Rapid analysis of iodinated X-ray contrast media in secondary and tertiary treated wastewater by direct injection liquid chromatography-tandem mass spectrometry

The iodinated X-ray contrast media are the most widely administered intravascular pharmaceuticals and are known to persist in the aquatic environment. A rapid method using direct injection liquid chromatography-tandem mass spectrometry (DI-LC-MS/MS) has been developed to measure eight ICM. These include iopamidol, iothalamic acid, diatrizoic acid, iohexol, iomeprol, iopromide, plus both ioxaglic acid and iodipamide, which have not previously reported in the literature. The LC-MS/MS fragmentation patterns obtained for each of the compounds are discussed and the fragments lost for each transition are identified. Matrix effects in post-RO water, MQ water, tap water and secondary effluent have also been investigated. The DI-LC-MS/MS method was validated on both secondary and tertiary treated wastewater, and applied to samples from an advanced activated sludge wastewater treatment plant (WWTP) and a water recycling facility using microfiltration (MF) and reverse osmosis (RO) in Perth, Western Australia. As well as providing information of the efficacy for RO to remove specific ICM, these results also represent the first values of ICM published in the literature for Australia.     

Occurrence of pharmaceutical metabolites and transformation products in the aquatic environment of the Mediterranean area

The presence of pharmaceutically active substances (PhACs) in aquatic ecosystems is of great concern due to their constant occurrence in different water systems and potential negative effects on the quality of water and living organisms. After consumption, PhACs are excreted as the parent compound, and/or as free or conjugated metabolites, which might finally arrive to surface and ground waters after their incomplete removal (and possible degradation) in the wastewater treatment plants (WWTP). A large amount of data about parent PhACs in water has been reported in the literature in the last decade; however, there is a lack of information about the presence of their metabolites and transformation/degradation products (TPs). Recent publications report that PhACs found in water are only the “top of the iceberg” in relation to the environmental impact associated to the consumption of PhACs. From a scientific-technological point of view, the overall study of PhACs is a challenge and requires to advance with respect to current knowledge and analytical capacities, considering several key aspects, such as the reliable identification and quantification of the compounds, the improvement of the removal efficiency by the WWTPs, the study of their behaviour in the environment (e.g. persistence and biodegradability), and the environmental risk assessment, considering not only the parent PhACs but also their transformation/metabolism products. In this work, it is intended to delve into this problem, presenting a detailed overview on metabolites and TPs of PhACs in environmental waters from the Mediterranean area. Analytical and environmental problems associated to the determination of these compounds are briefly commented, ending the paper with the main conclusions and expected future trends in relation to this field.     

Determination of phenylurea herbicides in natural waters at concentrations below 1 ng l using solid-phase extraction, derivatization, and solid-phase microextraction–gas chromatography–mass spectrometry

A procedure is presented which allows the ultratrace level determination of phenylurea herbicides (PUHs) in natural waters. Samples were enriched by solid-phase extraction (SPE) on Carbopack B and alkylated with iodoethane and sodium hydride to yield thermostable products. After derivatization, the aqueous samples were extracted and injected by SPME. The use of iodoethane instead of iodomethane allowed the differentiation between parent compounds and the N-demethylated metabolites. Limits of detection were between 0.3 and 1.0 ng/l for the parent compounds. Standard deviations below 10% were achieved for samples containing more than 4 ng/l in very different matrices including Nanopure water, lake water, and waste water treatment plant (WWTP) effluent. Moreover, the para-hydroxylated metabolite of diuron could be quantified with the same procedure. The presence of further metabolites was assessed qualitatively. Chromatography was stable over a large number of measurements even with dirty samples from WWTP effluent. The precision and sensitivity of the developed analytical method allowed the investigation of the fate of PUHs in lakes, their degradation during drinking water treatment and their transport within the North Sea.     

