Water Wastewater Treatment Plants Research Articles

Impact of using stored treated municipal wastewater for irrigation on the microbial quality and safety of vegetable crops

Climate change is increasing the demand for alternative water sources, with treated municipal wastewater from a wastewater treatment plant (WWTP) standing out as a potential alternative. A field study was performed to examine the impact of storage on the microbial quality of water from a WWTP and the possible microbial transmission to three vegetable crops irrigated with (stored) water from a WWTP. The analysis consisted of 13 microbial indicators, hygiene and pathogenic parameters. Results showed that storing water from a WWTP up to 32 days can result in a decrease of 4.8 log CFU/100 ml E. coli and the absence of Salmonella spp. and Listeria monocytogenes. Additionally, integrating waiting periods of 7 days post-irrigation resulted in very limited microbial transmission to the irrigated crops. However, continuous research and monitoring are essential to apply this method in practice, due to the variability of crop type and type of bacteria. As of now, in order to meet European legislation (2020/741/EC) and depending on the impact of post-harvest processing, further water treatment (e.g. disinfection) is still needed to safely use stored WWTP water as an alternative water source for irrigation.

High efficiency removal of organic and inorganic iodine with ferrate[Fe(VI)] through oxidation and adsorption

I− is a halogen species existing in natural waters, and the transformation of organic and inorganic iodine in natural and artificial processes would impact the quality of drinking water. Herein, it was found that Fe(VI) could oxidize organic and inorganic iodine to IO3−and simultaneously remove the resulted IO3− through Fe(III) particles. For the river water, wastewater treatment plant (WWTP) effluent, and shale gas wastewater treated by 5 mg/L of Fe(VI) (as Fe), around 63 %, 55 % and 71 % of total iodine (total-I) had been removed within 10 min, respectively. Fe(VI) was superior to coagulants in removing organic and inorganic iodine from the source water. Adsorption kinetic analysis suggested that the equilibrium adsorption amount of I− and IO3− were 11 and 10.1 μg/mg, respectively, and the maximum adsorption capacity of IO3− by Fe(VI) resulted Fe(III) particles was as high as 514.7 μg/mg. The heterogeneous transformation of Fe(VI) into Fe(III) effectively improved the interaction probability of IO3− with iron species. Density functional theory (DFT) calculation suggested that the IO3− was mainly adsorbed in the cavity (between the γ-FeOOH shell and γ-Fe2O3 core) of Fe(III) particles through electrostatic adsorption, van der Waals force and hydrogen bond. Fe(VI) treatment is effective for inhibiting the formation of iodinated disinfection by-products in chlor(am)inated source water.

Adsorption of aqueous phase contaminants of emerging concern by activated carbon: Comparative fixed-bed column study and in situ regeneration methods

This work investigated the adsorption of five model contaminants of emerging concern (CECs) that are released daily in domestic effluents (caffeine, hydrochlorothiazide, saccharin, sulfamethoxazole and sucralose) onto two activated carbons (ACs), in fixed-bed column experiments with different aqueous matrices (ultrapure water, wastewater treatment plant (WWTP) effluent and WWTP effluent pretreated by reverse osmosis and photoperoxidation (reuse water)). The ACs were chemically similar, but AC1 had smaller particles (0.7–1.7 mm) and lower surface area (551 m2 g−1) than AC2 (1.2–2.4 mm and 716 m2 g−1). AC1 had a higher adsorption capacity (qads) for the CECs in the downflow mode. Overall, the qads values of the CECs followed the order: caffeine > sulfamethoxazole > hydrochlorothiazide = saccharin > sucralose. In the downflow mode, preferential pathways reduced the hydraulic retention time (HRT) of the fixed-bed column loaded with AC, which reduced the useful lifetime of column and the adsorption capacity. Nevertheless, the adsorption capacity and useful lifetime of the fixed-bed columns remained similar in the upflow mode (no preferential pathways were observed) regardless of the AC used. Since the HRTs were also found to be similar, it was evident that the crucial factor influencing the adsorption of the CECs was the HRT, which played a pivotal role in the overall process becoming evident. Compared to ultrapure water, use of the WWTP effluent reduced qads for all the CECs by up to 4.1 times, while reuse water reduced qads by up to 1.2 times. The AC1 could be in-situ regenerated using ethanol, with a global efficiency of 97.2 %. The results showed the importance of pretreatment techniques and optimization of the operational parameters, such as HRT, for enhancing the useful lifetime and qads of fixed-bed columns.

