Polycyclic aromatic hydrocarbons in wastewater, WWTPs effluents and in the recipient waters of Beijing, China

In this study, surface water samples from the Wenyu River and the North Canal, effluent from major wastewater treatment plants (WWTPs) in Beijing, and wastewater from open sewers that discharge directly into the river system were collected and analyzed for 16 priority USEPA polycyclic aromatic hydrocarbons (PAHs). Concentrations of these 16 PAHs ranged from 193 to 1790 ng/L in river surface waters, 245 to 404 ng/L in WWTP effluents, and 431 to 2860 ng/L in the wastewater from the small sewers. The WWTP effluent was the main contributor of dissolved PAHs to the river, while wastewater from the small sewers contributed both dissolved and suspended particulate matter-associated PAH to the river as indicated by the high dissolved organic carbon and suspended particulate matter contents in the wastewater. Although the flow from each open sewer was small, a PAH discharge as high as 44 kg/year could occur into the river from these types of sewers. This amount was equivalent to about 22 % of the PAH loads discharged into the North Canal downstream from Beijing, whereas the remainder was mainly released by the major WWTPs in Beijing.     

Spatial and seasonal distribution of selected antibiotics in surface waters of the Pearl Rivers, China

The distribution and occurrence of 15 antibiotics in surface water of the Pearl River System (Liuxi River, Shijing River and Zhujiang River) and effluents of four wastewater treatment plants (WWTPs) were investigated in two sampling events representing wet season and dry season by using rapid resolution liquid chromatography-electrospray tandem mass spectrometry (RRLC-MS/MS) in positive ionization mode. Only eight antibiotics (sulfadiazine, sulfapyridine, sulfamethazine, sulfamethoxazole, trimethoprim, roxithromycin, erythromycin-H?O and norfloxacin) were detected in the water samples of the three rivers and the effluents. The detection frequencies and levels of antibiotics in the dry season were higher than those in the wet season. This could be attributed to the dilution effects in the wet season and relatively lower temperature in the dry season under which antibiotics could persist for a longer period. The levels of the detected antibiotics in different sites are generally in a decreasing order as follows: Shijing River ≥WWTP effluent ≥Zhujiang River ≥ Liuxi River. Risk assessment based on the calculated risk quotients showed that only erythromycin-H?O and roxithromycin detected in the Pearl Rivers might have adverse effects on aquatic organisms.     

Occurrence, distribution, and seasonal variation of estrogenic compounds and antibiotic residues in Jiulongjiang River, South China

Background and purpose

Estrogenic compounds and antibiotic residues in environment are receiving significant attention because of their potential adverse effects on ecosystems and human health. The objectives of this study were to determine the occurrence and seasonal variability of eight kinds of estrogenic compounds and 14 antibiotics. The study developed an occurrence database of the estrogenic compounds and antibiotics in spatial and temporal scale in Jiulongjiang River, South China, to provide useful information for environmental management of this region.

Methods

Eight estrogenic compounds and 14 antibiotic compounds were detected in Jiulongjiang River from 19 sampling sites during high-flow and low-flow season in surface water. The samples were preconcentrated by solid-phase extraction for analysis. Eight estrogenic compounds were analyzed by gas chromatography mass spectrometry (Agilent 7890A-5975C), and antibiotics were determined by liquid chromatography-tandem mass spectrometry (LC?CMS/MS) system (ABI 3200 Q TRAP).

Results

All target compounds could be detected, except 17??-ethynylestradiol, sulfamerazine, and ofloxacin. The median concentrations for seven estrogenic compounds ranged from 6.00 to 610.72?ng/L, with the detection frequency range of 16.00?C100%. However, the detection frequencies of 13 antibiotics detected varied from 50% to 100%, with the median concentrations ranged from 0.89 to 117.97?ng/L. Seasonal variations were obvious for most estrogenic compounds in Jiulongjiang River, except for octylphenol and estriol. There were significant (P?Conclusion The Jiulongjiang River water was more seriously contaminated by diethylstilbestrol, estrone, sulfamethazine, and tetracyclines. Higher overall concentration levels of estrogenic compounds and antibiotics were detected in low-flow water than those in high-flow water. The pollution of estrogenic compounds and antibiotics in Jiulongjiang River mainly came from municipal sewage and livestock breeding activities.     

