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Andrew C Johnson - One of the best experts on this subject based on the ideXlab platform.
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determination of cyclophosphamide and ifosfamide in Sewage Effluent by stable isotope dilution liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2011Co-Authors: Neville R Llewellyn, P Lloyd, Monika D Jurgens, Andrew C JohnsonAbstract:A reliable and specific method was developed for the determination of the cytotoxic drugs cyclophosphamide and ifosfamide in Sewage Effluent. The most successful combination was found to be Strata-X solid-phase extraction followed by Florisil® clean-up with analysis by liquid chromatography–tandem mass spectrometry. Quantification by internal standardisation was achieved using custom synthesised d4-cyclophophosphamide. The mass spectrometer was operated in highly selective reaction monitoring (HSRM) mode, which significantly reduced matrix noise and improved sensitivity. Although it suffered from some ionisation suppression, electrospray ionisation (ESI) was found to give an order of magnitude better sensitivity in terms of limit of detection than atmospheric pressure chemical ionisation (APCI). Using final Effluent from two different Sewage treatment plants, the method was validated following official European guidelines and shown to be a high performance tool for routine analysis at the sub-nanogram per litre level. Depending on the matrix, the limit of detection for cyclophosphamide was between 0.03 ng/L and 0.12 ng/L and for ifosfamide between 0.05 ng/L and 0.09 ng/L. For cyclophosphamide the accuracy and precision, tested at 1.7 ng/L, were 98–109% and ≤13%, CV respectively. For ifosfamide the accuracy and precision, tested at 1.1 ng/L, were 98–113% and ≤15% CV, respectively. Depending on the sample matrix the absolute recovery of the internal standard was between 57% and 70%. The method was tested by analysis of spot samples taken from the final Effluent discharges of two Sewage treatment plants; the first using a conventional trickling filter treatment process and second employing activated sludge followed by ultra violet treatment. Cyclophosphamide was detected at 0.19 ng/L at the first plant and at the second detected at 3.7 ng/L and 3.5 ng/L, before and after the UV treatment process; ifosfamide was not detectable at either plant.
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rapid determination of free and conjugated estrogen in different water matrices by liquid chromatography tandem mass spectrometry
Chemosphere, 2009Co-Authors: Vimal Kumar, Naoyuki Yamashita, Norihide Nakada, Makoto Yasojima, Andrew C Johnson, Hiroaki TanakaAbstract:Abstract This article describes the development of a short pre-treatment method that allows the simultaneous analysis of free estrogens (estrone, 17β-estradiol, estriol and 17α-ethynylestradiol) and their sulphate and glucuronide conjugated forms. For a range of matrices, from Sewage Effluent to river water, the developed methodology based on solid-phase extraction and fractionation technique with ultra-performance liquid chromatography system showed effective separation of the targeted estrogens. The detection limits of this method ranged from 0.2 to 0.8 ng L −1 for river water. The recoveries for river water and Sewage Effluent varied from 63% to 127%. The problems of matrix effects and ion suppression or enhancement were allowed quantitatively for in the analysis using standard addition. The developed method was used successfully to detect estrogens and their conjugates in both raw and treated wastewater, and river water at a location in Japan. High concentrations of the free estrogens estrone, 17β-estradiol and estriol were found in the influent (22.6, 77.2, 64.6 ng L −1 , respectively) but only E1 was still present at a high concentration in the Effluent which was reflected in the downstream river concentration. Estrone-3-sulphate was detected up to 18.0 ng L −1 in influent water sample and 1.1 ng L −1 in downstream water. For the sulphate conjugates, removal efficiencies varied from 35 to 88%. Glucuronide conjugates were detected only once in the Sewage influent.
Ravi Naidu - One of the best experts on this subject based on the ideXlab platform.
