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Landfills and wastewater treatment plants (WWTP) are point sources for many emerging contaminants, including microplastics and per- and polyfluoroalkyl substances (PFAS). Previous studies have estimated the abundance and transport of microplastics and PFAS separately in landfills and WWTPs. In addition, previous studies typically report concentrations of microplastics as particle count/L or count/g sediment, which do not provide the information needed to calculate mass balances. We measured microplastics and PFAS in four landfill-WWTP systems in Illinois, USA, and quantified mass of both contaminants in landfill leachate, WWTP influent, effluent, and biosolids. Microplastic concentrations in WWTP influent were similar in magnitude to landfill leachates, in the order of 10 2  μg plastic/L (parts-per-billion). In contrast, PFAS concentrations were higher in leachates (parts-per-billion range) than WWTP influent (parts-per-trillion range). After treatment, both contaminants had lower concentrations in WWTP effluent, although were abundant in biosolids. We concluded that WWTPs reduce PFAS and microplastics, lowering concentrations in the effluent that is discharged to nearby surface waters. However, partitioning of both contaminants to biosolids may reintroduce them as pollutants when biosolids are landfilled or used as fertilizer., Competing Interests: Declaration of competing interest There is no conflict of interest associated with this manuscript., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Widespread wastewater pollution is one of the biggest challenges threatening the ecological health of rivers. It is crucial to identify the toxic changes of effluents after entering urban rivers as well as the toxic substances in the complex chemical mixtures found in these urban rivers. This study used HepG2 cell line for cytotoxicity test to evaluate the ecological impact of effluents on urban rivers. Water samples were collected from the Xingwu River and Yunliang River in Nanjing, China. The bacterial communities in the lower reaches of urban rivers were altered due to the differences in total nitrogen and nitrate nitrogen. The complex chemical mixtures collected in the urban rivers were divided into 10 fractions, >100 chemicals were screened in each fraction. The substances with LC 50  < 1000 mg/L were listed as toxic substances, and the number of toxic substances dominated the toxicity of urban rivers. Our study highlights toxicity as a comprehensive indicator for assessing river pollutants and reveals relationship between the number of toxic substance and river toxicity. These findings have direct implications for the monitoring and management of environmental stressors and the protection of aquatic organisms and human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

A key component in a nation's economic progress is industrialization, however, hazardous heavy metals that are detrimental to living things are typically present in the wastewater produced from various industries. Therefore, before wastewater is released into the environment, it must be treated to reduce the concentrations of the various heavy metals to maximum acceptable levels. Even though several biological, physical, and chemical remediation techniques are found to be efficient for the removal of heavy metals from wastewater, these techniques are costly and create more toxic secondary pollutants. However, phytoremediation is inexpensive, environmentally friendly, and simple to be applied as a green technology for heavy metal detoxification in wastewater. The present study provides a thorough comprehensive review of the mechanisms of phytoremediation, with an emphasis on the possible utilization of plant species for the treatment of wastewater containing heavy metals. We have discussed the concept, its applications, advantages, challenges, and independent variables that determine how successful and efficient phytoremediation could be in the decontamination of heavy metals from wastewater. Additionally, we argue that the standards for choosing aquatic plant species for target heavy metal removal ought to be taken into account, as they influence various aspects of phytoremediation efficiency. Following the comprehensive and critical analysis of relevant literature, aquatic plant species are promising for sustainable remediation of heavy metals. However, several knowledge gaps identified from the review need to be taken into consideration and possibly addressed. Therefore, the review provides perspectives that indicate research needs and future directions on the application of plant species in heavy metal remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The disposal of pharmaceutical wastewater has gained increasing attention due to its potential adverse effects on the environment and public health. This study aims to assess the concentration of pharmaceutical contaminants and their toxicity to aquatic organisms. A qualitative research approach was used. Composite samples were collected from the effluent storage system. Various analytical techniques, including high-performance liquid chromatography (HPLC), were employed to detect and quantify pharmaceutical compounds in wastewater samples. The results revealed various pharmaceutical compounds (ibuprofen 28  μ g/L, diclofenac 27.20  μ g/L, paracetamol 22.03  μ g/L, and tramadol <0.01  μ g/L) in the wastewater. The maximal environmental concentration (MEC) for all the detected pharmaceuticals was high; hence, the risk quotients (RQs) indicated potential toxicity (RO > 1). It further indicates that the effluent was more toxic to animals (daphnia and fish) than algae (plants). It can be concluded that pharmaceutical effluent was toxic to aquatic organisms. Therefore, there is a need to implement stringent regulatory measures to mitigate untreated pharmaceutical effluent in water bodies. Addressing pharmaceutical contaminants in wastewater is crucial to safeguarding the environment and public health in an increasing pharmaceutical use and production era., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Lyndon N. A. Sackey et al.)

