Rapid determination of free and conjugated estrogen in different water matrices by liquid chromatography-tandem mass spectrometry

Occurrence and environmental fate of anti-influenza drugs in a subcatchment of the Yodo River Basin, Japan

Understanding the current situation and risk of environmental contamination by anti-influenza drugs in aquatic environments is key to prevent the unexpected emergence and spread of drug-resistant viruses. However, few reports have been focused on newer drugs that have recently been introduced in clinical settings. In this study, the behaviour of the prodrug baloxavir marboxil (BALM)-the active ingredient of Xofluza, an increasingly popular anti-influenza drug-and its pharmacologically active metabolite baloxavir (BAL) in the aquatic environment was evaluated. Additionally, their presence in urban rivers and a wastewater treatment plant (WWTP) in the Yodo River basin was investigated and compared with those of the major anti-influenza drugs used to date (favipiravir (FAV), peramivir (PER), laninamivir (LAN), and its active metabolite, laninamivir octanoate (LANO), oseltamivir (OSE), and its active metabolite, oseltamivir carboxylate (OSEC), and zanamivir (ZAN)) to comprehensively assess their environmental fate in the aquatic environment. The results clearly showed that BALM, FAV, and BAL were rapidly degraded through photolysis (2-h, 0.6-h, and 0.4-h half-lives, respectively), followed by LAN, which was gradually biodegraded (7-h half-life). In addition, BALM and BAL decreased by up to 47 % after 4 days and 34 % after 2 days of biodegradation in river water. However, the remaining conventional drugs, except for LANO (<1 % after 10 days), were persistent, being transported from the upstream to downstream sites. The LogKd values for the rates of sorption of BALM (0.5-1.6) and BAL (1.8-3.1) on river sediment were higher than those of conventional drugs (-0.5 to 1.7). Notably, all anti-influenza drugs were effectively removed by ozonation (>90-99.9 % removal) after biological treatment at a WWTP. Thus, these findings suggest the importance of introducing ozonation to reduce pollution loads in rivers and the environmental risks associated with drug-resistant viruses in aquatic environments, thereby promoting safe river environments.

Multiphase Partitioning of Estrogens in a River Impacted by Feedlot Wastewater Discharge

Estrogens in river systems can significantly impact aquatic ecosystems. This study aimed to investigate the multiphase partitioning of estrogens in Wulo Creek, Taiwan, which receives animal feedlot wastewater, to understand their distribution and potential environmental implications. Water samples were separated into suspended particulate matter (SPM), colloidal, and soluble phases using centrifugation and cross-flow ultrafiltration. Concentrations of estrone (E1), 17β-estradiol (E2), and estriol (E3) in each phase were analyzed using LC/MS/MS. Partition coefficients were calculated to assess estrogen distribution among phases. Estrogens were predominantly found in the soluble phase (85.8-87.3%). The risk assessment of estrogen equivalent (EEQ) values suggests that estrogen concentration in water poses a higher risk compared to SPM, with a majority of the samples indicating a high risk to aquatic organisms. The colloidal phase contained 12.7-14.2% of estrogens. The log KCOC values (4.72-4.77 L/kg-C) were significantly higher than the log KOC and log KPOC values (2.02-3.40 L/kg-C) for all estrogens. Colloids play a critical role in estrogen distribution in river systems, potentially influencing their fate, transport, and biotoxicity. This finding highlights the importance of considering colloidal interactions in assessing estrogen behavior in aquatic environments.

Combined collection systems of sewage and rainfall runoff seriously affect the spatial distributions of natural estrogens and their conjugates in river water: Insights from the Pearl River of China

So far, little has been known about how the combined collection systems of sewage and rainfall runoff (CCSs) affect emerging contaminants in river water. To fill up the knowledge gap, this study was conducted to investigate the spatial distributions of three natural estrogens (NEs, i.e., estrone (E1), 17β-estradiol (E2) and estriol (E3)) and their conjugates (C-NEs) in the Pearl River in the wet and dry seasons. Results showed that the respective average concentrations of NEs and C-NEs at different locations alongside the Pearl River in the wet season were 7.3 and 1.8 times those in the dry season. Based on estrogen equivalence (EEQ), the average estimated EEQ level in the Pearl River waters in the wet season was nearly 10 times that in the dry season. These seemed to imply that the CCSs in the wet season not only cause untreated sewage into the receiving water body, but greatly decrease the removal efficiency of NEs and C-NEs in wastewater treatment plant. Furthermore, the estimated annual loads of E1, E2, and E3 to the Pearl River in the wet season accounted for about 88.6 %, 100 %, and 99.3 % of the total annual loads. Consequently, this work for the first time demonstrated that the CCSs in cities with high precipitation are unfavorable for controlling of emerging contaminants.

Simultaneous trace determination of three natural estrogens and their sulfate and glucuronide conjugates in municipal waste and river water samples with UPLC-MS/MS

Analytical method for three natural estrogens (NEs) and their sulfate and glucuronide conjugates in waste and river waters using solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) has been available, but problems including poor recovery exist. In order to solve these, some optimizations have been performed in this work. For sample preparation, both rinse and elution solutions were optimized, in which 6 mL of MeOH/water (1:9, v/v), MeOH/Ace/water (10:2:88, v/v/v), and MeOH/NH₄OH/water (10:2:88, v/v/v) were determined as the rinse solution, while 6 mL of 2.0% NH₄OH/MeOH was determined as the elution solution for conjugated NEs (C-NEs). For mobile phase, addition of NH₄F could obviously enhance the signal response of the nine target compounds, and the optimized addition concentration was 0.5 mmol/L. The developed efficient method was validated and showed excellent linearity for each target compound (R² > 0.998), low limit of quantifications (LOQs, 0.07-1.29 ng/L) in four different water matrices, and excellent recovery efficiencies of 81.0-116.1% in influent, effluent, ultra-pure, and river water samples with low relative standard deviations (RSDs, 0.6-13.6%). The optimized method was successfully applied to influent, effluent, and Pearl River water, among which three NEs were all detected, while five C-NEs were found in the influent, three C-NEs were detected in the effluent, and two C-NEs were found in the Pearl River water, indicating the wide distribution of NEs and C-NEs in different water environments. This work provided a reliable and efficient analytical method for simultaneous trace determination of NEs and C-NEs, which had satisfactory absolute recoveries with low RSDs, low LOQs, and time-saving for both analysis and nitrogen drying.