Dynamic simulations of waste water treatment plant operation

Activated Sludge Model No. 1 (ASM1) was used to model the biological stage of an actual waste water treatment plant (WWTP). Some possibilities for the utilisation of simulation programs for WWTP operation are presented. Simulation calculations were performed taking the conditions of WWTP in Nové Zámky, the Slovak Republic, into consideration, where measurements of the diurnal variations in waste water flow and composition at the inlet and outlet were carried out. A calibrated model predicting the influence of changes in the waste water composition and the operational parameters on the effluent waste water quality and related operational costs is available. Values of the operational parameters (solids retention time, internal recirculation flow, dissolved oxygen concentration) for effective operation (effluent concentration values, oxygen consumption, charges, i.e. charges for waste water discharge into the recipient water body) of the WWTP were obtained by simulations. The presented results are for illustration purposes only and are not intended as instructions for the operation of a waste water treatment plant. They correspond to the calibrated mathematical model ASM 1 based on the results of experimental measurements and operational data, as well as on the technical and monitoring level of the WWTP.     

Development of a stir bar sorptive extraction and thermal desorption-gas chromatography-mass spectrometry method for determining synthetic musks in water samples

This study presents the development of an analytical method for determining 9 synthetic musks in water matrices. The developed method is based on stir bar sorptive extraction (SBSE), coated with polydimethylsiloxane, and coupled with a thermal desorption–gas chromatography–mass spectrometry system (TD–GC–MS). SBSE can efficiently trap and desorb the analytes providing low limits of detection (between 0.02 ng L⁻¹ and 0.3 ng L⁻¹). Method validation showed good linearity, repeatability and reproducibility for all compounds. Furthermore, the limited manipulation of the sample required in this method implies a significant decrease of the risk of external contamination of the samples. The performance of the method in real samples was evaluated by analysing biological wastewater treatment plant (WWTP) influent and effluent samples, reverse osmosis treatment plant effluents and river waters. The most abundant musk was galaxolide with values up to 2069 ng L⁻¹ and 1432 ng L⁻¹ in the influent and effluent of urban WWTP samples, respectively. Cashmeran, Pantolide and Tonalide were also detected in all the matrices with values up to 94 ng L⁻¹, 26 ng L⁻¹ and 88 ng L⁻¹, respectively. Although in Europe the use of nitromusks in cosmetics is prohibited, musk xylene and musk ketone were detected both in the WWTP and in the river samples. As far as we know, this is the first time than a SBSE method coupled with TD is applied for the determination of synthetic musks in water samples.     

Simultaneous extraction and analysis of 11 tetracycline and sulfonamide antibiotics in influent and effluent domestic wastewater by solid-phase extraction and liquid chromatography-electrospray ionization tandem mass spectrometry

Wastewater treatment plants (WWTPs) in which antibiotic compounds are not totally eliminated are considered to be point sources of antibiotic contamination in surface and ground waters. Therefore, there is a need for sensitive and reliable analytical methods for measuring these compounds in WWTP water matrices. This paper describes a simultaneous method for the determination of six tetracyclines (TCs) (oxytetracycline (OTC), tetracycline (TC), demeclocycline (DMC), chlortetracycline (CTC), doxycycline (DXC), meclocycline (MCC)) and five sulfonamides (SAs) (sulfathiazole (STZ), sulfamethazine (SMT), sulfachloropyridazine (SCP), sulfamethoxazole (SMX) and sulfadimethoxine (SDM)) using solid-phase extraction followed by liquid chromatography-ion trap tandem mass spectrometry. The average recovery of 11 antibiotics for simultaneous extraction was 83.3+/-12.6 and 89.8+/-11.5% for six TCs, and 95.2+/-11.4 and 97.7+/-10.6% for five SAs in the influent and effluent water, respectively. Matrix effects were found to be significant when measuring TCs but not SAs. The accuracy and day-to-day variation of the method fell within an acceptable range of 15% absolute. Method detection limits in wastewater matrices were between 0.03 and 0.07 microg/L. For the investigated 11 antibiotic compounds TC, DMC, CTC, DXC, SMT, SMX and SDM were found in the influents with a concentration range of 0.05-1.09 microg/L. CTC, DXC and SMX were also detected in the effluents with a concentration range of 0.06-0.21 microg/L. These results were compared with those in WWTP effluents of Canada, Germany and Switzerland.     