The occurrence of illicit and therapeutic pharmaceuticals in wastewater effluent and surface waters in Nebraska

The occurrence and estimated concentration of twenty illicit and therapeutic pharmaceuticals and metabolites in surface waters influenced by wastewater treatment plant (WWTP) discharge and in wastewater effluents in Nebraska were determined using Polar Organic Chemical Integrative Samplers (POCIS). Samplers were installed in rivers upstream and downstream of treated WWTP discharge at four sites and in a discharge canal at a fifth location. Based on differences in estimated concentrations determined from pharmaceuticals recovered from POCIS, WWTP effluent was found to be a significant source of pharmaceutical loading to the receiving waters. Effluents from WWTPs with trickling filters or trickling filters in parallel with activated sludge resulted in the highest observed in-stream pharmaceutical concentrations. Azithromycin, caffeine, 1,7-dimethylzanthine, carbamazepine, cotinine, DEET, diphenhydramine, and sulfamethazine were detected at all locations. Methamphetamine, an illicit pharmaceutical, was detected at all but one of the sampling locations, representing only the second report of methamphetamine detected in WWTP effluent and in streams impacted by WWTP effluent.     

Occurrence and distribution of veterinary antibiotics and tetracycline resistance genes in farmland soils around swine feedlots in Fujian Province, China

Six antibiotics, tetracyclines (TCs), and quinolones (QNs) in farmland soils from four coastal cities in Fujian Province of China were investigated. Oxytetracycline was most frequently detected, followed by enrofloxacin, ciprofloxacin, chlorotetracycline, ofloxacin, and tetracycline, with maximum concentrations of 613.2, 637.3, 237.3, 2668.9, 205.7, and 189.8 μg kg^?1, respectively. Samples from Putian City contained the highest maximum concentration of ∑TCs (3,064.2 μg kg^?1), whereas those from Fuzhou City contained the highest maximum concentration of ∑QNs (897.8 μg kg^?1). It is noteworthy that the ∑TCs and ∑QNs in 46.4 and 28.6 % of samples exceeded the ecotoxic effect trigger value (100 μg kg^?1), respectively. The concentrations of these antibiotics and five tetracycline resistance genes in four soil plots at depth profiles were quantified thereafter. In most cases, both antibiotics and resistance genes decreased with the increase of depth. Some antibiotics can be detected at a depth of 60–80 cm where the abundance of tetO, tetM, and tetX reached up to 10⁷ copies g^?1. Additionally, the sum of all tet genes (normalized to 16S rRNA genes) correlated with ∑TCs significantly (r?=?0.676). Our results suggest that resistance determinants can migrate to deeper soil layers and would probably contaminate groundwater by vertical transport.     

Spatial and seasonal distribution of selected antibiotics in surface waters of the Pearl Rivers,China

The distribution and occurrence of 15 antibiotics in surface water of the Pearl River System (Liuxi River, Shijing River and Zhujiang River) and effluents of four wastewater treatment plants (WWTPs) were investigated in two sampling events representing wet season and dry season by using rapid resolution liquid chromatography–electrospray tandem mass spectrometry (RRLC-MS/MS) in positive ionization mode. Only eight antibiotics (sulfadiazine, sulfapyridine, sulfamethazine, sulfamethoxazole, trimethoprim, roxithromycin, erythromycin-H₂O and norfloxacin) were detected in the water samples of the three rivers and the effluents. The detection frequencies and levels of antibiotics in the dry season were higher than those in the wet season. This could be attributed to the dilution effects in the wet season and relatively lower temperature in the dry season under which antibiotics could persist for a longer period. The levels of the detected antibiotics in different sites are generally in a decreasing order as follows: Shijing River ?WWTP effluent ?Zhujiang River ? Liuxi River. Risk assessment based on the calculated risk quotients showed that only erythromycin-H₂O and roxithromycin detected in the Pearl Rivers might have adverse effects on aquatic organisms.     