Investigation of free and conjugated estrogen fate and emission coefficients in three duck farms

Concentration animal feeding operation (CAFO) is an important source of environmental estrogen. However, to the best of our knowledge, the data on estrogen discharge during duck breeding and growth is insufficient. This study used liquid chromatography with tandem mass spectrometry (LC/MS/MS) to analyze the free and conjugated estrogen concentrations in the surface water, outlet water, groundwater, and duck manure/soil mixture at three duck farms in Taiwan. Natural estrogen species included estrone (E1), 17β-estradiol (E2), estriol (E3), estrone-3-sulfate (E1-3S), 17β-estradiol-3-sulfate (E2-3S), estrone-3-glucuronide (E1-3G), and 17β-estradiol-3-glucuronide (E2-3G), whereas synthetic estrogen included 17α-ethynylestradiol (EE2) and diethylstilbestrol (DES). This study showed that the total estrogen concentrations in the surface water and groundwater were 15.4 and 4.5 ng/L, respectively, which constituted 56% and 58%, respectively, conjugated estrogen. From the pond to the outlet water, the total estrogen concentration decreased by 3.9 ng/L (23% loss) in the duck farms. However, the estrogenic potency was slightly reduced from 0.91 to 0.88 E2 equivalent/L, showing a negligible decrease. From the pond to the outlet water, the field results showed that converting the conjugated estrogen into free estrogen in the duck farm-released water increased their environmental hazard. Primarily E1, with an average concentration of 0.9 ± 1.6 ng/g, was present in the duck manure. The estrogen excreted by the ducks in the pond (from surface water to outlet water) was estimated to be 0.18 kg/million head-year. Although the estrogen concentration in the duck farms was low, the environmental impact of CAFO should not be neglected.

Evaluation of the Correspondence between the Concentration of Antimicrobials Entering Sewage Treatment Plant Influent and the Predicted Concentration of Antimicrobials Using Annual Sales, Shipping, and Prescriptions Data

The accuracy and correspondence between the measured concentrations from the survey and predicted concentrations on the basis of the three types of statistical antimicrobial use in Japan was evaluated. A monitoring survey of ten representative antimicrobials: ampicillin (APL), cefdinir (CDN), cefpodoxime proxetil (CPXP), ciprofloxacin (CFX), clarithromycin (CTM), doxycycline (DCL), levofloxacin (LFX), minocycline (MCL), tetracycline (TCL), and vancomycin (VMC), in the influent of sewage treatment plant (STP) located in urban areas of Japan, was conducted. Then, the measured values were verified in comparison with the predicted values estimated from the shipping volumes, sales volumes, and prescription volumes based on the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB). The results indicate that the correspondence ratios between the predicted concentrations calculated on the basis of shipping and NDB volumes and the measured concentrations (predicted concentration/measured concentration) generally agreed for the detected concentration of antimicrobials in the STP influent. The correspondence ratio on the basis of shipping volume was, for CFX, 0.1; CTM, 2.9; LFX, 0.5; MCL, 1.9; and VMC, 1.7, and on the basis of NDB volume the measured concentration was CFX, 0.1; CTM, 3.7; DCL, 0.4; LFX, 0.7; MCL, 1.9; TCL, 0.6; and VMC, 1.6. To our knowledge, this is the first report to evaluate the accuracy of predicted concentrations based on sales, shipping, NDB statistics and measured concentrations for antimicrobials in the STP influent.

Stability properties of natural estrogen conjugates in different aqueous samples at room temperature and tips for sample storage

It is important to keep natural estrogen conjugates (C-NEs) intact in aqueous environmental sample before sample preparation; otherwise, this may influence the accurate determination of NEs. Therefore, this work thoroughly investigated the stability of C-NEs in three different aqueous environmental samples under four different storage conditions, room temperature, low temperature of 4 °C, low pH of 3, and addition of HgCl₂ at 2 g/L. Results showed that C-NEs in aqueous sample were easily deconjugated under low temperature of 4 °C, which has been widely used in sample collection and storage. Both the low pH of 3 and addition of HgCl₂ at 2 g/L under room temperature could keep C-NEs intact in domestic wastewaters and river water within 36 h, but the latter could keep C-NEs stable longer. This work is the first to show that low pH of 3 alone could keep C-NEs intact, which suggested that the combined condition at low temperature of 4 °C that has been widely used could be omitted. Meanwhile, compared to pH adjustment, addition of 2 g/L HgCl₂ into aqueous sample is more convenient and practical for 24-h composite sampling, which may be widely applied.

Assessment of automated off-line solid-phase extraction LC-MS/MS to monitor EPA priority endocrine disruptors in tap water, surface water, and wastewater

EPA method 539.1 recently introduced an expanded list of priority endocrine-disrupting compounds (EDCs), some of which were also included in the Unregulated Contaminant Monitoring Rule 3 (UCMR3). Though standardized methods are available for drinking water, analysis of steroid hormones and bisphenol A (BPA) at the ultra-trace level remains challenging. This study set out to evaluate the suitability of automated off-line solid-phase extraction (SPE) liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) for the determination of EPA-priority EDCs in environmental water matrixes (tap water, surface water, and wastewater influents and effluents). The target molecules included 14 steroid hormones (altrenogest, androstenedione, equilenin, equilin, α-estradiol, β-estradiol, estriol, estrone, ethinylestradiol, levonorgestrel, medroxyprogesterone, norethindrone, progesterone, testosterone) and BPA. Factors that may influence the analytical performance were assessed. This involved, for instance, testing combinations of SPE materials from different brands and protocol variations. Several materials presented absolute extraction efficiencies in acceptable ranges. Initial sample pH, nature of reconstitution medium, and mobile phase salt concentration were among the potential factors affecting analyte signal. Storage conditions (different preservative agents) possibly exerted the strongest influence, in agreement with the literature. Limits of detection were in the range of 0.03-0.5 ng/L in drinking water, 0.1-0.5 ng/L in surface water, and 0.16-1 ng/L in wastewater. Method validation also involved testing linearity, accuracy, and precision in reagent water and matrix-matched extracted calibrants. The method was applied to field-collected water samples in Eastern Canada. Summed EDC concentrations remained low in tap water (<LOQ-0.92 ng/L), while higher detection frequencies and contamination levels were reported in riverine surface waters (2.6-37 ng/L) and municipal wastewaters (10-424 ng/L).