Analysis of 32 priority substances from EU water framework directive in wastewaters,surface and drinking waters with a fast sample treatment methodology

A simple, fast, and sensitive method is proposed for the analysis of 32 priority substances (PS) from EU Water Framework Directive (WFD) and the first Watch List in effluents of wastewater treatment plants (EWW), surface waters (SW) and drinking waters (DW). Dispersive liquid-liquid microextraction (DLLME) and gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) is used. For DLLME, a mixture of 1,1,2-trichloroethane as extraction solvent (75 µL) and acetonitrile as disperser solvent (3.2 mL) is proposed. The method was validated in EWW, SW and DW, showing satisfactory accuracy values ranging from 90% to 104%, good precision (relative standard deviation, RSD%, lower than 13%) and uncertainty values between 7% and 34%. Regarding sensitivity, method limits of quantification (MLOQs) of 4.8, 5.2 and 8.8 ng L^?1 for DW, SW and EWW, respectively, were obtained. The developed method was applied to analyze PS in water from effluents of waste water treatment plants (WWTPs), surface water of the Llobregat River and its main tributaries (Catalonia, NE Spain) and drinking water from a Drinking Water Treatment Plant (DWTP). Moreover, the efficiency of treatment plants (DWTP, WWTP) on the elimination of PS was evaluated. Only 3 PS (lindane, terbutryn and dicofol) were detected, being terbutryn the compound found at the highest levels (up to 493 ng L^?1 in EWW samples). Regarding environmental quality standard (WFD) for terbutryn in surface waters, only one sample, the Rubí stream (431 ng L^?1), showed levels of terbutryn higher than maximum allowable concentration (340 ng L^?1).     

Analytical methodologies for the determination of nitroimidazole residues in biological and environmental liquid samples: A review

Nitroimidazoles (NDZs) are antiprotozoal drugs that are typically used in veterinary and human medicine. NDZs and their metabolites are believed to possess genotoxic, carcinogenic and mutagenic properties, and this is (one reason) why their use has been banned within the European Union. Hence, the determination of trace residues of these substances in edible animal tissues has been of growing concern over the past few years. Even, though there has been a need to develop sensitive and reliable analytical methods to study the residues of these compounds in different matrices, available methodologies in environmental samples are rather limited. These and other pharmaceutical compounds have become one of the most important new classes of environmental pollutants that have been detected in wastewater-treatment-plant (WWTP) effluents, receiving waters, drinking water and groundwater. A compilation of the most representative analytical methodologies for the determination of NDZ residues during the last decade is presented in this paper. Its scope is the two main areas which require their determination, namely biological and environmental matrices. A detailed explanation of both areas, including sample treatment and detection systems, and future trends is presented, focusing on the difficulties of confirming analytes at low concentration levels.     

Solid-phase extraction-high-performance liquid chromatography-ion trap mass spectrometry for analysis of trace concentrations of macrolide antibiotics in natural and waste water matrices

A method using solid-phase extraction (SPE) combined with high-performance liquid chromatography-ion trap tandem mass spectrometry (LC-MS-MS) has been developed for determination of trace concentrations of erythromycin-H2O (ETM-H2O), roxithromycin (RTM) and tylosin (TLS) in natural and waste water matrices. These macrolides (MLs) were extracted from water samples using Oasis HLB cartridges, and the average recovery was 93.6 +/- 8.6, 92.1 +/- 10.0, and 94.3 +/- 8.9% for ETM-H2O, RTM and TLS in surface water, respectively. For water from the influent of a wastewater treatment plant (WWTP), the average recovery was 84.8 +/- 14.0, 83.2 +/- 13.1, and 86.1 +/- 13.4% for ETM-H2O, RTM and TLS, respectively. Method detection limits in a natural water matrices were 0.07, 0.03, and 0.05 microg/l for ETM-H2O, RTM, and TLS, respectively. Fragment or product ions from MS spectra using in-source collision-induced dissociation and MS-MS spectra have been identified. The accuracy and day-to-day variation of the method fell within acceptable ranges. The method was evaluated by studying the occurrence of the three macrolides on a river and a WWTP in northern Colorado. None of the antibiotics were detected in the stream except immediately downstream of a WWTP, a result consistent with their presence in the influent and effluent of the treatment facility.     