Fate of selected pharmaceuticals in hospital and municipal wastewater effluent: occurrence,removal, and environmental risk assessment

The concentrations and distribution of β-blockers, lipid regulators, and psychiatric and cancer drugs in the influent and effluent of the municipal wastewater treatment plant (WWTP) and the effluent of 16 hospitals that discharge into the wastewater treatment plant mentioned in this study at two sampling dates in summer and winter were examined. The pharmaceutical contribution of hospitals to municipal wastewater was determined. The removal of target pharmaceuticals was evaluated in a WWTP consisting of conventional biological treatment using activated sludge. Additionally, the potential environmental risk for the aquatic receiving environments (salt lake) was assessed. Beta-blockers and psychiatric drugs were detected in high concentrations in the wastewater samples. Atenolol (919 ng/L) from β-blockers and carbamazepine (7008 ng/L) from psychiatric pharmaceuticals were detected at the highest concentrations in hospital wastewater. The total pharmaceutical concentration determined at the WWTP influent and effluent was between 335 and 737 ng/L in summer and between 174 and 226 ng/L in winter. The concentrations detected in hospital effluents are higher than the concentrations detected in WWTP. The total pharmaceutical contributions from hospitals to the WWTP in summer and winter were determined to be 2% and 4%, respectively. Total pharmaceutical removal in the WWTP ranged from 23 to 54%. According to the risk ratios, atenolol could pose a high risk (risk quotient > 10) for fish in summer and winter. There are different reasons for the increase in pharmaceutical consumption in recent years. One of these reasons is the COVID-19 pandemic, which has been going on for 2 years. In particular, hospitals were operated at full capacity during the pandemic, and the occurrence and concentration of pharmaceuticals used for the therapy of COVID-19 patients has increased in hospital effluent. Pandemic conditions have increased the tendency of people to use psychiatric drugs. It is thought that beta-blocker consumption has increased due to cardiovascular diseases caused by COVID-19. Therefore, the environmental risk of pharmaceuticals for aquatic organisms in hospital effluent should be monitored and evaluated.

     

Determination of fluoroquinolone antibiotics in wastewater effluents by liquid chromatography-mass spectrometry and fluorescence detection

The occurrence of quinolone antibiotics (QAs) was investigated in wastewater effluents and surface river/lake waters in the US and Canada by using solid-phase extraction with mixed phase cation exchange disk cartridge and liquid chromatography-mass spectrometry (LC-MS) and liquid chromatography fluorescence detection (LC-FLD). Ofloxacin (OFL) was detected in secondary and final effluents of a wastewater treatment plant (WWTP) in East Lansing, Michigan, at concentrations of 204 and 100 ng/l, respectively. The mass flow calculation, estimated by multiplying the OFL concentration in the final effluent by the average influent volume of the WWTP, showed that the discharge of OFL to the river was 4.8 g/day. The OFL concentrations in wastewater effluents measured in this study are comparable to or less than those observed in several European countries. QAs were not detected in river and lake waters analyzed in this study, which may due to dilution effects and to the higher detection limits, relative to those reported previously. OFL concentrations were approximately 1-2 orders of magnitude lower than the EC50 concentrations for environmental bacterium. However, greater concentrations of other QAs in sewage sludge from WWTPs may result in cumulative effects. Considering that the sewage sludge is applied to the land as fertilizers, soil-dwelling organisms could experience greater exposures to such antibiotics. Monitoring studies of QAs in sewage from WWTPs and in sediment/soil near aquaculture facilities and livestock farms will be necessary for the evaluation of the environmental distribution and risk of these compounds.     

LC-MS-MS analysis and occurrence of octyl- and nonylphenol, their ethoxylates and their carboxylates in Belgian and Italian textile industry, waste water treatment plant effluents and surface waters

Alkylphenols (APs), alkylphenol ethoxylates (APEOs), ethoxycarboxylate metabolites (APECs) and bisphenol A were determined in surface water using solid-phase extraction (SPE) followed by triple-quadrupole LC-MS-MS. APs were separated by LC from APECs using an acetonitrile-water-gradient without the addition of any buffer. Nonylphenol ethoxycarboxylates (NPECs) interfere in the detection of nonylphenols (NPs) when using an acidic mobile phase, because they produce the same MS-MS fragment ions (219>133 and 147). 4n-NP shows the characteristic transition 219>106; it is well suited as internal standard. Nonylphenol ethoxylates NPE(n)Os (n=1-17) were analysed separately in a second run by positive ionization using an ammonium acetate mobile phase. Textile industry discharges, the corresponding wastewater treatment plant (WWTP) effluents and the receiving rivers in Belgium and Italy were analysed. Among the substances investigated, NPE1C and NPE2O exhibited the highest concentrations in the water samples, up to 4.5 microg l(-1) NPE1C in a WWTP effluent and 3.6 microg l(-1) NPE2O in a river. The highest NP levels were found in the receiving rivers (max. 2.5 microg l(-1)). The predicted no-effect concentration (PNEC) for NP of 0.33 microg l(-1) for water species was frequently exceeded in the surface waters investigated, suggesting potential adverse effects to the aquatic environment.     