UV filters and benzotriazole UV stabilizers are considered emerging contaminants in the environment. LC-MS/MS and GC-MS methods, involving a single solid phase extraction protocol, were developed and validated to determine eight UV filters and seven UV stabilizers, respectively in wastewater from a wastewater treatment plant (WWTP) in Lüneburg, Germany. The LC-MS/MS method exhibited extraction recoveries of ≥ 71% at six different fortification levels with limits of detection (LODs) range of 0.02 ng mL -1 - 0.09 ng mL -1 . Extraction recoveries of 47 to 119% at six different fortification levels were obtained for the GC-MS method with LODs range of 0.01 - 0.09 ng mL -1 . Among the UV filters, the highest mean concentration was determined for octocrylene (OCR) in influent (3.49 ng mL -1 ) while the highest mean concentration was measured for 2-hydroxy-4-octyloxybenzophenone (UV 531) in influent (0.44 ng mL -1 ) among the UV stabilizers. Potential risk to aquatic organisms was assessed by the risk quotient approach. Only OCR presented a high risk to aquatic invertebrates whereas 2-ethylhexyl 4-methoxycinnamate (EHMC) and 2-ethylhexyl salicylate (EHS) posed high risks to algae. Benzotriazole UV stabilizers presented negligible risks to aquatic invertebrates and fish. This work reports the detection of rarely studied 4-aminobenzoic acid (PABA) and UV 531 in WWTP influent and effluent. The occurrence and risk assessment of target benzotriazole UV stabilizers in wastewater from a German WWTP was demonstrated for the first time., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The dissolved carbon cycling in river system fueled by wastewater treatment plant effluent have been a research hotspot. However, the composition of dissolved carbon (DC) in wastewater effluents from karst regions remains poorly understood, resulting in a lack of clarity regarding its impact on the dynamics of dissolved carbon in karst rivers. To address this knowledge gap, this study investigated variations of dissolved inorganic (DIC) and organic C (DOC) components in effluent in karst regions and preliminarily discussed their influence on the DC cycling in karst rivers. The results showed that bicarbonate (HCO 3 - ) in WWTP effluents makes more than 90% of the total dissolved inorganic carbon (DIC). The partial pressure of aqueous CO 2 ) of the effluent reached 14450 ± 10084μtam, and pCO 2 level declined with increasing river distance from the effluent discharge, effluent acted as a strong CO 2 level declined with increasing river distance from the effluent discharge, effluent acted as a strong CO 2 concentrations in effluent. PHREEQC mixing simulation together with filed samples data indicated that the DIC species can be changed, and pCO 2 increased in receiving karst river water after mixed with effluent. The dissolved organic carbon (DOC) of effluent contained humic-like and protein-tryptophan-like, both of them appeared important and recent autochthonous, which could interfere the distinguish the sources of DOC in receiving karst river water. Thus, these findings highlight that the effluent can be an essential factor for the changes of the karst riverine DC pool, which advance our understanding on karst riverine DC evolution under anthropogenic activities. As more than 30% of the earth surface in China, northern America, and Europe are covered by carbonate rocks, this study has relevant implications for other karst regions as it underscores the influence of WWTP effluents on the carbon cycle in karst rivers. Such information and knowledge are valuable for monitoring and managing effluent-receiving river in other karst regions in the world.2 increased in receiving karst river water after mixed with effluent. The dissolved organic carbon (DOC) of effluent contained humic-like and protein-tryptophan-like, both of them appeared important and recent autochthonous, which could interfere the distinguish the sources of DOC in receiving karst river water. Thus, these findings highlight that the effluent can be an essential factor for the changes of the karst riverine DC pool, which advance our understanding on karst riverine DC evolution under anthropogenic activities. As more than 30% of the earth surface in China, northern America, and Europe are covered by carbonate rocks, this study has relevant implications for other karst regions as it underscores the influence of WWTP effluents on the carbon cycle in karst rivers. Such information and knowledge are valuable for monitoring and managing effluent-receiving river in other karst regions in the world., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

In this study, dairy industry wastewater was collected and used as a protein source. The proteins were converted into powder form using lyophilization. The proteins were digested using Bacillus subtilis (B. subtilis) NCIM 2724. The maximum degree of hydrolysis (DH) of protein was observed at pH of 7, 30 °C incubation temperature, 120 rpm shaking speed, and 96 h incubation. The tris-glycine sodium dodecyl sulfate-polyacrylamide (tris-glycine-SDS) gel electrophoresis showed the disappearance of large molecular weight proteins due to the proteolytic action of B. subtilis. The resulting digest was fractionated using a 3 kDa membrane filter. The antioxidant activity of the obtained fractions was evaluated. Antioxidant activity of digest and filtrate was found to be 12.78% (±0.040) and 49% (±0.025), respectively, at a concentration of 50 mg/mL. The 3 kDa filtrate was subjected to liquid chromatography-mass spectrometry (LCMS) analysis. Bioinformatics tools were used to predict the sequences of antioxidant peptides. Furthermore, the 3 kDa filtrate was used for the synthesis of antioxidant nanohybrid. Scanning electron microscopy (SEM)-energy dispersive spectroscopy (EDS) confirmed the nanohybrid formation and encapsulation of peptides. The antioxidant nanohybrid showed enhanced antioxidant activity compared to the free peptide solution. The dairy industry has a significant environmental impact due to high water use and waste generation. This study addresses an important issue of recycling protein-containing wastewater and the potential to be used for converting these proteins into antioxidant peptides. Such practices will help to reduce environmental impact and sustainably operate the industry., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Recycled building debris has recently emerged as a suitable wetland infill substrate due to its low density, exceptional water absorption capabilities, and high porosity. This study investigated, for the first time, the use of construction demolition wastes (CDW), and rock processing residues (RPR) as substrate materials in vertical-horizontal flow hybrid constructed wetlands for the treatment of cheese production wastewater. Results showed that the use of both CDW as well as RPR, as substrate material, provided an equal or even better quality of treated wastewater compared to the conventional use of gravel as a substrate. High removal efficiencies were recorded for turbidity (CDW: 91-92%, RPR: 97%), solids (CDW: 85-88%, RPR: 96-97%), organic matter (CDW: 79-84%, RPR: 96-98%), and total phosphorus (CDW: 72-76%, RPR: 87%) for both examined recycled materials. During the experiment, different loadings rates (HLR) were tested: 25 mm d -1 and 37.5 mm d -1 . Radiological measurements indicate that, their use did not cause toxic effects on the environment, as the amounts of radioactivity found in the effluent of the systems are not significant. Increasing the hydraulic loading rate appeared to have no negative effect on pollutant removal, as the systems and plants were fully acclimated and mature. This approach offers several advantages, including the use of readily available and abundant waste material, potential cost savings, and the environmental benefits of recycling CDW and RPR instead of disposing of them in landfills., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest regarding the publication of this article., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Wastewater treatment plants (WWTPs) have been recognized as secondary sources of per- and polyfluoroalkyl substances (PFAS) released into the environment. In this study, PFAS concentrations were measured in effluent and biosolids samples collected from 75 WWTPs across Australia during the 2016 Census period, which covers more than half of the Australian population. Twelve PFAS compounds, including six C5-C10 perfluoroalkyl carboxylic acids (PFCAs), four perfluoro sulfonic acids (PFSAs) such as perfluorobutane sulfonate (PFBS), perfuorohexane sulfonic (PFHxS), perfluorooctane sulfonic acid (PFOS), and perfluorodecane sulfonic acid (PFDS), and one fluorotelomer sulfonic acid (6:2 FTS), were detected in the effluent, with concentrations up to 504 ng/L (PFHxS). Among these, perfluorooctanoic acid (PFOA), perfluorohexanoic acid (PFHxA), and perfluoropentanic acid (PFPeA) exhibited the highest median concentrations. In the biosolids, a total of 21 PFAS compounds were detected, encompassing ten C4-C14 PFCAs, four PFSAs, two FTS (6:2 and 8:2 FTS), perfluorooctane sulfonamide (PFOSA), two perfluorooctane sulfonamido acetic acid (NMethyl FOSAA and NEthyl FOSAA), and two perfluorooctane sulfonamido ethanol (FOSE), with dry weight (dw) concentrations approaching 235 ng/g (PFOS). The highest median and mean concentrations were observed for perfluorodecanoic acid (PFDA) and PFOS. An annual discharge of approximately 250 kg of the total 21 PFAS compounds was estimated through the effluent and biosolids of the participating WWTPs. Notably, PFOS and 6:2 FTS constituted the largest proportion of total PFAS in the WWTPs' output. While PFCAs were higher in effluent concentrations compared to influent levels across most WWTPs (92% of WWTPs for ∑ 8 PFCAs), the concentrations of PFSAs either decreased or remained relatively stable (in 80% of WWTPs for ∑ 4 PFSAs) throughout the wastewater treatment process., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Eutrophication can impact bacteria by altering fluxes and processing of nutrients and organic matter. However, relatively little is known of how bacterial communities, diversity, and interactions with phytoplankton might respond to nutrient management. We used 16S rRNA amplicon sequencing to compare bacterial assemblages in the water column upstream (control) and downstream (impact) of a wastewater treatment plant (WWTP) located on a eutrophic prairie stream. Sampling occurred before (2012) and after (2018) the 2016 biological nutrient removal (BNR) upgrade that removed >90% of nitrogen (N, mainly NH4+). Multivariate ordination suggested that effluent-impacted bacterial communities were associated mainly with elevated NH4+ concentrations before the upgrade, whereas those after BNR were characteristic of reference systems (low NO3-, diverse regulation). Genera such as Betaproteobacteria and Rhodocyclacea were abundant at impacted sites in 2012, whereas Flavobacterium and a potential pathogen (Legionella) were common at impacted sites in 2018. Nitrifier bacteria (Nitrospira and Nitrosomonas) were present but rare at all sites in 2012, but recorded only downstream of the WWTP in 2018. Generalized additive models showed that BNR reduced bacterial diversity, with ∼70% of the deviance in diversity explained by hydrology, pH, nutrients, and phytoplankton abundance. Overall, NH4+ removal reduced symptoms of cultural eutrophication in microbe assemblages., (© The Author(s) 2023. Published by Oxford University Press on behalf of FEMS.)