Determination of volatile organic compounds in industrial wastewater plant air emissions by multi-sorbent adsorption and thermal desorption-gas chromatography-mass spectrometry

This paper describes the process of determining the presence of volatile organic compounds in air emissions from industrial wastewater treatment plants (WWTP). The analytical method, based on thermal desorption-gas chromatography-mass spectrometry, was developed to simultaneously determine of 99 volatile organic compounds (VOCs) in air samples. This method is rapid, environmentally-friendly (since no organic solvents are used to extract the analytes) and compatible with a large range of thermally stable polar and apolar compounds. The target VOCs were selected on the basis of their occurrence in real samples and their adverse effects on the environment and human health. To cover the wide range of target compounds, multisorbent tubes filled with Tenax TA and Carbograph 1TD were used. Method validation showed good repeatabilities, low detection limits, a high linear range and good recoveries. At a fixed sample volume of 600?mL no significant losses for any of the target compounds were found in the samples. Stability during storage indicated that samples must be keep refrigerated at 4°C and analysed within three days of collection. Real samples were taken from air emissions of an industrial wastewater treatment plant located in the Southern Industrial Area of Tarragona (Spain) with the aim of studying its contribution as a source of atmospheric VOCs. This WWTP collects wastewater from several chemical factories which produce isocyanates, polyurethanes, chlorinated organics and functional chemicals among other products. Samples from the collecting tank after the primary sedimentation showed higher VOC concentrations than samples from the secondary treatment tank. The most abundant VOCs found in these emissions are included in the USEPA List of Hazardous Air Pollutants. The highest values correspond to acrylonitrile (up to 1843?µg?m^?3) and styrene (up to 573.70?µg?m^?3). The levels of chloroform, 1,4-dioxane, ethylbenzene, 1,2,3-trimethylbenzene and 1,4-diethylbenzene were also high.     

Evaluating engineered nanoparticles in natural waters

With the accelerating introduction of engineered nanomaterials into commercial products and their potential use in water-treatment processes, it is inevitable that these materials will ultimately reside at some level in our recreational and drinking waters, thereby creating a critical need to detect and to quantify them in those media.Much is known about the diversity of engineered nanoparticles (ENPs) in the environment but almost nothing about their characterization and detection in the natural aquatic environment.There is no conventional treatment that can absolutely protect the consumer from exposure to ENPs either through recreational use or consumption of drinking waters. The question is whether this exposure poses a significant public health risk.Unfortunately, we are far from having methods to obtain data on occurrence levels, fate, and transport of ENPs in aquatic systems. Before a sound analytical approach can be developed, we need a fuller understanding of the nanomaterial domain which requires an evaluation of the matrix of source materials, their transformation in the natural aquatic environment, and their physical/chemical behavior that is specific to the water medium.We review characterization techniques that are used for identifying different types of ENP, and then, by extrapolation from isolation techniques appropriate for extracting ENPs from water, suggest approaches to analyzing them in a variety of waters.     

Sampling and analysis of volatile organics emitted from wastewater treatment plant and drain system of an industrial science park

Volatile organic compounds (VOCs) were monitored in the different sections of a wastewater treatment plant (WWTP), the outlet of both the WWTP and rainfall water, and the downstream of the WWTP joining the river in the area or vicinity of an industrial science park located in Hsinchu, Taiwan. Levels of VOCs were determined by collecting air samples over several sampling points and analyzed using gas chromatography. Among VOCs identified in the drainage and effluent system in each season, acetone, isopropanol (IPA) and dimethyl sulfide (DMS) were the major emission species and maximum concentrations were 400.4, 22.8 and 641.2 ppbv, respectively. The ambient air and wastewater sample analysis from neighboring wastewater streams identified pollutants being discharged from unaccounted sources other than the industrial park. According to the 24 h semi-continuous monitoring data (27/7/2002-29/7/2002), the total VOC concentration was an average of 93 ppbv (acetone contributed ∼78%) with a dramatic variation during the day and night. The emission rate of measured VOCs estimated using fixed box model projected an average of 2-4 μg m⁻² h⁻¹) during the day and 9-17 μg m⁻² h⁻¹ during the night. In addition, the isopleth maps show that the acetone and DMS emissions influence adversely the nearby residential area located at less than 100 m downwind from the plant. Eventually, based on this study, an on-line monitoring and alerting system could be built for a long-term performance, and with regular information on the varying pollutants over time construction of a green strategy and creation of a sustainable environment can be achieved.     