Acidic pharmaceuticals in domestic wastewater and receiving water from hyper-urbanization city of China (Shanghai): environmental release and ecological risk

The occurrence, behavior, and release of five acidic pharmaceuticals, including ibuprofen (IBP), naproxen (NPX), ketoprofen (KEP), diclofenac (DFC), and clofibric acid (CA), have been investigated along the different units in a tertiary-level domestic wastewater treatment plant (WWTP) in hyper-urbanization city of China (Shanghai). IBP was the most abundant chemicals among the measured in raw wastewater. The loads of the acidic pharmaceuticals in the WWTP influent ranged from 7.5 to 414 mg/day/1,000 inh, which were lower than those reported in the developed countries suggesting a less per capita consumption of pharmaceuticals in Shanghai. IBP obtained by highest removal (87 %); NPX and KEP were also significantly removed (69–76 %). However, DFC and CA were only moderately removed by 37–53 %, respectively. Biodegradation seemed to play a key role in the elimination of the studied pharmaceuticals except for DFC and CA. An annual release of acidic pharmaceuticals was estimated at 1,499 and 61.7 kg/year through wastewater and sludge, respectively, from Shanghai. Highest pharmaceuticals concentrations were detected in the effluent discharge point of the WWTP, indicating that WWTP effluent is the main source of the acidic pharmaceuticals to its receiving river. Preliminary results indicated that only DFC in river had a high risk to aquatic organisms. Nevertheless, the joint toxicity effects of these chemicals are needed to further investigate.     

Environmental exposure of pharmaceuticals and musk fragrances in the Somes River before and after upgrading the municipal wastewater treatment plant Cluj-Napoca,Romania

Background, aim, and scope

Pharmaceutically active substances are a class of emerging contaminants, which has led to increasing concern about potential environmental risks. After excretion, substantial amounts of unchanged pharmaceuticals and their metabolites are discharged into domestic wastewaters. The absence of data on the environmental exposure in Eastern Europe is significant, since use patterns and volumes differ from country to country. In Romania, the majority of wastewater, from highly populated cities and industrial complex zones, is still discharged into surface waters without proper treatment or after inefficient treatment. In respect to this, it is important to determine the environmental occurrence and behavior of pharmaceuticals and personal care products (PPCPs) in wastewaters and surface waters. The objective of the present study was to investigate the occurrence of selected PPCPs during the transport in the Somes River by mass flow analysis before and after upgrading a municipal wastewater treatment plant (WWTP) in Cluj-Napoca, which serves 350,000 inhabitants and is the largest plant discharging into the Somes River. The concentrations of PPCPs at Cluj-Napoca can be correlated with the high population and a high number of hospitals located in the catchment area leading to higher mass flows. The results of this study are expected to provide information, with respect to the Romanian conditions, for environmental scientists, WWTP operators, and legal authorities. The data should support the improvement of existing WWTPs and implementation of new ones where necessary and, therefore, minimize the input of contaminants into ambient waters.

Materials and methods

The PPCPs were selected on the basis of consumption at the regional scale, reported aquatic toxicity, and the suitability of the gas chromatography/mass spectrometry (GC/MS) method for the determination of the compounds at trace levels. The studied PPCPs, caffeine (stimulant), carbamazepine (antiepileptic), pentoxifylline (anticoagulant), cyclophosphamide (cytostatic), ibuprofen (analgesic), and galaxolide (musk fragrance), were determined in samples of the Somes River. The analytes were enriched by solid-phase extraction and subsequently determined by GC/MS. Caffeine, pentoxifylline, and galaxolide were determined underivatized, whereas the acidic pharmaceuticals carbamazepine, cyclophosphamide, and ibuprofen were determined after derivatization with N-methyl-N-(trimethylsilyl)-trifluoroacetamide.