Oils and grease (O&G) have low affinity for water and represent a class of pollutants present in the dairy industry. Enzyme-mediated bioremediation using biocatalysts, such as lipases, has shown promising potential in biotechnology, as they are versatile catalysts with high enantioselectivity and regioselectivity and easy availability, being considered a clean technology (white biotechnology). Specially in the treatment of effluents from dairy industries, these enzymes are of particular importance as they specifically hydrolyze O&G. In this context, the objective of this work is to prospect filamentous fungi with the ability to synthesize lipases for application in a high-fat dairy wastewater environment. We identified and characterized the fungal species Aspergillus sclerotiorum as a good lipase producer. Specifically, we observed highest lipolytic activity (20.72 U g -1 ) after 96 h of fermentation using sunflower seed as substrate. The fungal solid fermented was used in the bioremediation in dairy effluent to reduce O&G. The experiment was done in kinetic from 24 to 168 h and reduced over 90% of the O&G present in the sample after 168 h. Collectively, our work demonstrated the efficiency and applicability of fungal fermented solids in bioremediation and how this process can contribute to a more sustainable wastewater pretreatment, reducing the generation of effluents produced by dairy industries., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The conventional electrode aluminum used in electrocoagulation (EC) for the textile wastewater undergoes pitting type of corrosion, so dissolution of the same is very high during electrolysis. This research focuses on the treatment of real-time textile effluent with copper electrodes that corrode uniformly during electrolysis, with optimizing operating parameters for high color removal efficiency (CRE%). The sludge acquired was analyzed by XPS and XRD to study the mechanism of dye removal. The treated effluent was subjected to phytotoxicity analysis using Vigna radiata to study the toxicity effect of the intermediary products. 98.6% of CRE was attained in treating the effluent with copper electrodes. XPS and XRD results showed that both Cu(OH) 2 and CuO served as coagulants in the dye removal. The phytotoxicity results showed that the percentage of germination, shoot and root lengths of Vigna radiata in the treated effluent were similar to the results obtained for the control.

Thiocyanate is a common pollutant in gold mine, textile, printing, dyeing, coking and other industries. Therefore, thiocyanate in industrial wastewater is an urgent problem to be solved. This paper reviews the chemical properties, applications, sources and toxicity of thiocyanate, as well as the various treatment methods for thiocyanate in wastewater and their advantages and disadvantages. It is emphasized that biological systems, ranging from laboratory to full-scale, are able to successfully remove thiocyanate from factories. Thiocyanate-degrading microorganisms degrade thiocyanate in autotrophic manner for energy, while other biodegrading microorganisms use thiocyanate as a carbon or nitrogen source, and the biochemical pathways and enzymes involved in thiocyanate metabolism by different bacteria are discussed in detail. In the future, degradation mechanisms should be investigated at the molecular level, with further research aiming to improve the biochemical understanding of thiocyanate metabolism and scaling up thiocyanate degradation technologies from the laboratory to a full-scale., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Agricultural use of treated wastewater (TWW) is an effective means to reduce freshwater (FW) consumption. However, there is a growing concern regarding the potential dissemination of antibiotic resistance elements by TWW irrigation. We hypothesized that higher levels of antibiotic resistance genes (ARGs) would be detected in soil and crops irrigated with TWW compared to FW irrigation. To test our prediction, samples of water (FW, secondary TWW, and tertiary TWW), irrigated soils, and crops (tomato) surface wash were collected during two consecutive growing seasons. The ARGs conferring resistance to sulfonamide, fluoroquinolone, penicillin, erythromycin and tetracycline were quantified in the samples, alongside Class 1 integron-integrase and the bacterial 16 S rRNA encoding genes. Contrary to our hypothesis, ARGs in the irrigation water were not propagated to either the irrigated soil, or the tomato. The tomato surface wash featured a variety of ARGs that were undetected in neither the waters nor the irrigated soils. Therefore, we cautiously question the link between irrigation water quality and the soil and produce resistomes., (Copyright © 2022. Published by Elsevier Inc.)