Circular Economy in Wastewater Treatment Plant—Water, Energy and Raw Materials Recovery

Nowadays, the main challenge for industrial and municipal enterprises is related to the tightening regulations and recommendations regarding environmental protection, which have been included in the circular economy (CE) package. Enterprises from all sectors, including water and sewage management, are obliged to actively participate in the CE transition. Modern wastewater treatment plants (WWTPs) should include actions aimed at a more sustainable use of available resources (water, energy, raw materials) to contribute to the protection of natural resources. In this way, they can be treated as resource facilities. This paper proposes a conceptual framework for a ‘Wastewater Treatment Plant of the Future’ that includes several technological solutions that take into account circular management of waste streams generated in WWTPs, such as wastewater (WW), sewage sludge (SS) and sewage sludge ash (SSA). Many actions have been already taken to modernize and build WWTPs that can respond to current and future challenges related to environmental protection. In the case of a CE ‘Wastewater Treatment Plant of the Future’, the recovery of water, energy and raw materials from available waste streams is strongly recommended. The implementation of CE solutions in analyzed facilities is incorporated into many strategies and policy frameworks, such as national and international (including European) documents. The proposed CE solutions could indirectly contribute to satisfying significant technological, social and environmental needs of the current and future generations, which is in line with sustainability principles.

Fault Type Diagnosis of the WWTP Dissolved Oxygen Sensor Based on Fisher Discriminant Analysis and Assessment of Associated Environmental and Economic Impact

Sensor failures are common events in wastewater treatment plant (WWTP) operations, resulting in ineffective monitoring and inappropriate plant management. Efficient aeration control is typically achieved by the dissolved oxygen (DO) control, and its associated sensor becomes critical to the whole WWTP’s reliable and economical operation. This study presents the Fisher discriminant analysis (FDA) used for fault diagnosis of the DO sensor of a currently operating municipal WWTP. Identification of the bias, drift, wrong gain, loss of accuracy, fixed value, complete failure minimum and maximum types of DO sensor fault was investigated. The FDA-proposed methodology proved efficiency and promptitude in obtaining the diagnosis decision. The consolidated fault identification showed an accuracy of 87.5% correct identification of the seven faulty and normal considered classes. Depending on the fault type, the results of the diagnosing time varied from 2.5 h to 16.5 h during the very first day of the fault appearance and were only based on observation data not included in the training data set. The latter aspect reveals the potential of the methodology to learn from incomplete data describing the faults. The rank of the fault type detection promptitude was: bias, fixed value, complete failure minimum, complete failure maximum, drift, wrong gain and loss of accuracy. Greenhouse gases (GHGs) such as nitrous oxide (N2O) and carbon dioxide (CO2) emitted during wastewater treatment, electrical energy quantity in association with costs spent in the WWTP water line and clean water effluent quality were ranked and assessed for the normal operation and for each of the DO sensor faulty regimes. Both for CO2 and N2O, the on-site emissions showed the most significant GHG contribution, accounting for about three-quarters of the total emissions. The complete failure maximum, fixed value and loss of accuracy were the DO sensor faults with the highest detrimental impact on GHG-released emissions. The environmental and economic study reveals the incentives of the proposed DO sensor faults identification for the WWTP efficient and environmentally friendly operation.

The hydrogen economy - Where is the water?