Results and discussion

The concentrations in the Somes River varied from below 10 ng/L up to 10 μg/L. A substantial decrease of the exposure in the Somes River could be observed due to the upgrade of the municipal WWTP in Cluj-Napoca. The loads in the river stretch between Cluj-Napoca and Dej (Somes Mic) varied strongly: caffeine (400–2,000 g/day), carbamazepine (78–213 g/day), galaxolide (140–684 g/day), ibuprofen (84–108 g/day). After the upgrade of the WWTP Cluj-Napoca, the concentrations in the Somes of caffeine, pentoxifylline, cyclophosphamide, galaxolide, and tonalide were significantly reduced (over 75%). One might be cautious comparing both studies because the relative efficiency of the WWTP’s removal of PPCP was not evaluated. However, the significantly lower concentrations of most compounds after the upgrade of the WWTP Cluj-Napoca allow one to infer that the technical measures at the source substantially reduced inputs of contaminants to the receiving river. Dej loads of the poorly biodegradable substance carbamazepine increased by a factor of 2–3 as a result of wastewater discharges into the river. The disproportionate increase in caffeine loads by a factor of 4 below Cluj-Napoca indicates inputs of untreated wastewater from the Somes Mare due to the discharge of untreated wastewater derived from Bistrita, Nasaud, and Beclean (115,000 inhabitants).

Conclusions

The relative contribution of treated and untreated wastewater in surface water might be assessed by measuring chemical markers. Recalcitrant pharmaceuticals like carbamazepine are suitable as chemical markers for estimating the relative contribution of wastewater in surface water. The easily degradable caffeine might be a good indicator for raw sewage and hardly treated wastewaters.

Recommendations and perspectives

Municipal WWTPs have the potential of a significant contribution in reducing the load of contaminants to ambient waters. The efficiency of the wastewater treatment in Cluj-Napoca improved considerably after the upgrade of the WWTP. Therefore, it is crucial that several WWTPs must be implemented or improved in the Somes Valley Watershed in order to reduce the discharge of contaminants in the Somes River from these point sources.

     

Determination of estrogenic compounds in wastewater using liquid chromatography-tandem mass spectrometry with electrospray and atmospheric pressure photoionization following desalting extraction

Two complementary LC-MS ionization methods, electrospray (ESI) and atmospheric pressure photoionization (APPI), have been optimized to determine three natural estrogenic compounds (estrone, 17beta-estradiol and estriol) and two synthetic estrogenic compounds (17alpha-ethynylestradiol and diethylstilbestrol) in the influent and effluent of wastewater treatment plants (WWTPs). The wastewater samples were first subjected to solid-phase extraction coupled with desalting extraction to remove matrix interference. The analytes were then detected using liquid chromatography-tandem mass spectrometry (LC-MS-MS) with ESI and dopant-assisted (DA) APPI to evaluate the ion suppression effect and to complement the detection and quantification of estrogenic compounds in complex wastewater samples. The average ion suppression factors for the extracts of the WWTP influent analyzed using ESI and APPI were 52+/-5% and 27+/-7%, respectively. The sensitivity and ionization efficiency of the LC-ESI-MS-MS system decreased dramatically when a complex matrix was present in the WWTP influent sample. Estrogenic compounds could be detected in the WWTP influent and effluent samples at concentrations below the parts-per-billion level. The lower detection limits obtained when using ESI and the higher matrix tolerance of the APPI method allowed the complete quantification of estrogenic compounds in very complex samples in a complementary manner.     

Plasma vitellogenin in male teleost fish from 43 rivers worldwide is correlated with upstream human population size

It has been previously demonstrated that vitellogenin (VTG) - a precursor egg yolk protein - is produced in male fish exposed to estrogenic compounds in wastewater treatment plant (WWTP) effluent. However, little attention has been given to examine whether any patterns of male VTG production exists across fish species on a global scale. We hypothesized that a composite measure of human population size over river discharge would best explain variations of protein levels in male fish. We compiled VTG data in 13 fish species from 43 rivers receiving municipal WWTP effluent on 3 continents. We found that human population size explained 28% of the variation in male VTG concentrations, whereas population/flow rate failed to significantly correlate with VTG. We suggest this result may be explained by the low solubility of estrogenic compounds, resulting in localized contamination near WWTP outfalls, rather than dilution by river water.     