Objectives: The resistome, virulome, mobilome and phylogenetic relationship of the Acinetobacter baumannii isolate FG121 depicting the multilocus sequence type (ST) 231 isolated from hospital effluent water in South Africa was determined using whole-genome sequence analysis., Method: A. baumannii FG121 was isolated on Leed Acinetobacter Medium (LAM) agar and the bacterial isolate was identified using the VITEK®2 platform. Antibiotic susceptibility testing was performed using Kirby-Bauer Disk diffusion method. A whole genome sequencing library was constructed from DNA extracted from the isolate using the Illumina Nextera XT library preparation kit and was sequenced using the Illumina NextSeq500 platform. Generated reads were de novo assembled using SpAdes v.3.9. The assembled contigs were annotated, and multilocus sequence type, antimicrobial resistance, and virulence genes were identified., Results: The resistome was consistent with the resistance phenotype of the isolate with resistance determinants for beta-lactams, aminoglycosides, and tetracycline (bla ADC-25 , bla OXA-23 , bla OXA-51 , bla NDM-1 , aph[3']-VIa and tet[B]). Global phylogenomic analysis using BacWGSTdb revealed that the isolate belonged to the multilocus sequence type ST-231, similar to previously reported isolates from South Africa, the United States, and related to the invasive KR3831 isolate identified from Oman in 2012, suggesting the isolate might be imported from abroad. Virulome analysis predicted both virulence and biofilm-determinants of A. baumannii, which may help to establish infections in adverse conditions., Conclusion: This is the first report on a carbapenemase-encoding A. baumannii ST-231 isolated from hospital effluent water. Our data will offer insight into the global phylogenetic, pathogenicity and distribution of A. baumannii in South Africa., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The spread of antibiotic-resistant bacteria (ARB) associated with wastewater is a significant environmental concern, but little is known about the persistence and proliferation of these organisms in receiving water bodies after discharge. To address this knowledge gap, we performed a series of microcosm experiments in which river water was amended with either untreated or treated wastewater, and the abundance of viable ciprofloxacin-, Bactrim-, and erythromycin-resistant bacteria was monitored for 72 h. Both types of wastewater amendments significantly increased the initial abundance of ARB compared to microcosms containing only river water (all p < 0.03). The increase was greatest with untreated wastewater, but that effect decreased steadily over time. In contrast, microcosms amended with treated wastewater saw a smaller initial increase and more complex temporal dynamics. Following a brief lag, ARB abundance bloomed for all three of the antibiotics that we considered. This suggests that ARB that survive wastewater treatment are particularly hardy and may proliferate in riverine conditions after a short recovery period. To determine how interactions with the native river microbial community impacted the persistence of wastewater-associated ARB, an additional set of microcosms was prepared using filter-sterilized river water. Peak abundance in these microcosms was significantly higher by 1-2 orders of magnitude compared to microcosms containing an intact river microbial community (all p < 0.05), which suggests that biotic interactions play a significant role in regulating the persistence and proliferation of ARB. The data presented in this paper are among the first available that specifically consider persistence of viable ARB and represent an important step toward understanding AR-related human health risks downstream from wastewater discharge points and following sewer overflow events. Additional studies that consider longer time scales and the interplay of biotic and abiotic variables are essential for modeling public health risks associated with wastewater inputs of ARB to rivers and other aquatic environments., Competing Interests: Declaration of competing interest The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Effluents of textile industries caused serious environmental problem throughout the world. In this study, a total of 23 bacterial strains from five bacterial species were isolated from the dye effluent. Of these strains, a unique and novel Enterobacter aerogenes ES014 was utilized for dye decolourization and toxicity analysis. The selected strain could effectively decolourize three selected azo dyes. It showed the capability for decolourizing acid orange (82.3 ± 3.6%), methyl orange (78.2 ± 3.3%), and congo red (81.5 ± 3.2%). The selected bacterial strain significantly decolourized 100 mg/L acid orange at 35 °C, pH 7.5 with 6% sodium chloride concentration. Most of the tested nitrogen and carbon sources effectively enhanced decolourization process. It showed the ability to decolourize acid orange in the culture medium containing 1.5% glucose (100 ± 2.8%) and 0.8% beef extract (100 ± 3.1%). A laboratory-scale batch bioreactor was used to decolourize azo dye at optimized culture conditions. The decolourizing ability improved with 100 mL/h hydraulic retention time. The treated wastewater quality was improved due to sharp depletion of Total Dissolved Solids (TDS), pH, Chemical Oxygen Demand (COD), alkalinity and sulphate concentration. The selected bacteria has the potential to produce dye degrading laccase. Laccase was detected during fermentation process in batch bioreactor as a key enzyme for decolourization produced by E. aerogenes ES014. Phytotoxicity and acute toxicity analysis were performed using Arachis hypogaea (pea nut) seed and first instar larvae of Artemia parthenogenetica (brine shrimp). The seed germination rate of treated wastewater was improved (94.3 ± 1.8%) and enhanced survival rate (91.7 ± 2.9%) in the first instar Artemia larvae treated with wastewater after 24 h. Overall, E. aerogenes ES014, might be a promising bacterial strain for the treatment of textile effluents with high azo dye concentrations., (Copyright © 2021. Published by Elsevier Inc.)