“Green hydrogen”, i.e. hydrogen produced by splitting water with a carbon “free” source of electricity via electrolysis, is set to become the energy vector enabling a deep decarbonisation of society and a virtuous water based energy cycle. If to date, water electrolysis is considered to be a scalable technology, the source of water to enable a “green hydrogen” economy at scale is questionable. Countries with the highest renewable energy potential like Australia, are also among the driest places on earth. Globally 380,000 GL/year of wastewater is available, and this is much more than the 34,500 GL/year of water required to produce the projected 2.3 Gt of hydrogen of a mature hydrogen economy. Hence the need to assess both technically and economically whether some wastewater treatment effluent, are a better source for green hydrogen. Analysis of Sydney Water's wastewater treatment plants alone shows that these plants have 37.6 ML/day of unused tertiary effluents, which if electrolysed would generate 420,000 t H2/day or 0.88 Mt H2/year, and cover ∼100% of Australia's estimated production by 2030. Furthermore, the production of oxygen as a by-product of the electrolysis process could lead to significant benefits to the water industry, not only in reducing the cost of the hydrogen produced for $3/kg (assuming a price of oxygen of $3–4 per kg), but also in improving the environmental footprint of wastewater treatment plants by enabling the onsite re-use of oxygen for the treatment of the wastewater. Compared to desalinated water that requires large investments, or stormwater that is unpredictable, it is apparent that the water utilities have a critical role to play in managing water assets that are “climate independent” as the next “golden oil” opportunity and in enabling a “responsible” hydrogen industry, that sensibly manages its water demands and does not compete with existing water potable water demand.

Emerged macrophytes to the rescue: Perfluoroalkyl acid removal from wastewater and spiked solutions

This study evaluated the potential for three emergent aquatic macrophytes to remove perfluoroalkyl acids (PFAAs) from contaminated waters in constructed wetland systems. Three plants (Iris pseudacorus L., Phragmites australis (Cav.) Trin. Ex Steud., and Typha latifolia L.) were exposed to an effluent from a tannery wastewater treatment plant (WWTP) that contained residual PFAAs, and to three spiked solutions with increasing concentrations of 11 perfluorocarboxylic acids (PFCAs) and three perfluorosulfonic acids (PFSAs) (500, 2500, and 5000 ng L−1, each). Thirty-six lightweight expanded clay aggregate- and vegetation-filled tanks (0.35 × 0.56 × 0.31 m) were exposed to the tested solutions at the Acque del Chiampo SpA WWTP in Arzignano (NE Italy). Throughout the experiment, PFAA concentrations and physicochemical water parameters were monitored via measures of the clay material, plastic tank inner surfaces, and below- and above-ground biomasses (after harvest). Vegetation growth was shown to be unaffected by increased PFAA levels in the spiked solutions. Alternatively, total biomass was significantly reduced when WWTP water was used, although we attribute this finding to the relatively high salinity that mainly restricted Typha and Iris development. The tested macrophytes were found to remove a significant PFAA mass from the contaminated waters (36% to ca. 80%, on average) when Phragmites was subjected to the highest PFAA concentrations. Such large accumulations were primarily associated with long C-chain PFAA stabilization in belowground biomass (26%, on average). Most PFAA translocations were observed in Typha, which accumulated mostly short perfluorinated C-chain PFBA, PFPeA, and PFHxA in the aboveground biomass (16%, on average). Despite some growth limitations, Iris was still the most efficient macrophyte for translocating PFBS under WWTP.

Characterization of bacterial diversity in wastewater of Indian paper industries with special reference to water quality

The bacterial diversity in terms of structure and community profile, with special reference to water quality in the wastewater treatment plant of Indian paper industries, is poorly understood. In the present work, characterization of bacterial diversity using 16S (V3-V4 region) rRNA gene amplicon sequencing data with reference to physicochemical parameters in the wastewater treatment plant of two paper industries has been carried out. Amplicon data analysis revealed the presence of bacterial taxa belonging to the phylum such as Bacteroidetes, Proteobacteria, Patescibacteria, Firmicutes, Actinobacteria, etc. Further, taxonomic classification upto genus level and functional analysis data indicated that genera such as Cloacibacterium, Aerococcus, Chryseobacterium, Microbacterium, Acinetobacter, Sphingobium, etc., were involved in the predicted metabolic pathways like carbohydrate metabolism, fatty acid and aromatic compounds biosynthesis as well as degradation. Canonical correspondence analysis confirmed a significant correlation between the microbial pollutions loads and physicochemical parameters. Further, the chemical oxygen demand, biochemical oxygen demand and total suspended solids exceeded the acceptable limits prescribed by Central Pollution Control Board New Delhi, Government of India, for discharge of wastewater. This study finds the correlation between the bacterial community residing in the polluted water of wastewater treatment plant and their environmental preferences. The presence of these bacterial diversity in the wastewater treatment plant of paper industries may affect the maintenance as well as paper quality. In future, it will provide a benchmark for the better understanding and management of wastewater treatment plant in paper industries across the globe.