Occurrence of estrogenic effects in sewage and industrial wastewaters in Beijing, China

Estrogenic potencies of the effluents or water samples from wastewater treatment plants (WWTPs), industries and hospitals and some receiving rivers in Beijing city were estimated by using a human estrogen receptor recombinant yeast assay. Estrogenic activity of industrial wastewaters was found to range from 0.1 to 13.3 ng EEQ/L and decreased to the range of 0.03-1.6 ng EEQ/L after treatment. Estrogenic activity in WWTP influent ranged from 0.3 to 1.7 ng EEQ/L and decreased to the range of 0.05-0.5 ng EEQ/L after treatment. In the receiving river waters, the estrogenic effect range was 0.1-4.7 ng EEQ/L. These data suggest that treated industrial effluents and WWTP effluents of concern are not the only source of estrogenic pollution in surface waters in Beijing city. EEQ levels in Beijing river water are likely attributable to untreated municipal and industrial wastewaters discharged directly into the river.     

Occurrence,distribution, and multi-phase partitioning of triclocarban and triclosan in an urban river receiving wastewater treatment plants effluent in China

Occurrence, distribution, spatial and seasonal variations, and partitioning between aqueous phase and suspended particulate matters (SPM) of triclocarban (TCC) and triclosan (TCS) in Xiaoqing River, which receives wastewater treatment plant (WWTP) effluents, were studied. The distribution of the total TCC and TCS levels in surface water and sediments along the river were discussed. The highest TCC and TCS concentrations were both found near the discharge port of WWTPs, and the TCC and TCS levels decreased downstream of the WWTPs as a result of their distances from the source of WWTP discharges. The mean values of TCC and TCS in low-flow season were 1.62 and 1.80 times, respectively, as much as in high-flow season in surface water. The study on partitioning of TCC and TCS between aqueous phase and SPM shown the mean level of dissolved TCC accounted for about 10 % of the total level in surface water, whereas the TCS level was about 30 %. The TCC concentrations detected in the surface sediment samples (0 to 5 cm) ranged from 226 to 1,956 ng/g, with a mean value of 733 ng/g. The TCS levels were between 85 and 705 ng/g, with a mean value of 255 ng/g. The distribution and variations of TCC and TCS in sediments along the river were highly consistent with those in the water phase. The TCC and TCS levels in deep sediments (5 to 10 cm) were significantly lower than those in surface sediments. The mean TCC level in surface sediments was about 2.4 times as much as in deep sediments, and the TCS level in surface sediments was 3.1 times as much as in deep sediments.     

Determination of selected antibiotics in the Victoria Harbour and the Pearl River, South China using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry

Nine selected antibiotics in the Victoria Harbour of Hong Kong and the Pearl River at Guangzhou, South China, were analyzed using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry. The results showed that the concentrations of antibiotics were mainly below the limit of quantification (LOQ) in the marine water of Victoria Harbour. However, except for amoxicillin, all of the antibiotics were detected in the Pearl River during high and low water seasons with the median concentrations ranging from 11 to 67 ng/L, and from 66 to 460 ng/L, respectively; and the concentrations in early spring were about 2-15 times higher than that in summer with clearer diurnal variations. It was suggested that the concentrations of antibiotics in the high water season were more affected by wastewater production cycles due to quick refreshing rate, while those in the low water season may be more sensitive to the water column dynamics controlled by tidal processes in the river.     

Occurrence of steroid hormones and antibiotics in shallow groundwater impacted by livestock waste control facilities

Wastewater impoundments at concentrated animal feeding operations (CAFOs) represent a potential source of veterinary pharmaceuticals and steroid hormone contamination to shallow groundwater. This study investigates the occurrence of seventeen veterinary pharmaceuticals and thirteen steroid hormones and hormone metabolites in lagoons and adjacent groundwater at operating swine and beef cattle facilities. These sites were chosen because subsurface geology and previous monitoring of nitrate, ammonia and chloride levels in shallow ground water strongly indicated direct infiltration, and as such represent worst cases for ground water contamination by waste water. Pharmaceutical compounds detected in samples obtained from cattle facilities include sulfamerazine; sulfamethazine; erythromycin; monensin; tiamulin; and sulfathiazole. Lincomycin; ractopamine; sulfamethazine; sulfathiazole; erythromycin; tiamulin and sulfadimethoxine were detected in wastewater samples obtained from swine facilities. Steroid hormones were detected less frequently than veterinary pharmaceuticals in this study. Estrone, testosterone, 4-androstenedione, and androsterone were detected in wastewater impoundments at concentrations ranging from 30 to 3600ng/L, while only estrone and testosterone were detected in groundwater samples at concentrations up to 390ng/L. The co-occurrence of veterinary pharmaceutical and steroid hormone contamination in groundwater at these locations and the correlation between pharmaceutical occurrence in lagoon wastewater and hydraulically downgradient groundwater indicates that groundwater underlying some livestock wastewater impoundments is susceptible to contamination by veterinary pharmaceuticals and steroid hormones originating in wastewater lagoons.     