Bioremediation is an essential feature of microorganisms concerning contaminations in soil and water. The use of microorganisms has been proved to be an effective treatment of industrially released effluents comprising of heavy metals, such as chromium (VI). In the current study, seasonal variations were observed in the concentrations of chromium(VI) as the samples from selected locations showed an increase in mean concentration during the summer compared to the low mean during winter, suggesting excessive evaporation in the summer leading to the heavy metal accumulation. Among the 35 isolates obtained from tannery effluent contaminated wastewater sources the 3 unique strains identified as Streptococcus pyogenes strain APRRJVITS10, Pseudomonas putida strain APRRJVITS11, and Bacillus thuringiensis strain APRRJVITS15, showed tolerance toward chromium(VI) and the maximum tolerance for each strain was 1250 ppm. The media optimization through shake flask methods showed chromium(VI) (in 100 ml LB broth) removal of 47.82%, 48.11%, and 49.93% by S. pyogenes , P. putida, and B. thuringiensis respectively. Further, Pseudomonas putida showed chromium(VI) (in 1500 ml LB broth) removal of 50.48% in optimized conditions, proving to be highly potential for treating effluent wastewater for chromium(VI) removal.

In the last two decades, water use has increased at twice the rate of population growth. The freshwater resources are getting polluted by contaminants like heavy metals, pesticides, hydrocarbons, organic waste, pathogens, fertilizers, and emerging pollutants. Globally more than 80% of the wastewater is released into the environment without proper treatment. Rapid industrialization has a dramatic effect on developing countries leading to significant losses to economic and health well-being in terms of toxicological impacts on humans and the environment through air, water, and soil pollution. This article provides an overview of physical, chemical, and biological processes to remove wastewater contaminants. A physical and/or chemical technique alone appears ineffective for recovering useful resources from wastewater containing complex components. There is a requirement for more processes or processes combined with membrane and biological processes to enhance operational efficiency and quality. More processes or those that are combined with biological and membrane-based processes are required to enhance operational efficiencies and quality. This paper intends to provide an exhaustive review of electrochemical technologies including microbial electrochemical technologies. It provides comprehensive information for the recovery of metals, nutrients, sulfur, hydrogen, and heat from industrial effluents. This article aims to give detailed information into the advancements in electrochemical processes to energy use, improve restoration performance, and achieve commercialization. It also covers bottlenecks and perspectives of this research area.

Diminishing freshwater (FW) supplies necessitate the reuse of treated wastewater (TWW) for various purposes, like irrigation of agricultural lands. However, there is a growing concern that irrigation with TWW may transfer antibiotic resistance genes (ARGs) to the soil and crops. We hypothesized that TWW irrigation would increase the prevalence of antibiotic residues together with the corresponding ARGs in the irrigated soil. We further predicted that soil texture, especially pH, clay content, and organic matter variabilities, would change the antibiotic residues concentrations and thus ARGs dissemination. To test our predictions, three soils types (loamy-sand, loam, and clay) were irrigated with two water types (FW and TWW), over two consecutive seasons. We monitored physico-chemical parameters, the abundance of seven antibiotic residues, and their corresponding ARGs together with class 1 integron (intI1) in 54 water and soil samples collected at the end of the field experiments. The results revealed increase in antibiotics concentrations and ARGs relative abundance in TWW than FW. Yet, in the soil ARGs relative abundances were independent of the irrigation water quality, but dependent on the soil type, especially the clay content. Further, there were no clear associations between the targeted antibiotics or the presence of heavy metals and ARGs' relative abundance in the water or soil samples. Therefore, our results question the link between the discharge of antibiotics and heavy metals, and the dissemination of ARGs in soil environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Constructed wetlands (CWs) are a potential solution for wastewater treatment due to their capacity to support native species and provide tertiary wastewater treatment. However, CWs can expose wildlife communities to excess nutrients and harmful contaminants, affecting their development, morphology, and behavior. To examine how wastewater CWs may affect wildlife, we raised Southern leopard frogs, Lithobates sphenocephalus, in wastewater from conventional secondary lagoon and tertiary CW treatments for comparison with pondwater along with the presence and absence of a common plant invader to these systems - common duckweed (Lemna minor) - and monitored their juvenile development for potential carryover effects into the terrestrial environment. The tertiary CW treatment did not change demographic or morphological outcomes relative to conventional wastewater treatment in our study. Individuals emerging from both wastewater treatments demonstrated lower terrestrial survival rates than those emerging from pondwater throughout the experiment though experiment-wide survival rates were equivalent among treatments. Individuals from wastewater treatments transformed at larger sizes relative to those in pondwater, but this advantage was minimized in the terrestrial environment. Individuals that developed with duckweed had consistent but marginally better performance in both environments. Our results suggest a potential trade-off between short-term benefits of development in treated effluent and long-term consequences on overall fitness. Overall, we demonstrate that CWs for the purpose of wastewater treatment may not be suitable replicates for wildlife habitat and could have consequences for local population dynamics., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Environmental dissemination of antimicrobial resistance is a global health problem. Antimicrobial-resistant bacteria and antibiotic-resistant genes (ARGs) are constantly released into the environment through effluents (EFs) from wastewater treatment plants (WWTPs). Thus, requiring a better understanding of the selection and fate of ARGs in wastewater treatment processes. Therefore, we investigated the impacts of urban WWTP EFs on receiving water in the context of their resistomes and mobilomes. We used a HiSeq-based short read metagenomic approach to address the dynamics and diversity of ARGs in WWTP EF as well as the upstream (UP) and downstream (DN) river waters, followed by an investigation of plasmid-mediated ARGs. The abundance of ARGs at each site varied from 7.2 × 10 -2 to 7.4 × 10 -1 ARG copies per 16S rRNA gene copy, and EF samples showed the highest abundance, followed by DN and UP water samples. ARG diversity ranged from 121 to 686 types per site, and EF had the most diverse ARGs. Commonly identified ARGs in the EF and DN samples were clinically important and were absent in UP samples. The abundance of ARGs, mobile genetic elements (MGEs), and plasmid contigs found only in EF and DN were positively correlated with each other, indicating the importance of mobilomes in the dissemination of ARGs in the environment. Moreover, the proportions of plasmid-mediated ARGs was highest in the EF samples, followed by the DN and UP samples. These findings suggest that WWTP EF may act as a driving factor shaping the resistomes and mobilomes of receiving waters. In particular, a higher abundance of plasmid-mediated ARGs in WWTP EF suggests higher transmissibility in the DN environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Wastewater-treatment plants (WWTPs) are an important source of mercury (Hg) to surface waters, but little is known about temporal variability of efflux to aquatic systems. We found that Hg concentrations in effluent varied by about a factor of 2 on monthly, weekly, and hourly timescale comparisons. These results suggest that limited sampling can yield a representative concentration with reasonable uncertainty for purposes of estimating the environmental significance of Hg from WWTPs. Environ Toxicol Chem 2020;39:1027-1031. © 2020 SETAC., (© 2020 SETAC.)