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effects of secondary treated Sewage Effluent application on the populations of microfauna in a hardwood plantation soil bolivar hiat trial
Geoderma, 1998Co-Authors: V V S R Gupta, S Rogers, Ravi NaiduAbstract:Abstract In this study we measured the effects of using of secondary treated Sewage Effluent for irrigation (3.5 y) of a hardwood plantation ( Eucalyptus or Casuarina ) on the abundance and species composition of protozoa and nematodes in soil. Measurable populations of protozoa and free-living nematodes were observed in all treatments. Application of secondary treated Sewage Effluent had a stimulatory effect on the abundance of total and active protozoa and altered the species composition of all groups of protozoa and nematodes. In general populations were higher in soils under dripper lines than between dripper lines. Populations of protozoa were highest under Eucalyptus receiving Sewage Effluent and the difference between `under dripper line' and `between dripper line' was maximum in Casuarina plantation. A number of protozoan species belonging to genera Acanthamoeba (group 3 species such as A. castellanii ) and Naegleria (i.e. potentially pathogenic protozoa) were observed in plots irrigated with secondary treated Sewage Effluent. Large (>50 μm) amoebae and ciliate species were mainly observed in soils receiving Sewage Effluent. Bacterial feeding nematodes were the dominant group of free-living nematodes in all soils, and Effluent irrigation increased their percentage especially in soil under dripper lines. Overall results in this study suggest that where heavy metal contamination is minimal, irrigation with secondary treated Sewage Effluent does not have significant negative effects on the abundance of protozoa and nematodes. Significant increases in the abundance of active protozoa and changes in species composition of protozoa and nematodes suggest an increased microbial turnover in Effluent treated soils.
Hiroaki Tanaka - One of the best experts on this subject based on the ideXlab platform.
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detection of peramivir and laninamivir new anti influenza drugs in Sewage Effluent and river waters in japan
PLOS ONE, 2015Co-Authors: Takashi Azuma, Hirotaka Ishiuchi, Tomomi Inoyama, Yusuke Teranishi, Misato Yamaoka, Takaji Sato, Naoyuki Yamashita, Hiroaki Tanaka, Yoshiki MinoAbstract: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.
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rapid determination of free and conjugated estrogen in different water matrices by liquid chromatography tandem mass spectrometry
Chemosphere, 2009Co-Authors: Vimal Kumar, Naoyuki Yamashita, Norihide Nakada, Makoto Yasojima, Andrew C Johnson, Hiroaki TanakaAbstract:Abstract This article describes the development of a short pre-treatment method that allows the simultaneous analysis of free estrogens (estrone, 17β-estradiol, estriol and 17α-ethynylestradiol) and their sulphate and glucuronide conjugated forms. For a range of matrices, from Sewage Effluent to river water, the developed methodology based on solid-phase extraction and fractionation technique with ultra-performance liquid chromatography system showed effective separation of the targeted estrogens. The detection limits of this method ranged from 0.2 to 0.8 ng L −1 for river water. The recoveries for river water and Sewage Effluent varied from 63% to 127%. The problems of matrix effects and ion suppression or enhancement were allowed quantitatively for in the analysis using standard addition. The developed method was used successfully to detect estrogens and their conjugates in both raw and treated wastewater, and river water at a location in Japan. High concentrations of the free estrogens estrone, 17β-estradiol and estriol were found in the influent (22.6, 77.2, 64.6 ng L −1 , respectively) but only E1 was still present at a high concentration in the Effluent which was reflected in the downstream river concentration. Estrone-3-sulphate was detected up to 18.0 ng L −1 in influent water sample and 1.1 ng L −1 in downstream water. For the sulphate conjugates, removal efficiencies varied from 35 to 88%. Glucuronide conjugates were detected only once in the Sewage influent.
Steven P Carroll - One of the best experts on this subject based on the ideXlab platform.
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use of chemometrics methods and multicriteria decision making for site selection for sustainable on site Sewage Effluent disposal
Analytica Chimica Acta, 2004Co-Authors: Wael Alshiekh Khalil, Ashantha Goonetilleke, Serge Kokot, Steven P CarrollAbstract:Abstract This paper presents a study undertaken to evaluate site suitability for Sewage Effluent renovation based on physico-chemical characteristics of the soil. The results obtained showed that as the soil becomes acidic, the phosphorus concentration in the soil reduces accordingly. The chloride ion concentration was found to be a reliable indicator for evaluating the soil capacity to remove nitrogen. A high cation exchange capacity (CEC) can enhance the renovation of Sewage Effluent. Soils with high quartz content had a low CEC with high organic matter content (OM) being able to compensate. Therefore, an understanding of the micro-nutrients in the soil, organic matter content and chloride ion concentration are important. To facilitate a multi-variate approach for site selection, multicriteria decision-making (MCDM) methods, PROMETHEE and GAIA, were applied for analysis of a sequence of three matrices consisting of 8, 16, and 48 soil site objects, respectively, and seven soil property parameters. Matrix models and the interpretation of results are discussed in detail. From these analyses, PROMETHEE II net outranking flows, ϕ , found that two sites were always among the top three ranks of the three matrix models, which suggested that they were the most suitable for Sewage Effluent renovation. The criteria CEC and OM, were particularly important for the selection of these better sites, but pH and Cl − attributes discriminated the weaker performing sites from the better ones; as well the PO 4 3− and the NH 3 –N criteria were in general opposition to CEC, OM, pH and Cl − but were much less effective as discriminators. Consideration of net outranking flows suggested an approach method for the selection of other possibly suitable sites for Sewage Effluent renovation.
