, because proper sampling will help to maximize the value of measured data for the experimental assessment of the fate of PPCPs as well as for the formulation and validation of mathematical models. The trend from reporting presence or absence of a compound in "clean" water samples toward the quantification of PPCPs in raw wastewater requires not only sophisticated analytical methods but also adapted sampling methods. With increasing accuracy of chemical analyses, inappropriate sampling increasingly represents the major source of inaccuracy. A condensed step-by-step Sampling Guide is proposed as a starting point for future studies.

Occurrence and fate of pharmaceuticals in wastewater treatment plants and rivers in Korea

We measured 25 pharmaceuticals in ten municipal wastewater treatment plants (WWTPs), one hospital WWTP and five rivers in Korea. In the municipal WWTP influents, acetaminophen, acetylsalicylic acid and caffeine showed relatively high concentrations. The occurrence of pharmaceuticals in the wastewater seems to be influenced by production and consumption of pharmaceuticals. The hospital WWTP influent showed higher total concentrations of pharmaceuticals than the municipal WWTPs, and caffeine, ciprofloxacin and acetaminophen were dominant. In the rivers, caffeine was dominant, and the distribution of pharmaceuticals was related to the inflow of the wastewater. In the municipal WWTPs, the concentrations of acetaminophen, caffeine, acetylsalicylic acid, ibuprofen and gemfibrozil decreased by over 99%. The decrease of these pharmaceuticals occurred mainly during the biological processes. In the physico-chemical processes, the decrease of pharmaceuticals was insignificant except for some cases. In the hospital WWTP, ciprofloxacin, acetylsalicylic acid, acetaminophen and carbamazepine showed the decrease rates of over 80%.

Psychiatric pharmaceuticals in the environment

Psychiatric pharmaceuticals, such as anxiolytics, sedatives, hypnotics, and antidepressants, are among the most prescribed active substances throughout the world. The occurrence of these widely used compounds in environmental matrices (wastewaters, surface, ground and drinking waters, soils, sediments, bio-solids and tissue), as well as the first studies indicating their high persistence and toxicity to non-target organisms, justify the growing concern about these emerging environmental pollutants. Despite this increasing interest, there is a considerable lack of knowledge about the environmental fate of a large number of psychiatric pharmaceuticals and further research about this topic is needed. This paper aims to review the literature data related to the occurrence, persistence, environmental fate and toxicity for non-target organisms of this group of pharmaceuticals. The analytical methods developed for the determination of psychiatric medicines in environmental matrices are also highlighted.