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of Editors-in-Chief and first Author. The article duplicates significant parts of a paper that had already appeared in Fish & Shellfish Immunology, Volume 93 (2019) 726-731, https://doi.org/10.1016/j.fsi.2019.06.052. One of the conditions of submission of a paper for publication is that authors declare explicitly that the paper has not been previously published and is not under consideration for publication elsewhere. As such this article represents a misuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process. The first author informed the journal that the article was published without the knowledge of the co-authors., (Copyright © 2019. Published by Elsevier Ltd.)

In this study, the effects of Rhodopseudomonas capsulata present in wastewater effluent on the biodegradation of carbaryl in soil and improvement of soil fertility were investigated. Compared to control treatment, carbaryl was removed efficiently and soil fertility was remediated with the addition of effluent containing R. capsulata. Molecular analysis revealed that carbaryl induced carbaryl hydrolase gene expression to synthesize carbaryl hydrolase through activating MAPKKKs, MAPKKs, MAPKs genes in MAPK signal transduction pathway. The induction and secretion of carbaryl hydrolase occur after one day in R. capsulata, which can be attributed to its characteristics as an ancient bacteria, which require acclimatization to carbaryl before gene induction. However, lack of organics in soil and control treatment could not maintain R. capsulata growth for over one day. The residual organics in the effluent provided sufficient carbon source and energy for R. capsulata under four effluent treatments. This new method resulted in the remediation of carbaryl pollution and improvement of soil fertility and soybean processing wastewater treatment simultaneously, as well as the reutilization of wastewater and R. capsulata as sludge. Meanwhile, the high-order non-linear mathematical model about carbaryl removal rate was established., (Copyright © 2019. Published by Elsevier Ltd.)

Antibiotic resistance genes (ARGs) have been regarded as an emerging pollutant in municipal wastewater treatment plant (WWTP) effluents due to their potential risk to human health and ecological safety when reused for landscape and irrigation. Conventional wastewater treatment processes generally fail to effectively reduce ARGs, especially extracellular ARGs (eARGs), which are persistent in the environment and play an important role in horizontal gene transfer via transformation. Herein, an integrated process of pre-coagulation and microfiltration was developed for removal of ARGs, especially eARGs, from wastewater effluent. Results show that the integrated process could effectively reduce the absolute abundances of total ARGs (tARGs) (>2.9 logs) and eARGs (>5.2 logs) from the effluent. The excellent performance could be mainly attributed to the capture of antibiotic resistant bacteria (ARB) and eARGs by pre-coagulation and co-rejection during subsequent microfiltration. Moreover, the integrated process exhibited a good performance on removing common pollutants (e.g., dissolved organic carbon and phosphate) from the effluent to improve water quality. Besides, the integrated process also greatly reduced membrane fouling compared with microfiltration. These findings suggest that the integrated process of pre-coagulation and microfiltration is a promising advanced wastewater treatment technology for ARGs (especially eARGs) removal from WWTP effluents to ensure water reuse security., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Pharmaceutical and personal care product compounds (PPCPs) comprise a large and diverse group of chemical compounds, including prescription and over-the-counter drugs and cleaning agents. Although PPCPs in the effluent and biosolids of water resource recovery facilities (WRRFs) are currently not regulated, public interest has led the Metropolitan Water Reclamation District of Greater Chicago to monitor for 11 PPCPs in the influent, effluent, and biosolids at its seven WRRFs. In 2016, the U.S. Food and Drug Administration (FDA) issued a final rule establishing that 19 specific ingredients, including triclosan and triclocarban, were no longer generally recognized as safe and effective, which prohibits companies from marketing soaps as antibacterial if they contain one or more of these ingredients. It was presumed that since the proposed rulemaking in 2013, manufacturers began to remove these active ingredients from their products. Annual monitoring of 11 PPCPs from 2012 to 2017 demonstrated a 71% decrease in triclosan and 72% decrease in triclocarban in per capita influent loading into seven WRRFs. There was a 70% decrease in triclosan and 80% decrease in triclocarban concentrations in biosolids. These declines suggest the FDA rule for the reduction in use of these compounds was effective and resulted in manufacturers removing these ingredients from their products. PRACTITIONER POINTS: Reduction in triclosan and triclocarban per capita influent loading observed from 2012 to 2017. Reduction in triclosan and triclocarban biosolids loading observed from 2012 to 2017. 2016 FDA rulemaking on antimicrobial soaps was effective in removing triclosan and triclocarban from these products. Positive impact on quality of biosolids land applied to farmland., (© 2019 Water Environment Federation.)