Occurrence and distribution of estrogenic substances in the northern South China Sea

Estrogenic substances are today among the contaminants of emerging concern. Besides naturally occurring estrogens, other natural and synthetic substances can mimic a hormonal action due to their structural resemblance to hormones, possibly affecting the endocrine system of living organisms. Estrogens have been detected in inland water bodies such as influents and effluents of waste water treatment plants as well as in rivers, but data on their distribution and variability in the marine ecosystem are still limited. Surface water samples obtained during two research cruises on the northern shelf of the South China Sea (SCS) near the Pearl River Estuary, in September 2018 and in August 2019, were investigated for estrogenic substances, namely estrone (E1), 17β-estradiol (E2), 17α-ethinylestradiol (EE2), genistein (GEN), daidzein (DAI) and zearalenone (ZEN). Among the target analytes, the natural hormones E1 and E2, as well as the synthetic EE2, were the most abundant with maximum concentrations of 1.1 ng L^-1, 0.7 ng L^-1 and 0.6 ng L^-1, respectively. Of substances produced by plants and fungi, GEN, DAI and ZEN, only GEN was detected (1.2 ng L^-1). High concentrations occurred predominantly close to the coast, which was also reflected in the calculated estradiol equivalent quotients (up to 1.4 ng L^-1). In general, the distribution of estrogenic substances observed in both years shows a regional and inter-annual variability consistent with the modeled surface current data for the SCS. Regarding single estrogenic compounds and estradiol equivalents, marine organisms in the northern SCS might be exposed to high potential risk.

Making waves: Improving removal performance of conventional wastewater treatment plants on endocrine disrupting compounds (EDCs): their conjugates matter

Endocrine disrupting compounds (EDCs) are well known emerging contaminants, which have the capacity to elicit negative effects on endocrine systems of both humans and wildlife. As the conventional wastewater treatment plants cannot stably remove these EDCs, post-treatment with advanced chemical oxidation methods such as ozonation are proven effective to further remove EDCs, but this additional treatment increase the wastewater treatment cost, which is impractical for worldwide application. To find potential alternative effective method, this work presents the importance of EDCs conjugates. Specifically, two important facts are described: 1) concentrations of EDCs conjugates in raw municipal wastewater vary with temperature, and their existence results in underestimated removal performance of WWTPs; 2) Strategies to enhance the cleavage rates of EDCs conjugates are most effective to improve the observed removal performance of conventional WWTPs on EDCs. Further work should be performed to check whether effective solutions can be found to increase their cleavage rates.

Occurrence and risk assessment of steroid estrogens in environmental water samples: A five-year worldwide perspective

The ubiquitous occurrence of steroid estrogens (SEs) in the aquatic environment has raised global concern for their potential environmental impacts. This paper extensively compiled and reviewed the available occurrence data of SEs, namely estrone (E1), 17α-estradiol (17α-E2), 17β-estradiol (17β-E2), estriol (E3), and 17α-ethinyl estradiol (EE2), based on 145 published articles in different regions all over the world including 51 countries and regions during January 2015-March 2020. The data regarding SEs concentrations and estimated 17β-estradiol equivalency (EEQ) values are then compared and analyzed in different environmental matrices, including natural water body, drinking and tap water, and wastewater treatment plants (WWTPs) effluent. The detection frequencies of E1, 17β-E2, and E3 between the ranges of 53%-83% in natural water and WWTPs effluent, and the concentration of SEs varied considerably in different countries and regions. The applicability for EEQ estimation via multiplying relative effect potency (REP_i) by chemical analytical data, as well as correlation between EEQ_bio and EEQ_cal was also discussed. The risk quotient (RQ) values were on the descending order of EE2 > 17β-E2 > E1 > 17α-E2 > E3 in the great majority of investigations. Furthermore, E1, 17β-E2, and EE2 exhibited high or medium risks in water environmental samples via optimized risk quotient (RQ_f) approach at the continental-scale. This overview provides the latest insights on the global occurrence and ecological impacts of SEs and may act as a supportive tool for future SEs investigation and monitoring.

Strategy for effective inhibition of arylsulfatase/β-glucuronidase to prevent deconjugation of sulfate and glucuronide conjugates in wastewater during sample collection and storage

Arylsulfatase and β-glucuronidase are two important enzymes that are responsible for deconjugation of estrogen conjugates. It is important to keep estrogen conjugates intact during sample collection and storage, while the effective inhibition conditions for arylsulfatase and β-glucuronidase remain unknown. To elucidate these conditions, inhibition experiments were performed by adding several inhibitors or by introducing extreme pH conditions. This work confirms that arylsulfatase and β-glucuronidase can tolerate some extremes, including high concentrations of mercury dichloride, ethanol, and EDTA, while low pH (<3) or high pH (>11) can effectively inhibit their activities. The high tolerance of arylsulfatase and β-glucuronidase for mercury dichloride explains why estrogen conjugates in wastewater samples were deconjugated, even in the extremely unfavorable condition with a high concentration of mercury dichloride. Although low pH (<3) can effectively inhibit arylsulfatase/β-glucuronidase, deconjugation of sulfate conjugates by acid hydrolysis readily occurs; thus, a high pH of 11 is an appropriate storage condition for the effective inhibition of arylsulfatase/β-glucuronidase. This appropriate storage condition was confirmed and validated with diluted and sterilized activated sludge samples in which arylsulfatase/β-glucuronidase inhibition was effective for 48 h at room temperature and with a high pH of 11. The developed appropriate storage condition for effective inhibition of arylsulfatase/β-glucuronidase has wide application potential not only for estrogen conjugates but also for all conjugates of other organic micropollutants.

Biotransformation strategies for steroid estrogen and androgen pollution

The common steroid hormones are estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2), and testosterone (T). These steroids are reported to contaminate the environment through wastewater treatment plants. Steroid estrogens are widespread in the aquatic environment and therefore pose a potential risk, as exposure to these compounds has adverse impacts on vertebrates. Excessive exposure to steroid estrogens causes endocrine disruption in aquatic vertebrates, which affects the normal sexual life of these animals. Steroid pollutants also cause several health problems in humans and other animals. Microbial degradation is an efficient method for removing hormone pollutants from the environment by remediation. Over the last two decades, microbial metabolism of steroids has gained considerable attention due to its higher efficiency to reduce pollutants from the environment. The present review is focused on the major causes of steroid pollution, concentrations of these pollutants in surface water, groundwater, drinking water, and wastewater, their effect on humans and aquatic animals, as well as recent efforts by various research groups that seek better ways to degrade steroids by aerobic and anaerobic microbial systems. Detailed overview of aerobic and anaerobic microbial biotransformation of steroid estrogens and testosterone present in the environment along with the active enzyme systems involved in these biotransformation reactions is described in the review article, which helps readers to understand the biotransformation mechanism of steroids in depth. Other measures such as co-metabolic degradation, consortia degradation, algal, and fungal steroid biotransformation are also discussed in detail.