Review of analytical methods for the determination of estrogens and progestogens in waste waters

Steroid sex hormones and related synthetic compounds, e.g. those used in contraceptive pills, have been shown to be present in the aquatic environment, mainly as a result of inefficient removal in waste-water-treatment plants (WWTP). The concentrations of the compounds, although very low (low ng L(-1)), are sufficient to induce estrogenic responses and alter the normal reproduction and development of wildlife organisms. The compounds have been determined, by a variety of analytical procedures, in the influents and effluents of WWTP, within research programs conducted in different countries to evaluate the efficiency of the waste-water-treatment processes currently in use. Determination of natural and synthetic estrogens and progestogens in waste water is, however, a difficult analytical task, because the very low detection limits required and the complexity of the waste-water matrix necessitate the execution of a considerable number of steps. Thus, in general, complicated, time-consuming extraction and purification processes, usually based on the application of solid-liquid extraction, are performed before final determination by immunoassay, high-performance liquid chromatography, or, most often, gas chromatography coupled with mass spectrometry. This paper reviews the analytical methods so far described for the analysis of these important environmental pollutants in waste water and discusses the key procedural steps, from sampling to analysis, and the techniques most commonly used in the determination.     

Identification of toxic compounds in wastewater treatment plants during a field experiment

Chemical analysis and toxicity bioassays were used in conjunction to determine the toxic compounds present in wastewater. This combined methodology was applied to wastewater samples collected at two wastewater treatment plants (WWTP) from the area of Barcelona (Spain), during a field experiment carried out from 1-4 April 2000. The efficiency of the WWTP was evaluated by collecting and analyzing samples at various stages of the water treatment process. The samples corresponded to the raw influent, from first settlement—before biological treatment—and from the effluent.Two bioluminescence inhibition assays: ToxAlert^®10 and ToxAlert^®100 from Merck both based on the bioluminescence inhibition of Vibrio fischeri (marine bacterial specie) were used. ToxAlert^®10 is a portable device with no temperature control and uses freeze-dried bacterial reagent and ToxAlert^®100 uses liquid-dried bacterial reagent and the incubation takes place at controlled temperature. Both tests showed similar results.Besides the toxicity studies, the wastewater samples were characterized by various analytical protocols involving the use of solid phase extraction (SPE) followed by liquid chromatography-mass spectrometry (LC-MS). Phenols, non-ionic surfactants, linear alkyl benzene sulphonates, benzene and naphthalene sulphonates and micro-pollutants with high endocrine-disrupting effects like estradiol and ethynyl estradiol were identified at the WWTP.The toxic responses obtained for the samples collected at WWTP were defined by the 50% effective concentration (EC₅₀), the Toxicity Units (TU) and the toxicity impact index (TII₅₀). The toxic effect at the different steps of the WWTP was attributed to the compounds identified and quantified by LC-MS like transformation products of nonylphenol polyethoxylate such as nonylphenol and nonylphenol carboxylate.     

Evaluation of perfluorinated compounds in seven wastewater treatment plants in Beijing urban areas

The presence of perfluorinated compounds(PFCs)in seven major wastewater treatment plants(WWTPs)in Beijing was investigated in the current study.We detected nine PFCs in all the wastewater and sludge samples.Perfluorooctane acid(PFOA)is the dominant PFCs in influents and effluents,while perfluorooctane sulfonate(PFOS)is the major contaminant in sludge.The highest PFC concentration was found in plants at Qinghe and Jiuxianqiao WWTP,while the lowest was found at Fangzhuang WWTP.The total values of PFC range fr...     