The analytical capability of the UPLC-Q Exactive™ Orbitrap MS was exploited for simultaneous determination of 30 acidic and basic PPCPs in a single run, using rapid polarity switching of the electrospray ionisation source. Full scan MS mode at resolution of 35,000 FWHM, Automatic gain control (AGC) target of 1E6 ions at injection time of 50 ms provided the optimum parameters for high sensitivity, together with sufficient data points per peak (≥15) for improved reproducibility. In addition to chromatographic retention times, method selectivity was achieved via applying high resolution accurate mass with low mass tolerance filter (<5 ppm) for identification of each target compound. Six-point linear calibration curves (R 2 > 0.95) were established for all target analytes over a concentration range of 1-1500 ng/ml. Good results were obtained for method accuracy (% recovery = 76-104%), inter- and intra-day precision (relative standard deviation <15%) at 3 concentration levels. Instrumental detection and quantification limits ranged from (0.02-1.21 ng/ml) and (0.07-4.05 ng/ml), respectively. While optimised MS/MS analysis through parallel reaction monitoring (PRM) mode provided slightly higher sensitivity, Full scan MS mode allowed for higher mass resolution (selectivity), more data points per peak (reproducibility) and more importantly, the potential for post-acquisition screening of non-target compounds. Following solid phase extraction (SPE) of target analytes, the method was successfully applied to provide first data on PPCPs occurrence in effluent and surface water samples (n = 10) from Egypt. Moreover, screening for non-target compounds revealed the presence of bisphenol A, which was further confirmed via matching with an authentic standard. Overall, this study provides first insight into the high analytical capabilities of the Q-Exactive™ Orbitrap platform for both targeted/non-targeted analysis of PPCPs in environmental matrices., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Natural adsorbent was optimized from four natural adsorption materials (kaolin, bentonite, diatomite, and natural zeolite) through the comparison of their ability to recover organic matter from an ultra-short-sludge-retention-time (ultra-short-SRT) activated sludge process effluent. Natural zeolite was modified by the loading of three types of chemical coagulants (Fe 2 (SO 4 ) 3 , Al 2 (SO 4 ) 3 , and ZnSO 4 ) and was used for the study of the advanced recovery of organic matter. The results of Brunauer-Emmett-Teller surface area (S BET ) measurements, scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses showed that natural zeolite was successfully modified, with decrease in the specific surface area of the modified zeolite (MZ), but some metal ions/metal oxides were loaded onto the surface of natural zeolite. Compared with chemical coagulant and natural zeolite, the organic recovery efficiency from the effluent of the MZs improved, and after the optimization process, the organic recovery efficiency of MZ4 (Zeolite:Fe 2 (SO 4 ) 3  = 4:1), MZ9 (Zeolite:Al 2 (SO 4 ) 3  = 4:1), and MZ13 (Zeolite:ZnSO 4  = 2:1) reached 72.0%, 67.6%, and 61.2%, respectively. The MZs can allow a significant amount of recovery of soluble chemical oxygen demand (SCOD) from the effluent, with SCOD recovery efficiencies for MZ4, MZ9, and MZ13 of 44.8%, 44.3%, and 39.4%, respectively. The E 4 /E 6 , UV 253 /UV 203 , and SUVA analyses after the organic recovery experiments indicated that the generation potential of disinfecting byproducts or halogenated products was reduced in the treated effluent by the MZs. The mechanism can be considered in two ways: the coagulation effect of the loaded metal ions/metal oxides and the physical and chemical adsorption effect based on the hydrogen bond and ππ bond between the MZ and organic matter. This study facilitated the application of organic recovery from wastewater and the advanced treatment of effluent., (Copyright © 2018 Elsevier B.V. All rights reserved.)

There is little known about the wastewater treatment plant (WWTP) effluent microbiome, its structure and dynamics. Here, we provide a study of the microbiome of effluent leaving conventional WWTPs and entering the water environment. DNA was extracted from WWTP effluent samples collected in 2015 and 2016. The bacterial communities were studied using Illumina MiSeq 16S rRNA gene amplicon sequencing and analysed using Calypso software. The Proteobacteria, Bacteroides, Actinobacteria, Firmicutes, Tenericutes and Verrucomicrobia phyla dominated the microbiomes. The bacterial community composition at high taxonomic levels is consistent between the tested WWTP effluents, and in agreement with previous studies of WWTP effluents in different global locations. The analysed microbiomes of the WWTPs shared high similarities with human faecal microbiome and contained potential human pathogens. The bacterial phyla/class composition of the bacterial communities varied greatly in both WWTP effluents in October 2015. The bacterial diversity was slightly different between studied WWTPs. Two main bacterial clusters were detected in all samples during all sampling periods. In conclusion, this work highlights the need for a better understanding of the bacterial communities in WWTP effluent. This data should be considered when analysing the risk posed by WWTP effluent to the environment and to human health., (© FEMS 2019.)

Wastewater contains a large range of biological and chemical markers of human activity and exposures. Through systematic collection and analysis of these markers within wastewater samples it is possible to measure the public health of whole populations. The analysis of effluent and biosolids can also be used to understand the release of chemicals from wastewater treatment plants into the environment. Wastewater analysis and comparison with catchment specific data (e.g. demographics) however remains largely unexplored. This manuscript describes a national wastewater monitoring study that combines influent, effluent and biosolids sampling with the Australian Census. An archiving program allows estimation of per capita exposure to and consumption of chemicals, public health information, as well as per capita release of chemicals into the environment. The paper discusses the study concept, critical steps in setting up a coordinated national approach and key logistical and other considerations with a focus on lessons learnt and future applications. The unique combination of archived samples, analytical data and associated census-derived population data will provide a baseline dataset that has wide and potentially increasing applications across many disciplines that include public health, epidemiology, criminology, toxicology and sociology., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Floating treatment wetlands (FTWs) are an innovative product of ecological engineering that can play a promising role in wastewater treatment. It provides low-cost, eco-friendly, and sustainable solutions for the treatment of wastewater, particularly in regions with economic constraints. Generally, FTWs comprise rooted plants that grow on the surface of water with their roots extending down into the pelagic zone rather than being embedded into the sediments. This drooping structure helps develop (1) a hydraulic flow between the root network and the bottom of the treatment system and (2) a large biologically active surface area for the physical entrapment (filtration) of contaminants, as well as their biochemical transformation and degradation. Furthermore, the rooted network allows proliferation of microorganisms that form biofilms and enhance pollutant degradation while promoting plant growth. The augmentation of bacteria in FTWs has been proven to be the most effective approach for reclamation of wastewater. This article discusses the operational parameters of FTWs for maximal remediation of wastewater and highlights the importance of plant-bacteria partnerships in a typical FTW system for enhanced cleanup of wastewater. We propose that this technology is preferable over other methods that require high energy, costs, and area to install or operate machinery.