Simultaneous UHPLC-MS/MS method of estradiol metabolites to support the evaluation of Phase-2 metabolic activity of induced pluripotent stem cell derived hepatocytes

The goal of this study was to develop and validate a high-throughput UHPLC-MS/MS method for simultaneous quantitation of three estradiol metabolites namely estradiol 3-β-D-glucuronide (E3G), estradiol 17-β-D-glucuronide (E17G) and estradiol 3-sulfate (E3S) in cell culture medium to support the characterization of metabolic function of induced pluripotent stem cell (iPSC) derived hepatocytes. To achieve this goal, a simple protein precipitation method was used for sample cleanup. All the metabolites were separated chromatographically using a C-18 column where 10 mM ammonium acetate and acetonitrile was used in gradient flow for 4 min. The analytes were quantitated by triple quadrupole mass spectrometer with the use of isotopically labeled internal standard (IS). This method was validated as per the U.S Food and Drug Administration's Bioanalytical Method Validation, Guidance for Industry. Linearity for E3G and E17G was in the range of 2-1500 ng/mL whereas for E3S it was 0.3-500 ng/mL. Inter-day and intra-day accuracy and precision of this method were in the acceptable limits. In addition, multiple stability tests (freeze thaw, autosampler, water bath (37 °C), bench top and long term) were performed for all the metabolites in cell culture medium. All the metabolites were stable up to 3 freeze thaw cycles at -20 °C and - 80 °C, 48 h in autosampler, 24 h at 37 °C, 48 h at room temperature and 173 days at -20 °C. Extraction recoveries for the metabolites were reproducible and were in the range of 94-108%. This method was used to quantitate estradiol metabolites generated by iPSC hepatocytes in-vitro studies.

Bract as a novel extraction phase in thin-film SPME combined with 96-well plate system for the high-throughput determination of estrogens in human urine by liquid chromatography coupled to fluorescence detection

In this study, an environmentally friendly and high-throughput method was developed for the determination of estrone (E1), 17β-estradiol (E2), 17α-ethinylestradiol (EE2) and estriol (E3) in human urine by liquid chromatography-fluorescence detector (HPLC-FLD). A biosorbent (bract) was proposed as extraction phase for Thin-Film SPME combined with 96-well system. The characterization of the biosorbent was performed by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The optimizations were carried out through univariate and multivariate approaches with optimal conditions comprised of urine samples diluted 40-fold, liquid desorption performed in methanol and addition of 20% (w/v) of NaCl in the sample. Considering an extraction/desorption cycle using the 96-well plate system, the sample preparation time was 1.7 min per sample, which contributes to the high-throughput of the method proposed. The analytical parameters of merit were determined and satisfactory results were achieved, including limits of detection ranging from 0.3 μg L^-1 for estradiol to 3 μg L^-1 for estrone, while limits of quantification varied from 1 μg L^-1 for estradiol to 10 μg L^-1 for estrone. The correlation coefficients ranged from 0.9947 for estrone to 0.9999 for estriol. The accuracy and intra-assay and intermediate precisions (RSD) were evaluated through extractions in diluted urine samples (40-fold) spiked with each analyte (1, 200 and 400 μg L^-1 for E3; 0.1, 200 and 400 μg L^-1 for E2; 0.5, 200 and 400 μg L^-1 for EE2 and 10, 200 and 400 μg L^-1 for E1). The relative recoveries (n = 3) ranged from 71 to 105%, intra-assay precision (n = 3) varied from 1 to 17% and intermediate precision (n = 9) ranged from 2 to 19%. The method developed can be successfully used for the quantification of estrogens in human urine samples.

Occurrence, sorption, and transformation of free and conjugated natural steroid estrogens in the environment

Natural steroid estrogens (NSEs), including free estrogens (FEs) and conjugated estrogens (CEs), are of emerging concern globally among public and scientific community due to their recognized adverse effects on human and wildlife endocrine systems in recent years. In this review, the properties, occurrence, sorption process, and transformation pathways of NSEs are clarified in the environment. The work comprehensively summarizes the occurrence of both free and conjugated estrogens in different natural and built environments (e.g., river, WWTPs, CAFOs, soil, and sediment). The sorption process of NSEs can be impacted by organic compounds, colloids, composition of clay minerals, specific surface area (SSA), cation exchange capacity (CEC), and pH value. The degradation and transformation of free and conjugated estrogens in the environment primarily involves oxidation, reduction, deconjugation, and esterification reactions. Elaboration about the major, subordinate, and minor transformation pathways of both biotic and abiotic processes among NSEs is highlighted. The moiety types and binding sites also would affect deconjugation degree and preferential transformation pathways of CEs. Notably, some intermediate products of NSEs still remain estrogenic potency during transformation process; the elimination of total estrogenic activity needs to be addressed in further studies. The in-depth researches regarding the behavior of both free and conjugated estrogens are further required to tackle their contamination problem in the ecosystem. Graphical abstract ᅟ.

Environmental fate of pharmaceutical compounds and antimicrobial-resistant bacteria in hospital effluents, and contributions to pollutant loads in the surface waters in Japan

Environmental fate of 58 pharmaceutical compounds (PhCs) grouped into 11 therapeutic classes in the three different waters, hospital effluent, sewage treatment plant (STP) and river water, was estimated by combination of their quantitative concentration analysis and evaluation of their extent of contribution as loading sources. At the same time, distribution of six classes of antimicrobial-resistant bacteria (AMRB) in the same water samples was estimated by screening of individual PhC-resistant microbes grown on each specific chromogenic medium. The results indicate that 48 PhCs were detected ranged from 1 ng/L (losartan carboxylic acid) to 228 μg/L (acetaminophen sulfate) in hospital effluent, and contribution of the pollution load derived from hospital effluent to STP influent was estimated as 0.1% to 15%. On the other hand, contribution of STP effluent to river water was high, 32% to 60% for antibacterials, antipertensives and X-ray contrast media. In the cases for AMRB, detected numbers of colonies of AMRB in hospital effluent ranged from 29 CFU/mL to 1805 CFU/mL, and the estimated contribution of the AMRB pollution load derived from hospital effluent to STP influent was as low as 0.1% (levofloxacin and olmesartan) to 5.1% (N-desmethyl tamoxifen). Although the contribution of STPs as loading sources of PhCs and AMRB in surface waters was large, ozonation as an advanced water treatment system effectively removed a wide range of both PhCs and AMRB in water samples. These results suggest the importance of reducing environmental pollutant loads (not only at STPs but also at medical facilities) before being discharged into the surface waters, to both conserve water and keep the water environment safe. To our knowledge, this is the first report to show the distribution and contribution of AMRB from hospital effluent to the surface waters.