Dairy wastewater processing and automatic control for waste recovery at the municipal wastewater treatment plant based on modelling investigations

Based on the calibrated model for an Anaerobic-Anoxic-Oxic (A2O) municipal wastewater treatment plant (WWTP), this research investigated and proposed feasible solutions, control system configurations and optimal operating conditions for the dairy wastewater processing. The steady state study on adding different daily amounts of dairy wastewater in the WWTP water line revealed the most efficient amount to be treated by finding a minimum of the total nitrogen concentration in the water effluent. The dynamic investigations on adding different daily amounts of diary wastewater demonstrated the incentives of the proposed cascade control system configurations, based on the ammonia or nitrates concentration control in the aerated reactors, associated to nitrates and nitrites concentration control in the anoxic reactor. The best periods of time and duration for scheduling the dairy wastewater processing were searched and found. Preliminary results showed the incentives of the additional dairy wastewater distribution during 2 h, at the highest influent concentration moments. Further investigations, relying on the genetic algorithm optimization method revealed that better daily scheduling of the dairy wastewater addition may be obtained. Compared to normal operation, the optimal scheduling program of the dairy wastewater treatment showed an overall performance index improvement of 13.36%, when the daily 1:52 p.m. moment of time and the duration of about 1 h program, found by optimization, were applied. Results demonstrate the dual incentives of the carbon and nutrients recovery, associated to the energy and effluent quality benefits on WWTP operation.

A Novel Check-List Strategy to Evaluate the Potential of Operational Improvements in Wastewater Treatment Plants

With increasing demands for cleaning and purification of water, wastewater treatment plants (WWTP) require their most efficient operation. The operators are thus obliged to constantly review the efficiency of the processing units and technological equipment of WWTPs and seek opportunities for improvements. To increase the efficiency of particular equipment, the important parameters to be used for the intensification must be correctly selected. A common WWTP consists of different types of processing units, where the basic parameters can be changed to achieve the highest efficiency (i.e., maximum output with minimum energy consumption) in the WWTP. However, due to many possible technologies in the wastewater treatment process, the combinations of processing units can be complex. In such cases, the efficiency assessment can be misleading if only basic parameters were accessed. Moreover, single-unit intensification can potentially improve the efficiency of the unit itself but cannot guarantee full process improvement. This can be due to negative causal effects in the downstream due to that unit intensification. This work reviews of key parameters at five selected pieces of WWTP equipment (inlet pump station, airlift pump, primary sedimentation tank, aeration chamber, and mixing of anaerobic digester) to demonstrate the correct selection of all affected parameters for the efficiency assessment. In the context of the whole WWTP process, it is necessary to take into account several other parameters to evaluate the efficiency of the equipment. Finally, a methodology for assessing the significance of the identified parameters is proposed. This methodology is effectively applied and demonstrated in the WWTP case study.

Characteristics of Dissolved Organic Matter in Tail Water of Wastewater Treatment Plant and its Influence on Receiving River

The dissolved organic matter (DOM) in the tail water of the municipal wastewater treatment plant (WWTP) are complex and changeable, and can react with the organic and metal ions in the receiving water, thus affecting their migration and transformation. In order to understand the characteristics of DOM in the tail water of WWTP, the Guozhen WWTP and Kui river in Xuzhou city were taken as the research objects. The spectral characteristics of DOM were analysed by three dimensional fluorescence spectroscopy (3D-EEM), and the water quality indexes such as pH, total nitrogen (TN), ammonia nitrogen (NH3 −-N), nitrate nitrogen(NO3 −-N), nitrite nitrogen(NO2 −-N), TOC and UV254 were measured. The changing rules of these indexes in sewage, tail water and receiving river were discussed. The results showed that DOM in the tail water was mainly composed of soluble microbial metabolites and humic acids. The TN, NH3-N, NO3 −-N, NO2 −-N and TOC have been significantly reduced under the biological treatment process of the WWTP, but the large-scale drainage of the tail water will still have no negligible influence on the natural waterbody.