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use of chemometrics methods and multicriteria decision making for site selection for sustainable on site Sewage Effluent disposal
Faculty of Built Environment and Engineering, 2004Co-Authors: Wael Alshiekh Khalil, Ashantha Goonetilleke, Serge Kokot, Steven P CarrollAbstract:This paper presents a study undertaken to evaluate site suitability for Sewage Effluent renovation based on physico-chemical characteristics of the soil. The results obtained showed that as the soil becomes acidic, the phosphorus concentration in the soil reduces accordingly. The chloride ion concentration was found to be a reliable indicator for evaluating the soil capacity to remove nitrogen. A high cation exchange capacity (CEC) can enhance the renovation of Sewage Effluent. Soils with high quartz content had a low CEC with high organic matter content (OM) being able to compensate. Therefore, an understanding of the micro-nutrients in the soil, organic matter content and chloride ion concentration are important. To facilitate a multi-variate approach for site selection, multicriteria decision-making methods (MCDM) methods, PROMETHEE and GAIA, were applied for analysis of a sequence of three matrices consisting of 8, 16, and 48 soil site objects respectively, and seven soil property parameters. Matrix models and the interpretation of results are discussed in detail. From these analyses, PROMETHEE II net outranking flows,￪, found that two sites were always among the top three ranks of the three matrix models, which suggested that they were the most suitable for Sewage Effluent renovation. The criteria CEC and OM, were particularly important for the selection of these better sites, but pH and Cl- attributes discriminated the weaker performing sites from the better ones; as well the PO43- and the NH3-N criteria were in general opposition to CEC, OM, pH and Cl- but were much less effective as discriminators. Consideration of net outranking flows suggested an approach method for the selection of other possibly suitable sites for Sewage Effluent renovation.
Lan Ding - One of the best experts on this subject based on the ideXlab platform.
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determination of fluoroquinolone antibiotics in environmental water samples based on magnetic molecularly imprinted polymer extraction followed by liquid chromatography tandem mass spectrometry
Analytica Chimica Acta, 2010Co-Authors: Ligang Chen, Xiaopan Zhang, Xin Sun, Lei Sun, Hui Wang, Qi Zhao, Hanqi Zhang, Lan DingAbstract:Abstract A simple method based on magnetic separation for selective extraction of fluoroquinolones (FQs) from environmental water samples has been developed using magnetic molecularly imprinted polymer (MMIP) as sorbent. The MMIP has been prepared using ciprofloxacin as template molecule, methacrylic acid as functional monomer, ethylene glycol dimethacrylate as cross-linking agent and Fe 3 O 4 magnetite as magnetic component. The polymer has been characterized by scanning electron microscopy, Fourier-transform infrared spectrometry and vibrating sample magnetometry. Various parameters affecting the extraction efficiency were evaluated in order to achieve optimal concentration and reduce non-specific interactions. The analytes desorbed from the polymers were determined by liquid chromatography–tandem mass spectrometry. The matrix effect was evaluated by using different washing solvents for removing interfering compounds from the MMIPs after sample loading. Under the optimal conditions, the linearity of the method obtained is in the range of 20–2000 ng L −1 . The detection limits of FQs are in the range of 3.2–6.2 ng L −1 . The relative standard deviations of intra- and inter-day tests ranging from 2.5 to 7.2% and from 3.6 to 9.1% are obtained. In all three spiked levels (20, 100 and 200 ng L −1 ), the recoveries of FQs are in the range of 76.3–94.2%. The proposed method was successfully applied to determine FQs including ciprofloxacin, enrofloxacin, lomefloxacin, levofloxacin, fleroxacin and sparfloxacin in different water samples, such as lake water, river water, primary and final Sewage Effluent. Ciprofloxacin and fleroxacin were found in primary and final Sewage Effluent samples with the contents in the range of 26–87 ng L −1 .