Fate of estrogens in a pilot-scale step-feed anoxic/oxic wastewater treatment system controlling by nitrogen and phosphorus removal

The control measures for estrogens in the aquatic environment are topics of growing concern. It is a meaningful issue to finding optimal process parameters for efficient removal of estrogens with the purpose of efficient total nitrogen (TN) or total phosphorus (TP) removal in sewage treatment plants. The present paper is concerned with the relationships between the estrogen removal and TN or TP removal in a pilot-scale three-stage anoxic/oxic (A/O) system treating real municipal wastewater. The total removal efficiency for estrone (E1) and 17β-estradiol (E2) and their sulfate and glucuronide conjugates were on average 87% in the pilot-scale system. The concentrations of the sulfate and glucuronide conjugates of estrogens (E1 and E2) in the system were much lower than the estrogens, which might be caused by the rapid degradation of conjugates in the pilot-scale system. The average removal efficiencies of E1 and E2 and their sulfate and glucuronide conjugates were significantly lower under high TP removal conditions than those under high TN removal conditions that suggested that the ammonia oxidation promotes estrogen degradation. When the system achieved efficient TN removal, the concentrations of both E1 and E2 were generally lower in the aerobic zones than those in the anoxic zones. Instead, when the system achieved efficient TP removal conditions, the estrogen concentrations were higher in the aerobic zones than in the anoxic zones. However, it was thought that the variation of the concentrations of the estrogen conjugates had weak influence on concentrations of the free estrogens. The increase of the free estrogens in the aerobic zones could be attributed to the release of the estrogens adsorbed on the sludge. The variation of estrogens in a three-stage A/O system can be properly estimated and measured by a binary linear regression model with the variables of TP and TON (NO₂^--N and NO₃^--N), which is probably the important information for the improvement and optimization of wastewater treatment processes to obtain higher removal efficiency for estrogens.

Determination of two progestin metabolites (17α-hydroxypregnanolone and pregnanediol) and different classes of steroids (androgens, estrogens, corticosteroids, progestins) in rivers and wastewaters by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS)

A highly sensitive and robust method was developed for routine analysis of two progestin metabolites, 17α-hydroxypregnanolone (17OH-Δ5P) and pregnanediol (PD), and 31 other natural and synthetic steroids and related metabolites (estrogens, androgens, corticosteroids, progestins) in river water, as well as influents and effluents of municipal wastewater treatment plants (WWTP) using HPLC-MS/MS combined with solid-phase extraction. For the various matrixes considered, the optimized method showed satisfactory performance with recoveries of 70-120% for most of target steroids. The method detection limits (MDLs) ranged from 0.01 to 3ng/L for river water, 0.02 to 10ng/L for WWTP effluents, and 0.1 to 40ng/L for influents with good linearity and reproducibility. The developed method was successfully applied for the analysis of steroids in rivers and WWTP influent and effluents. WWTP influents concentrations of 17OH-Δ5P and PD were 51-256ng/L and up to 400ng/L, respectively, along with androstenedione (concentration range: 38-220ng/L), testosterone (11-26ng/L), estrone (2.3-37ng/L), 17β-estradiol (N.D.-8.7ng/L), 17α-hydroxyprogesterone (N.D.-66ng/L), medroxyprogesterone acetate (N.D.-5.3ng/L), and progesterone (2.0-22ng/L), while only androstenedione (ADD), estrone (E1), and estriol (E3) were detected in effluent with concentrations ranging up to 1.7ng/L, 0.90ng/L and 0.8ng/L, respectively. In river water samples, only ADD and E1 were detected with concentrations up to 1.0ng/L and 0.91ng/L. Our procedure represents the first method for analyzing 17OH-Δ5P and PD in environmental samples along with a large series of steroids.

An ultrahigh-performance chromatography/tandem mass spectrometry quantitative method for trace analysis of potential endocrine disrupting steroid hormones in estuarine sediments

RATIONALE

Estuaries are dynamic ecosystems, providing vital habitat for unique organisms of great ecological and commercial importance. The influx of natural and synthetic steroid hormones into estuaries poses risks to these organisms and to broader ecosystem health. However, detecting these trace level pollutants in estuarine water and sediment requires improved analytical techniques.

METHODS

We describe an optimized ultrahigh-performance chromatography/tandem mass spectrometry (UHPLC/MS/MS) method for simultaneous quantitation of four classes of steroid hormones (estrogens, glucocorticoids, androgens and progestins) in sediment samples collected from an Alabama estuary. Sediment samples were homogenized using Hydromatrix (HM) sorbent and extracted with methanol and water (70%, v/v). Centrifuged extracts were purified using an Agilent Bond Elut QuEChERS dispersive-SPE kit to eliminate interfering substances that could negatively influence the ionization process. Chromatographic separation was achieved on a Poroshell 120 Phenyl-Hexyl column using an Agilent 1290 Infinity II UHPLC pump. Quantitation was carried out using an Agilent triple quadrupole mass spectrometer equipped with a JetStream/ESI source in dual mode.

RESULTS

Chromatographic separation and better peak resolution were accomplished on an Agilent Poroshell 120 Phenyl-Hexyl column using a binary gradient method with a mobile phase consisting of 1 mM ammonium fluoride in water and a mixture of methanol/acetonitrile. A dynamic multiple reaction monitoring (MRM) method was developed by optimizing various MS parameters. The method was used to analyze target steroid hormones in estuarine sediments. A total of ten steroid hormones were detected at trace amounts in estuarine sediments.

CONCLUSIONS

The optimized analytical method described here involves reasonably simple sample preparation and simultaneous trace level quantitation of four classes (estrogens, glucocorticoids, androgens and progestins) of steroid hormones in a single experimental run. Copyright © 2016 John Wiley & Sons, Ltd.

Fate of new three anti-influenza drugs and one prodrug in the water environment

We evaluated the environmental fate of new three anti-influenza drugs, favipiravir (FAV), peramivir (PER), and laninamivir (LAN), and an active prodrug of LAN, laninamivir octanoate (LANO), in comparison with four conventional drugs, oseltamivir (OS), oseltamivir carboxylate (OC), amantadine (AMN), and zanamivir (ZAN) by photodegradation, biodegradation, and sorption to river sediments. In addition, we conducted 9-month survey of urban rivers in the Yodo River basin from 2015 to 2016 (including the influenza season) to investigate the current status of occurrence of these drugs in the river environment. The results clearly showed that FAV and LAN rapidly disappeared through photodegradation (half-lives 1 and 8 h, respectively), followed by LANO which gradually disappeared through biodegradation (half-life, 2 days). The remained PER and conventional drugs were, however, persistent and transported from upstream to downstream sites. Rates of their sorption to river sediments were negligibly small. Detected levels remained were in the range from N.D. to 89 ng/L for the river waters and from N.D. to 906 ng/L in sewage effluent. However, all of the remained drugs were effectively removed by ozonation after chlorination at a sewage treatment plant. These findings suggest the importance of introducing ozonation for reduction of pollution loads in rivers, helping to keep river environments safe. To the best of our knowledge, this is the first evaluation of the removal effects of natural sunlight, biodegradation, and sorption to river sediments on FAV, PER, LAN, LANO, and a conventional drug, AMN.