Enhanced Transformation of Emerging Contaminants by Permanganate in the Presence of Redox Mediators.

In this study, a permanganate/redox mediator system for enhanced transformation of a series of emerging contaminants was evaluated. The presence of various redox mediators (i.e., 1-hydroxybenzotriazole, N-hydroxyphthalimide, violuric acid, syringaldehyde, vanillin, 4-hydroxycoumarin, and p-coumaric acid) accelerated the degradation of bisphenol A (BPA) by Mn(VII). Since 1-hydroxybenzotriazole (HBT) exhibited the highest reactive ability, it was selected to further investigate the reaction mechanisms and quantify the effects of important reaction parameters on Mn(VII)/redox-mediator reactions with BPA and bisphenol AF (BPAF). Interestingly, not only HBT accelerated the degradation of BPA, but also BPA enhanced the decay of HBT. Evidence for the in situ formation of HBT· radicals as the active oxidant responsible for accelerated BPA and BPAF degradation was obtained by radical scavenging experiments and 31P NMR spin trapping techniques. The routes for HBT· radical formation involving Mn(VII) and the electron-transfer pathway from BPA/BPAF to HBT· radicals demonstrate that the Mn(VII)/HBT system was driven by the electron-transfer mechanism. Compared to Mn(VII) alone, the presence of HBT totally inhibited self-coupling of BPA and BPAF and promoted β-scission, hydroxylation, ring opening, and decarboxylation reactions. Moreover, Mn(VII)/HBT is also effective in real waters with the order of river water > wastewater treatment plant (WWTP) effluent > deionized water.

Pilot-scale study on advanced treatment of tail water of urban sewage treatment plant by constructed wetlands with different plants

利用种植不同植物的人工湿地对污水厂尾水进行深度处理以达到更严格的排放标准.利用5块尺寸一致的中试规模人工湿地，以潮汐流作为运行方式，研究不同植物对尾水的处理效果.经过一年的实验，结果表明：5块人工湿地出水各指标均能达到提升标准的排放要求.在不同植物的去污效果对比实验中，种植芦苇（Phragmites communis）的人工湿地对化学需氧量（COD）、氨氮和总氮（TN）的平均去除率均为最高，分别为24.01%、68.15%和92.70%；种植风车草（Cyperus alternifolius）的人工湿地对TP的平均去除率最高，为71.68%.在不同季节的去污效果对比实验中，春季芦苇湿地对COD、氨氮和TN的去除效果最好，平均去除率分别为52.51%、76.06%和92.04%，美人蕉（Canna indica）湿地对TP去除效果最好，平均去除率为66.72%；夏季对COD、氨氮、TP和TN处理效果最好的分别是种植丝带草（Phalaris arundinacea）、菖蒲（Acorus calamus）、风车草和芦苇的人工湿地，平均去除率分别为15.83%、78.11%、67.30%和91.73%；秋季对COD、氨氮、TP、TN处理效果最好的分别是种植芦苇、丝带草、风车草、美人蕉的人工湿地，平均去除率分别为12.19%、58.82%、83.16%和94.01%；冬季对COD去除效果最好的是种植丝带草的人工湿地，平均去除率为33.39%，对氨氮、TP处理效果最好的是种植美人蕉的人工湿地，平均去除率分别为76.33%和79.43%，对TN处理效果最好的是种植芦苇的人工湿地，平均去除率为94.97%.在以后的实际工程中，可以考虑用种植不同季节、不同指标对应的最佳去污植物为主，并且搭配种植其他植物的人工湿地进行污水厂尾水的深度处理.;In order to meet stringent water quality standards, the tail water of the local wastewater treatment plant has been treated by constructed wetlands with different plants. Five pilot-scale constructed wetlands were investigated for the advanced treatment of the tail water of wastewater treatment plant, they had the same size, and were operated with a tidal flow, while they were planted with different plants to compare their treatment effects. After one year's experiment, the results showed that the all indexes of effluent from five constructed wetlands could meet the improved requirements. Among them, the constructed wetland planted with Phragmites communis had the highest average removal rates of chemical oxygen demand (COD), ammonia nitrogen, and total nitrogen (TN), which were 24.01%, 68.15%, and 92.70%, respectively. The constructed wetland planted with Cyperus alternifolius had the highest average removal rate of total phosphorus (TP), which was 71.68%. In the contrast experiment of the performance in different seasons, in the spring, the constructed wetland planted with Phragmites communis had the best removal effect on COD, ammonia nitrogen and TN, the average removal rates were 52.51%, 76.06% and 92.04%, respectively, and the constructed wetland planted with Canna indica had the best removal effect on TP, the average removal rate was 66.72%. In the summer, the constructed wetland respectively planted with Phalaris arundinacea, Acorus calamus, Cyperus alternifolius and Phragmites communis had the best removal effect on COD, ammonia nitrogen, TP and TN, the average removal rates were 15.83%, 78.11%, 67.30% and 91.73%, respectively. In the autumn, the constructed wetland respectively planted with Phragmites communis, Phalaris arundinacea, Cyperus alternifolius and Canna indica had the best removal effect on COD, ammonia nitrogen, TP and TN, respectively, the average removal rates were 12.19%, 58.82%, 83.16% and 94.01%, respectively. In the winter, the constructed wetland planted with Phalaris arundinacea had the best removal effect on COD, the average removal rate was 33.39%, the constructed wetland planted with Canna indica had the best removal effect on ammonia nitrogen and TP, the average removal rates were 76.33% and 79.43%, respectively, and the constructed wetland planted with Phragmites communis had the best removal effect on TN, the average removal rate was 94.97%. It will be of significance to the practical engineering in the future.