Combustion of Waste Waters Containing Organic Alkaline Salts

Abstract

The biological treatment of waste waters from chemical industry containing organic and inorganic salts causes problems because these materials inhibit the metabolic activity of the bacteria. One possible and economically feasible way to convert the organic materials into less toxic forms is a thermal oxidation process, which can take place either in a fluidized bed combustor or in a vertical combustion chamber.

The process is described and parameters of the process are discussed. Results from particle measurements on a vertical combustion chamber for the combustion of various artificial waste waters are presented. The chemical analysis of the particulate matter from different stages of the process allows a detailed characterization of the decomposition of the organic material. Conclusions are drawn both with respect to the process and the environment.     

The determination of the linear alkylbenzene sulfonate isomers in water samples by gas-chromatography/mass spectrometry

A number of 20 compounds of linear alkylbenzene sulfonates (LASs) family were identified by electron impact mass spectrometry (EI-MS) in water samples collected from wastewater treatment plants (WWTP). This paper presents the mass spectra of 20 compounds, the proposed mechanism of formation of the diagnostic ions obtained by EI-MS and the distribution of individual isomers in water samples collected from compartments of WWTP. The individual isomers from four homolog series C(10)-, C(11)-, C(12)- and C(13)-LAS were analyzed as methyl derivatives.     

Element determination in natural biofilms of mine drainage water by total reflection X-ray fluorescence spectrometry

Human impacts like mining activities lead to higher element concentration in surface waters. For different pollution levels, the consequences for aquatic organisms are not yet investigated in detail. Therefore, the aim of this investigation is to determine the influence of mining affected surface waters on biofilms.Elements like heavy metals can be absorbed on cell walls and on polymeric substances or enter the cytoplasm of the cells. Thus, they are important for the optimization of industrial biotechnological processes and the environmental biotechnology. Beyond this, biofilms can also play an important role in wastewater treatment processes and serve as bioindicators in the aquatic environment.The presented total reflection X-ray fluorescence spectroscopic investigation was performed to compare the element accumulation behavior of biofilms grown on natural or on artificial materials of drainage water affected by former copper mining activities. A high salt and heavy metal pollution is characteristic for the drainage water. For an assessment of these results, samples from stream Schlenze upstream the confluence with the drainage water, a small tributary of the Saale River in central Germany, were analyzed, too.     

Secondary Effects of Hypochlorite Treatment on the Emerging Pollutant Candesartan: The Formation of Degradation Byproducts and Their Toxicological Profiles

In recent years, many studies have reported the frequent detection of antihypertensive agents such as sartans (olmesartan, valsartan, irbesartan and candesartan) in the influents and effluents of wastewater treatment plants (WWTPs) and in the superficial waters of rivers and lakes in both Europe and North America. In this paper, the degradation pathway for candesartan (CAN) was investigated by simulating the chlorination process that is normally used to reduce microbial contamination in a WWTP. Twelve isolated degradation byproducts (DPs), four of which were isolated for the first time, were separated on a C-18 column by employing a gradient HPLC method, and their structures were identified by combining nuclear magnetic resonance and mass spectrometry and comparing the results with commercial standards. On the basis of these results, a mechanism of formation starting from the parent drug is proposed. The ecotoxicity of CAN and its DPs was studied by conducting a battery of ecotoxicity tests; bioassays were performed using Aliivibrio fischeri (bacterium), Daphnia magna (planktonic crustacean) and Raphidocelis subcapitata (alga). The ecotoxicity results shed new light on the increased toxicity of DPs compared with the parent compound.     

Low-temperature Crystallizational Preconcentration of Impurities in Environmental Analysis

Phenols of natural and antropogenic derivations are respected to the dangerous and wide occurring organical impurities coining in the environment with waste waters of chemical plants. Maximum permissible concentration (MPC) of phenol for unchlorinated water is 0.1 mg/l, and for chlorinated one - 0.001-0.002 mg/l. For the determination of such small contents of phenol in waters preliminary extractional or sorptional concentration is used.