Parent and conjugated estrogens and progestagens in surface water of the Santa Ana River: Determination, occurrence, and risk assessment

The present study investigated the occurrence of 13 parent and conjugated estrogens and progestagens in surface water of the Santa Ana River. With the exception of the synthetic hormones 17α-ethynylestradiol and mestranol, other compounds were detected at least twice at 10 representative sites, with the ubiquitous estrone (E1) and 17β-estradiol-3-sulfate as the dominant compounds quantified (0.24-6.37 ng/L and 0.49-9.25 ng/L, respectively). Sites near dairy farms exhibited high levels of conjugates, whereas those close to a sewage treatment plant (STP) effluent outlet displayed relatively high concentrations of E1. Principle component analysis coupled with multiple linear regression revealed dairy farms and the STP as the 2 significant contamination sources, accounting for 69.9% and 31.1% of the total hormone burden, respectively. Risk assessment results suggested E1 and 17β-estradiol (E2) as the 2 hormones with the largest risks to aquatic organisms, and which combined, contributed >90% of the total estrogenicity. Most of the sites investigated showed that E1 and E2 posed a medium risk (0.1 < risk quotient < 1), whereas each induced a high risk (risk quotient >1) at sites severely impacted by the STP and dairy farms. These results suggest that river health would benefit from effective treatment of waste at the STP and dairy farms prior to discharge. Environ Toxicol Chem 2016;35:2657-2664. © 2016 SETAC.

Simultaneous determination of estrogens and progestogens in honey using high performance liquid chromatography-tandem mass spectrometry

This work describes the development and validation of a method for the simultaneous determination of 13 estrogens and progestogens in honey by high performance liquid chromatography-tandem mass spectrometry. The hormones were preconcentrated by solid phase extraction. Pretreatment variables were optimized for a better compatibility with electrospray ionization interfaced mass spectrometry. The analytes were analyzed in multiple-reaction monitoring mode with two pairs of precursor product ion transitions. The proposed method was validated with method detection limits of 0.01-0.33ng/g and good linearities (r²>0.9901) throughout the studied concentration range. The recoveries of analytes at the spiking levels (5ng/g and 25ng/g) ranged from 71.2% to 99.7%, with relative standard deviations below 20%. The method was used to determine the target compounds in honey samples (orange blossom, clover and multiflower) obtained from supermarkets. Two samples of honey were found to contain trace amounts of estrone (<MQL) or progesterone (0.2±0.1ng/g), respectively.

Metabolite profiling of sex developmental steroid conjugates reveals an association between decreased levels of steroid sulfates and adiposity in obese girls

Free and conjugated steroids coexist in a dynamic equilibrium due to complex biosynthetic and metabolic processes. This may have clinical significance related to various physiological conditions, including sex development involving the reproductive system. Therefore, we performed quantitative profiling of 16 serum steroids conjugated with glucuronic and sulfuric acids using liquid chromatography-mass spectrometry (LC-MS). All steroid conjugates were purified by solid-phase extraction and then separated through a 3-μm particle size C18 column (150mm×2.1mm) at a flow rate of 0.3 mL/min in the negative ionization mode. The LC-MS-based analysis was found to be linear (r(2)>0.99), and all steroid conjugates had a limit-of-quantification (LOQ) of 10ng/mL, except for cholesterol sulfate and 17β-estradiol-3,17-disulfate (20ng/mL). The extraction recoveries of all steroid conjugates ranged from 97.9% to 110.7%, while the overall precision (% CV) and accuracy (% bias) ranged from 4.8% to 10.9% and from 94.4% to 112.9% at four different concentrations, respectively. Profiling of steroid conjugates corrected by adiposity revealed decreased levels of steroid sulfates (P<0.01) in overweight and obese girls compared to normal girls. The suggested technique can be used for evaluating metabolic changes in steroid conjugates and for understanding the pathophysiology and relative contributions of adiposity in childhood obesity.

Detection of pharmaceuticals and phytochemicals together with their metabolites in hospital effluents in Japan, and their contribution to sewage treatment plant influents

The occurrence of 41 pharmaceuticals and phytochemicals (PPs) including their metabolites was surveyed in hospital effluent in an urban area of Japan. A detailed survey of sewage treatment plant (STP) influent and effluent, and river water was also conducted. Finally, mass balances with mass fluxes of the target PPs through the water flow were evaluated and the degree of contribution of hospital effluent to the environmental discharge was estimated. The results indicate that 38 compounds were detectable in hospital effluent over a wide concentration range from ng/L to μg/L, with a maximum of 92μg/L. The contributions of PPs in the hospital effluent to STP influent varied widely from <0.1% to 14.8%. Although almost all of the remaining components could be removed below 1.0ng/L at STPs by the addition of ozone treatment, a number of PPs still remained above 10ng/L in STP effluent. These findings suggest the importance of applying highly developed treatments to hospital effluents and at STPs in the future to reduce the environmental risks posed by PPs. To our knowledge, this is the first demonstration of the presence of two conjugated metabolites of acetaminophen, acetaminophen glucuronide and acetaminophen sulfate, as well as of loxoprofen and loxoprofen alcohol, in hospital effluent, STP, and river waters.

LC-MS/MS signal enhancement for estrogenic hormones in water samples using experimental design

Present paper describes the optimization of LC-MS/MS conditions by using experimental design for selective and sensitive determination of estrogenic hormones namely estradiol (E2), estrone (E1), estriol (E3) and ethinyl estradiol (EE2).

Determination of personal care products and hormones in leachate and groundwater from Polish MSW landfills by ultrasound-assisted emulsification microextraction and GC-MS

Determination of the endocrine disrupting compounds (EDCs) in leachate and groundwater samples from the landfill sites is very important because of the proven harmful effects of these compounds on human and animal organisms. A method combining ultrasound-assisted emulsification microextraction (USAEME) and gas chromatography-mass spectrometry (GC-MS) was developed for simultaneous determination of seven personal care products (PCPs): methylparaben (MP), ethylparaben (EP), propylparaben (PP), buthylparaben (BP), benzophenone (BPh), 3-(4-methylbenzylidene)camphor (4-MBC), N,N-diethyltoluamide (DEET), and two hormones: estrone (E1) and β-estradiol (E2) in landfill leachate and groundwater samples. The limit of detection (LOD)/limit of quantification (LOQ) values in landfill leachate and groundwater samples were in the range of 0.003-0.083/0.009-0.277 μg L(-1) and 0.001-0.015/0.002-0.049 μg L(-1), respectively. Quantitative recoveries and satisfactory precision were obtained. All studied compounds were found in the landfill leachates from Polish municipal solid waste (MSW) landfills; the concentrations were between 0.66 and 202.42 μg L(-1). The concentration of pollutants in groundwater samples was generally below 0.1 μg L(-1).