Verification of an alternative sludge treatment process for pathogen reduction at two wastewater treatment plants in Victoria, Australia.

At South East Water wastewater treatment plants (WwTPs) in Victoria, Australia, biosolids are stockpiled for three years in compliance with the State guidelines to achieve the highest pathogen reduction grade (T1), suitable for unrestricted use in agriculture and landscaping. However, extended stockpiling is costly, may increase odour nuisance and greenhouse gas emissions, and reduces the fertiliser value of the biosolids. A verification programme of sampling and analysis for enteric pathogens was conducted at two WwTPs where sludge is treated by aerobic and anaerobic digestion, air drying (in drying pans or solar drying sheds) and stockpiling, to enumerate and, if present, monitor the decay of a range of enteric pathogens and parasites. The sludge treatment processes at both WwTPs achieved T1 grade biosolids with respect to prescribed pathogenic bacterial numbers (<1 Salmonella spp. 50 g-1 dry solids (DS) and <100 Escherichia coli g-1 DS) and >3 log10 enteric virus reduction after a storage period of one year. No Ascaris eggs were detected in the influent to the WwTPs, confirming previous studies that the presence of helminth infections in Victoria is extremely low and that Ascaris is not applicable as a control criterion for the microbiological quality of biosolids in the region.

Perfluoroalkyl acids in aqueous samples from Germany and Kenya.

Continuous monitoring of chemicals in the environment is important to control their fate and to protect human health, flora, and fauna. Perfluoroalkyl acids (PFAAs) have been detected frequently in different environmental compartments during the last 15years and have drawn much attention because of their environmental persistence, omnipresence, and bioaccumulation potential. Water is an important source of their transport. In the present study, distributions of PFAAs in river water, wastewater treatment plant (WWTP) effluent, and tap water from eastern part of Germany and western part of Kenya were investigated. Eleven perfluorocarboxylic acids (PFCAs) and five perfluorosulfonic acids (PFSAs) were analyzed using liquid chromatography/tandem mass spectrometry. Sum of mean concentrations of eight PFAAs detected in drinking tap water from Leipzig was 11.5ngL-1, dominated by perfluorooctanoic acid (PFOA, 6.2ngL-1). Sums of mean riverine concentrations of PFAAs detected in Pleiße/White Elster, Saale, and Elbe (Germany) were 24.8, 54.3, and 26.8ngL-1, respectively. Annual flux of PFAAs from River Saale was estimated to be 164 ± 23kga-1. The effluent of WWTP in Halle was found to contain four times higher levels of PFAAs than river water and was dominated by perfluorobutane sulfonate (PFBS) with 32 times higher concentration than the riverine level. It advocates that WWTPs are the point source of contaminating water bodies with PFAAs, and short-chain PFAAs are substituting long-chain homologues. Sums of mean riverine concentrations of PFAAs in Sosiani (Kenya) in samples from sparsely populated and densely populated areas were 58.8 and 109.4ngL-1, respectively, indicating that population directly affected the emissions of PFAAs to surface waters. The discussion includes thorough review and comparison of recently published literature reporting occurrence of PFAAs in aqueous matrices. Graphical abstract Perfluoroalkyl acids in aqueous matrices.