Impact of wastewater treatment plants on receiving surface waters and a tentative risk evaluation: the case of estrogens and beta blockers

Five estrogenic hormones (unconjugated?+?conjugated fractions) and 10 beta blockers were analyzed in three wastewater treatment plant (WWTP) effluents and receiving river waters in the area of Lyon, France. In the different samples, only two estrogens were quantified: estrone and estriol. Some beta blockers, such as atenolol, acebutolol, and sotalol, were almost always quantified, but others, e.g., betaxolol, nadolol, and oxprenolol were rarely quantified. Concentrations measured in river waters were in the nanogram per liter range for estrogens and between 0.3 and 210 ng/L for beta blockers depending on the substance and the distance from the WWTP outfall. The impact of the WWTP on the receiving rivers was studied and showed a clear increase in concentrations near the WWTP outfall. For estrogens, the persistence in surface waters was not evaluated given the low concentrations levels (around 1 ng/L). For beta blockers, concentrations measured downstream of the WWTP outfall were up to 16 times higher than those measured upstream. Also, the persistence of metoprolol, nadolol, and propranolol was noted even 2 km downstream of the WWTP outfall. The comparison of beta blocker fingerprints in the samples collected in effluent and in the river also showed the impact of WWTP outfall on surface waters. Finally, a tentative environmental risk evaluation was performed on 15 sites by calculating the ratio of receiving water concentrations to predicted non-effect concentrations (PNEC). For estrogens, a total PNEC of 5 ng/L was considered and these substances were not linked to any potential environmental risk (only one site showed an environmental risk ratio above 1). Unfortunately, few PNECs are available and risk evaluation was only possible for 4 of the 10 beta blockers studied: acebutolol, atenolol, metoprolol, and propranolol. Only propranolol presented a ratio near or above 1, showing a possible environmental risk for 4 receiving waters out of 15.     

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.     

Combination of in vitro bioassays for the determination of cytotoxic and genotoxic potential of wastewater, surface water and drinking water samples

In this study we evaluated genotoxicity and cytotoxicity of native samples of wastewaters (15 samples), surface waters (28 samples) and potable waters (8 samples) with the SOS/umuC assay with Salmonella typhimurium TA1535/pSK1002 and MTT assay with human hepatoma HepG2 cells. The genotoxicity of selected samples was confirmed with the comet assay with HepG2 cells. In the SOS/umuC assay 13 out of the 51 samples were genotoxic: two effluent samples from chemical industry; one sample of wastewater treatment plant effluent; two hospital wastewater samples; three river water samples and four lake water samples. Six samples were cytotoxic for HepG2 cells: both effluent samples of chemical industry, two wastewater treatment plant effluent samples, and two river water samples, however, only the chemical industry effluent samples were genotoxic and cytotoxic, indicating that different contaminants are responsible for genotoxic and toxic effects. Comparing genotoxicity of river and lake water samples with the chemical analytical data of the presence of the residues of pharmaceutical and personal care products (non-steroidal anti-inflammatory drugs, UV filters and disinfectants) in these samples, indicated that the presence of UV filters might be linked to the genotoxicity of these samples. The results showed that the application of the bacterial SOS/umuC assay and mammalian cell assays (MTT and comet assay) with HepG2 cells was suitably sensitive combination of assays to monitor genotoxicity and cytotoxicity of native samples of wastewaters and surface waters. With this study we also confirmed that the toxicity/genotoxicity bioassays should be an integral tool in the evaluation of toxicity of complex wastewaters before the release into environment, as well as for the monitoring of surface water quality, providing data useful in risk assessment.