Occurrence and fate of selected anticancer, antimicrobial, and psychotropic pharmaceuticals in an urban river in a subcatchment of the Yodo River basin, Japan

Pollution status of six anticancer agents in the river water and effluents of sewage treatment plants (STPs) in Japan was surveyed with comparative analysis of the levels of four microbial and one psychotropic pharmaceuticals widely used for therapeutic medication. The area of survey is located in the Kanzaki-Ai River basin which is a major subcatchment of the Yodo River basin and is centered on a highly populated area that includes the middle and downstream reaches of the Yodo River. Selected cancer agents were bicalutamide, capecitabine, cyclophosphamide, doxifluridine, tamoxifen, and tegafur. A combination of strong anion solid-phase extraction cartridge under pH 11 for adsorption and optimization of liquid chromatography-tandem mass spectroscopy (LC-MS/MS) system was necessary to ensure high recovery rates (63-124% for river water and 52-115% for STP effluent). The year-round survey of these compounds in four seasons showed that all anticancer compounds were detected at median concentrations ranged from not detected to 32 ng/L in the river water and from not detected to 245 ng/L in the effluents of sewage treatment plants not using ozonation. In the case of bicalutamide (an active antiandrogen used to treat prostate cancer), the maximum concentration detected was 254 ng/L in river water and 1032 ng/L in non-ozonated sewage treatment plant effluents. Based on the mass balance, sewage treatment plants were the primary sources of anticancer compounds as well as the other pharmaceuticals in the river, and the attenuation effect of the river water was small. Ozonation at sewage treatment plants was effective in removing these compounds. To the best of our knowledge, this study is the first to report the existence of bicalutamide, doxifluridine, and tegafur in the river environment.

Evaluation of concentrations of pharmaceuticals detected in sewage influents in Japan by using annual shipping and sales data

A year-round monitoring survey of sewage flowing into sewage treatment plants located in urban Japan was conducted by targeting seven representative pharmaceutical components-atenolol (ATL), ciprofloxacin (CFX), clarithromycin (CTM), diclofenac (DCF), diltiazem (DTZ), disopyramide (DSP), and sulpiride (SPR)-detected in the river environment. For each of these components, two types of predicted concentration were estimated on the basis of two types of data (the shipping volume and sales volume of each component). The measured concentration of each component obtained through the survey and the two types of estimated predicted concentration of each component were then compared. The correspondence ratio between the predicted concentration estimated from the shipping volume of the component and the measured concentration (predicted concentration/measured concentration) was, for ATL, 3.1; CFX, 1.4; CTM, 1.4; DCF, 0.2; DTZ, 0.9; DSP, 11.6; and SPR, 1.1. The correspondence ratio between the predicted concentration estimated from the sales volume of the component and the measured concentration was, for ATL, 0.5; CFX, 1.1; CTM, 0.8; DCF, 0.1; DTZ, 0.2; DSP, 0.7; and SPR, 0.8. Although a generally corresponding trend was seen regardless of whether the prediction was based on shipping volume or sales volume, the predicted concentrations estimated from the shipping volumes of all components expect DSP were found, to our knowledge for the first time in Japan, to correspond better than those based on sales volumes to the measured concentrations. These findings should help to improve the prediction accuracy of concentrations of pharmaceutical components in river waters.

Simultaneous detection of endocrine disrupting chemicals including conjugates in municipal wastewater and sludge with enhanced sample pretreatment and UPLC-MS/MS

The co-existence of free and conjugated estrogens and the interference from complex matrices often lead to largely variable detected concentrations and sometimes even negative removal efficiencies of typical endocrine disrupting chemicals (EDCs) in wastewater treatment plants (WWTPs). In this study, a highly selective and sensitive method was developed for simultaneous extraction, elution, and detection of 12 EDCs (i.e., 4 free estrogens, 6 conjugated estrogens, and 2 phenolic compounds) in municipal wastewater and sludge. Sample pretreatment and ultra-performance liquid chromatography-tandem mass spectrometry detection were optimized to improve the detection selectivity and sensitivity. The results indicate that the additional purification process was highly effective in reducing the matrix interference, and the limits of quantification reached as low as 0.04-2.2 ng L(-1) in wastewater and 0.05-4.9 ng g(-1) in sludge for all target EDCs. The developed method was successfully applied to explore the behavior of target EDCs in a local WWTP. The conjugates occupied a considerable portion (4.3-76.9% in molar ratio) of each related estrogen in the influent. Most of the target EDCs could not be completely removed in WWTPs, thus posing a potential threat to aquatic ecosystems.

Detection of peramivir and laninamivir, new anti-influenza drugs, in sewage effluent and river waters in Japan

This is the first report of the detection of two new anti-influenza drugs, peramivir (PER) and laninamivir (LAN), in Japanese sewage effluent and river waters. Over about 1 year from October 2013 to July 2014, including the influenza prevalence season in January and February 2014, we monitored for five anti-influenza drugs—oseltamivir (OS), oseltamivir carboxylate (OC), zanamivir (ZAN), PER, and LAN—in river waters and in sewage effluent flowing into urban rivers of the Yodo River system in Japan. The dynamic profiles of these anti-influenza drugs were synchronized well with that of the numbers of influenza patients treated with the drugs. The highest levels in sewage effluents and river waters were, respectively, 82 and 41 ng/L (OS), 347 and 125 ng/L (OC), 110 and 35 ng/L (ZAN), 64 and 11 ng/L (PER), and 21 and 9 ng/L (LAN). However, application of ozone treatment before discharge from sewage treatment plants was effective in reducing the levels of these anti-influenza drugs in effluent. The effectiveness of the ozone treatment and the drug dependent difference in susceptibility against ozone were further evidenced by ozonation of a STP effluent in a batch reactor. These findings should help to promote further environmental risk assessment of the generation of drug-resistant influenza viruses in aquatic environments.

Evaluation of Estrogenic Activity of Wastewater: Comparison Among In Vitro ERα Reporter Gene Assay, In Vivo Vitellogenin Induction, and Chemical Analysis

The in vitro estrogen receptor (ER) reporter gene assay has long been used to measure estrogenic activity in wastewater. In a previous study, we demonstrated that the assay represents net estrogenic activity in the balance between estrogenic and antiestrogenic activities in wastewater. However, it remained unclear whether the net estrogenic activity measured by the in vitro ERα reporter gene assay can predict the in vivo estrogenic effect of wastewater. To determine this, we measured the following: estrogenic and antiestrogenic activities of wastewater and reclaimed water by the in vitro ERα reporter gene assay, expression of vitellogenin-1 (vtg1) and choriogenin-H (chgH) in male medaka (Oryzias latipes) by quantitative real-time PCR, and estrone, 17β-estradiol, estriol, and 17α-ethynylestradiol concentrations chemically to predict estrogenic activity. The net estrogenic activity measured by the in vitro medaka ERα reporter gene assay predicted the in vivo vtg1/chgH expression in male medaka more accurately than the concentrations of estrogens. These results also mean that in vivo vtg1/chgH expression in male medaka is determined by the balance between estrogenic and antiestrogenic activities. The in vitro medaka ERα reporter gene assay also predicted in vivo vtg1/chgH expression on male medaka better than the human ERα reporter gene assay.