교반막대 추출법과 GC-MS/MS를 이용한 수중의 합성 향물질류 분석

A highly sensitive analytical method based on stir bar sorptive extraction (SBSE) technique and gas chromatography/ tandem mass spectrometry (GC-MS/MS) has been developed, allowing the simultaneous multi-analyte determination of 11 synthetic fragrances (SFs) in water samples. The stir bar coated with polydimethylsiloxane (PDMS) was added to 40 mL of water sample at pH 3 and stirred at 1,100 rpm for 120 min. Other SBSE parameters (salt effect and presence of organic solvent) were optimised. The method shows good linearity (coefficients > 0.990) and reproducibility (RSD < 10.9%). The extraction efficiencies were above 83% for all the compounds. The limits of detections (LOD) and limits of quantification (LOQ) were 2.1~4.1 ng/L and 6.6~12.9 ng/L, respectively. The developed method offers the ability to detect 11 SFs at ultra-low concentration levels with only 40 mL of sample volume. Matrix effects in tap water, river water, wastewater treatment plant (WWTP) final effluent water and seawater were investigated and it was shown that the method is suitable for the analysis of trace level of 11 SFs. The method developed in the present study has the advantage of being rapid, simple, high-sensitive and both user and environmentally friendly.

교반막대 추출법과 GC/MS-MS를 이용한 수중의 자외선 차단제 분석

A highly sensitive analytical method based on stir bar sorptive extraction (SBSE) technique and gas chromatography/tandem mass spectrometry (GC/MS-MS) has been developed, allowing the simultaneous multi-analyte determination of seven UV filters in water samples. The stir bar coated with polydimethylsiloxane (PDMS) was added to 40 mL of water sample at pH 3 and stirred at 1,100 rpm for 120 min. Other SBSE parameters (salt effect and presence of organic solvent) were optimised. The method shows good linearity (coefficients > 0.990) and reproducibility (RSD < 12.9%). The extraction efficiencies were above 84% for all the compounds. The limits of detections (LOD) and limits of quantification (LOQ) were 2.1∼8.6 ng/L and 6.8∼27.5 ng/L, respectively. The developed method offers the ability to detect 8 UV filters at ultra-low concentration levels with only 40 mL of sample volume. Matrix effects in tap water, river water, wastewater treatment plant (WWTP) final effluent water and seawater were investigated and it was shown that the method is suitable for the analysis of trace level of 7 UV filters except of benzophenone (BP). The method developed in the present study has the advantage of being rapid, simple, high-sensitive and both user and environmentally friendly.

Contamination of nonylphenolic compounds in creek water, wastewater treatment plant effluents, and sediments from Lake Shihwa and vicinity, Korea: Comparison with fecal pollution