Removal of natural estrogens and their conjugates in municipal wastewater treatment plants: a critical review

This article reviews studies focusing on the removal performance of natural estrogens in municipal wastewater treatment plants (WWTPs). Key factors influencing removal include: sludge retention time (SRT), aeration, temperature, mixed liquor suspended solids (MLSS), and substrate concentration. Batch studies show that natural estrogens should biodegrade well; however, batch observations do not always agree with observations from full-scale municipal WWTPs. To explain this discrepancy, deconjugation kinetics of estrogen conjugates in lab-scale studies were examined and compared. Most estrogen conjugates with slow deconjugation rates are unlikely to be easily removed; others could be cleaved in WWTP settings. Nevertheless, some estrogens cleaved from their conjugates may be found in treated effluent, because deconjugation requires several hours or longer, and there is insufficient rest time for the biodegradation of the cleaved natural estrogens in the WWTP. Therefore, WWTP removals of natural estrogens are likely to be underestimated when estrogen conjugates are present in raw wastewater. This review suggests that biodeconjugation of estrogen conjugates should be enhanced to more effectively remove natural estrogens in WWTPs.

Matrix effect during the membrane-assisted solvent extraction coupled to liquid chromatography tandem mass spectrometry for the determination of a variety of endocrine disrupting compounds in wastewater

Membrane-assisted solvent extraction (MASE) coupled to liquid chromatography-triple quadrupole mass spectrometry (LC-MS/MS) was studied for the determination of a variety of emerging and priority compounds in wastewater. Among the target analytes studied certain hormones (estrone (E1), 17β-estradiol (E2), androsterone (ADT), 17α-ethynyl estradiol (EE2), diethylstilbestrol (DES), equilin (EQ), testosterone (TT), mestranol (MeEE2), 19-norethisterone (NT), progesterone (PG) and equilenin (EQN)), alkylphenols (APs) (4-tert-octylphenol (4tOP), nonylphenol technical mixture (NPs) and 4n-octylphenol (4nOP)) and BPA were included. The work was primarily focused in the LC-MS/MS detection step, both in terms of variable optimization and with respect to the matrix effect study. Both, electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) were assessed both in the negative and positive mode, including the optimization of MS/MS operating conditions. The best results were obtained, in most of the cases, for ESI using 0.05% ammonium hydroxide as buffer solution in the mobile phase, composed with methanol and water. Under optimum detection conditions, matrix effect during the detection step was thoroughly studied. Dilution, correction with deuterated analogues and clean-up of the extracts were evaluated for matrix effect correction. Clean-up with Florisil together with correction with deuterated analogues provided the most satisfactory results, with apparent recoveries in the 57-136% range and method detection limits in the low ngL(-1) level for most of the analytes. For further validation of the method, two separated extraction procedures, the above mentioned MASE, and conventional solid phase extraction (SPE) were compared during the analysis of real samples and comparable results were successfully obtained for E1, E2, EE2, DES, NT, TT, EQ, PG, BPA, ADT, 4nOP, 4tOP, NPs and EQN.

Co-occurrence of estrogenic and antiestrogenic activities in wastewater: quantitative evaluation of balance by in vitro ERα reporter gene assay and chemical analysis

Endocrine-disrupting chemicals are exogenous substances that alter the function of the endocrine system, with adverse health effects on organisms or their progeny. In vitro estrogen receptor (ER) reporter gene assays have long been used to measure estrogenic activity in wastewater. Nevertheless, there is still uncertainty about their usefulness in environmental monitoring on account of a discrepancy between the estrogenic response of the in vitro assay and concentrations of estrogenic compounds determined by chemical analysis. Here, we measured estrogenic and antiestrogenic activities in wastewater by ERα reporter gene assay. All samples were simultaneously analyzed for estrone, 17β-estradiol, estriol, and 17α-ethynylestradiol, and the concentrations were used to predict estrogenic activity. All samples in which measured estrogenic activity was significantly lower than predicted showed strong antiestrogenic activity. In addition, we confirmed that the fraction that did not have antiestrogenic activity showed stronger estrogenic activity than the unfractionated wastewater extract. These results indicate that antiestrogenic compounds in wastewater suppress the activity of natural estrogens, and the reporter gene assay represents the net activity.

Mass balance of anti-influenza drugs discharged into the Yodo River system, Japan, under an influenza outbreak

In February 2011, at the peak of an influenza outbreak, we performed a comprehensive analysis of the mass balances of four anti-influenza drugs-oseltamivir (OS), oseltamivir carboxylate (OC), amantadine (AMN), and zanamivir (ZAN)-in the urban area of the Yodo River system. This area includes three main river catchments (the Katsura, Uji, and Kidzu Rivers) and is home to 12 million people, about 10% of Japan's population. Water was sampled at six main rivers and 13 tributary sites and eight sewage treatment plants (STPs). We concluded that the STP effluents were the major sources of the anti-influenza drug load in the Yodo River system (68-94% of total mass fluxes). Extended measurement throughout the Yodo River system further showed only small fluctuations of the ratio of OS to OC from 0.2 to 0.3, suggesting that OS and its metabolite are environmentally stable. The results also clearly showed the importance of reducing the levels of anti-influenza drugs in the water environment by reducing their emission at STPs.

Assessment of in vivo estrogenic response and identification of environmental estrogens in influent and effluent from a sewage treatment plant

The in vivo estrogenic response and estrogenic contents of the influent and effluent collected from a sewage treatment plant located in Jiaozuo were assessed. The bioassay showed significant serum vitellogenin (VTG) induction in all the treated male goldfish (Carassius auratus) and significant gonad atrophies were only observed in the fish induced the most VTG expressions. Six target estrogens (estrone, 17β-estradiol, 17α-ethynylestradiol, 4-n-octylphenol, 4-n-nonylphenol and bisphenol A) were detected in different polar fractions, with the exception of the 25 % and 50 % methanol fractions extracted from the influent and the 25 %, 50 %, 95 % and 100 % methanol fractions extracted from the effluent. For both the influent and effluent, natural and synthetic steroidal estrogens were detected in those extracted fractions induced the most abundant VTG expressions.