Nonylphenolic compounds (NPs), coprostanol (COP), and cholestanol, major contaminants in industrial and domestic wastewaters, were analyzed in creek water, wastewater treatment plant (WWTP) effluent, and sediment samples from artificial Lake Shihwa and its vicinity, one of the most industrialized regions in Korea. We also determined mass discharge of NPs and COP, a fecal sterol, into the lake, to understand the linkage between discharge and sediment contamination. Total NP (the sum of nonylphenol, and nonylphenol mono- and di-ethoxylates) were 0.32–875 μg L −1 in creeks, 0.61–87.0 μg L −1 in WWTP effluents, and 29.3–230 μg g −1 TOC in sediments. Concentrations of COP were 0.09–19.0 μg L −1 in creeks, 0.11–44.0 μg L −1 in WWTP effluents, and 2.51–438 μg g −1 TOC in sediments. The spatial distributions of NPs in creeks and sediments from the inshore region were different from those of COP, suggesting that Lake Shihwa contamination patterns from industrial effluents differ from those from domestic effluents. The mass discharge from the combined outfall of the WWTPs, located in the offshore region, was 2.27 kg d −1 for NPs and 1.00 kg d −1 for COP, accounting for 91% and 95% of the total discharge into Lake Shihwa, respectively. The highest concentrations of NPs and COP in sediments were found in samples at sites near the submarine outfall of the WWTPs, indicating that the submarine outfall is an important point source of wastewater pollution in Lake Shihwa.

Development of a multi-residue method for the determination of organic micropollutants in water, sediment and mussels using gas chromatography–tandem mass spectrometry

This study describes the development of a multiresidue method based on gas chromatography–electron ionization-tandem mass spectrometry (GC–EI-MS/MS) for the detection of sixteen polycyclic aromatic hydrocarbons (PAHs), five phthalate esters (PEs), seven polychlorinated biphenyls (PCBs), six polybrominated diphenyl ethers (PBDEs), six alkylphenols (APs), three organochlorined pesticides and their isomers or degradation products (OCPs) and bisphenol A in seawater, river water, wastewater treatment plant (WWTP) effluents, sediments and mussels. Solid phase extraction (SPE) was used for the extraction of target analytes in aqueous samples, and ultrasound assisted extraction for solid samples. GC–EI-MS/MS acquisition conditions in selected reaction monitoring (SRM) using two transitions per compound were optimized. In this way, quantification and unequivocal identification of organic micropollutants were performed in compliance with the Decision 2002/657/EC. Good linearity responses with coefficients of determination higher than 0.99 were obtained. Methodological detection limits (MDLs) in seawater ranged from 0.1 to 6 ng L −1; in river water from 0.1 to 4.8 ng L −1; in WWTP effluents from 1 to 75 ng L −1; in sediments from 1 to 150 ng g −1 and in mussels from 1 to 125 ng g −1. MDLs and recovery yields were compared with other published methods and similarities or even improvements were achieved. The optimized method was applied to analyze five samples from each matrix collected in coastal areas, showing its potential use for marine pollution monitoring.

ANISOPS SARDEUS SARDEUS HERRICH-SCHAEFFER (HETEROPTERA: NOTONECTIDAE) AS A BIOINDICATOR OF HEAVY METALS IN WASTEWATER TREATMENT PLANT AT ISMAILIYA, EGYPT

Heavy metal contents of Anisops sardeus sardeus HerrichSchaeffer collected from polishing and facultative lagoons in Ismailiya Wastewater Treatment Plant, Egypt, were analyzed by AAS. This species is studied for the first time as a biomonitor of heavy metals in water and sediment. The average concentrations of heavy metals in insect tissues found in facultative lagoon vs. the polishing lagoon were: Zn 197,147.4; Cd 2.7,1.5; Cu 28.2,13.7; Co 37.7, 34.4; Pb 59.7, 57.8; Ni 36.9, 25.1 |ig/g dry weight respectively. With the exception of lead, the differences in concentrations of each metal were statistically significant. These concentrations of metals in the insect tissues corresponded to their concentrations in the two lagoons. The present study confirmed that Anisops sardeus sardeus from polishing lagoon is an excellent accumulator of Co and Pb as their concentrations reached 34.4 and 57.8 jig/g diy weight, respectively, than in water (9.1 and 41.0 mg/1) and sediment (29.0 and 42.0 }ig/g) samples. The bioaccumulation factor was 12.3, 1.5, 1.3, 3.8, 1.4 and 03 for Zn, Cd, Cu, Co, Pb and Ni, respectively. It is, thus, concluded that Anisops sardeus sardeus could be a very suitable accumulative bioindicator for the monitoring of heavy metals in surface water of wastewater treatment plant.