The aim of this study was to evaluate the phytotoxicity of raw and treated effluents from a parboiling rice industry in the south of Brazil. The evaluation included 19 physicochemical parameters and a phytotoxicity test using lettuce and cucumber seeds as bioindicators. The germination index (GI) of both seeds was decreased when in contact with the raw effluent (p < 0.05) and with the treated effluent reduced the GI of cucumber seeds (p < 0.05) and the root length (RL) of lettuce seeds (p < 0.05). For lettuce seeds exposed to the treated effluent there was a negative correlation (p < 0.05) between RL and Mn (- 0.82) and between GI and Fe (- 0.68). For cucumber seeds in the raw effluent, the Fe showed negative correlation (p < 0.05) with seed germination (- 0.75), but, in the treated effluent, their GI presented positive correlation (0.61) with the ammoniacal-N (p < 0.05). The results indicated that both effluents showed phytotoxicity for lettuce and cucumber seeds.

We evaluated the effects of wastewater effluents on pale chub (Zacco platypus) in a contaminated stream by integrating genotoxic, oxidative stress, histological, and physiological biomarkers. The metal pollution index indicated higher pollution loads at downstream sites (DS1 and DS2) compared with the upstream reference site. Significantly higher nuclear abnormality confirmed the existence of genotoxicity (p < 0.05) at downstream sites. Antioxidant activity (catalase and glutathione S-transferase) and lipid peroxidation levels in livers of Z. platypus were also significantly higher at the DS1 site (p < 0.05). The liver somatic index was also influenced, with abnormal histological alterations in the liver, possibly caused by heavy metal accumulation (Cd, Co, Cr, Mn, Ni, and Pb). The integrated biomarker response value was the highest at DS1 (13.74) followed by DS2 (1.94), indicating that wastewater effluents had the potential to cause adverse effects on Z. platypus inhabiting receiving stream.

Discharges from pharmaceutical manufacturing facilities (PMFs) previously have been identified as important sources of pharmaceuticals to the environment. Yet few studies are available to establish the influence of PMFs on the pharmaceutical source contribution to wastewater treatment plants (WWTPs) and waterways at the national scale. Consequently, a national network of 13 WWTPs receiving PMF discharges, six WWTPs with no PMF input, and one WWTP that transitioned through a PMF closure were selected from across the United States to assess the influence of PMF inputs on pharmaceutical loading to WWTPs. Effluent samples were analyzed for 120 pharmaceuticals and pharmaceutical degradates. Of these, 33 pharmaceuticals had concentrations substantially higher in PMF-influenced effluent (maximum 555,000 ng/L) compared to effluent from control sites (maximum 175 ng/L). Concentrations in WWTP receiving PMF input are variable, as discharges from PMFs are episodic, indicating that production activities can vary substantially over relatively short (several months) periods and have the potential to rapidly transition to other pharmaceutical products. Results show that PMFs are an important, national-scale source of pharmaceuticals to the environment., (Published by Elsevier B.V.)

The effluents of wastewater treatment plants (WWTPs) are the important sources for pollutants. These pollutants may entry into surface water, groundwater, and soil by recharging and irrigation then pose risk to human beings. Using reports from the past 20 years (n = 58), we conducted this review of organic contaminants (OCs) in the effluent of Chinese WWTPs. All the studies were during 2005 to 2017 and more than two papers were conducted in every year. Nineteen provinces (20 cities) were covered and most of the studies were located in the eastern part of China, especially the most developed and highest density of population areas. Two hundred eighty-four OCs were contained. E antibiotics, endocrine-disrupting chemicals (EDCs), and pharmaceuticals were the most commonly studied groups of OCs, and ofloxacin, norfloxacin, and sulfamethoxazole were the three most commonly reported OCs. The highest concentration appeared for bisphenol A (BPA). The relative standard deviations (RSDs) of concentrations of the most commonly studied compounds were high. In the future, more studies should pay attention on national analysis and more pollutants.

Marine pollution by plastics and microplastics (plastic particles 1 nm to 5 mm) is a recognized environmental issue. There are a few studies measuring the concentration of microplastics in the wastewater treatment plants (WWTP) effluent to the sea. Although microplastic concentrations are low in the WWTP effluent, the actual amount of microplastic ending up in the marine environment through WWTPs is quite significant. The present study is an extensive questionnaire-based survey to untrained managers of 101 WWTPs located all over Greece reporting visually-observed plastic items. 94 of the WWTPs have screens with gaps larger than 5 mm. This suggests that microplastics are passing through pretreatment to the main WWTP. In addition, 89 of the WWTP managers observed plastics in different tanks of the WWTPs. Cotton swab sticks are identified as the most common plastic found in WWTPs and the surrounding marine and coastal areas of the effluent pipes., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This study evaluated the adverse effect of wastewater effluents on three fish species, Carassius auratus, Zacco platypus, and Zacco koreanus, collected in the Eungcheon, Mihocheon, and Busocheon streams, respectively. Fish gills, liver, and kidneys from the mixing zone (MZ) and sites upstream (US) and downstream (DS) of the MZ were analyzed for oxidative stress responses and histology. Catalase and glutathione S-transferase activity was significantly higher at MZ and DS than from US (p<0.05), indicating induction of antioxidant defense mechanisms. Additionally, degree of tissue changes (DTC) indicated highest histopathological alteration in MZ, followed by DS and US. Integrated biomarker response (IBR) for oxidative stress and histopathological alterations showed higher values consistently for Z. koreanus than other two species. Water temperature, EC, and TN levels seemed to be responsible for the observed biomarker responses. These findings indicate that thermal hot spring effluent discharged into Busocheon steam induced the most significant impact on the cool water species (Z. koreanus). Overall, this study suggests that the IBR index is a very useful tool for monitoring in situ adverse effects of wastewater effluents on fish, particularly for histopathological alterations representing prolonged impact., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This work reports on the variation in wastewater treatment works (WwTW) influent concentrations of a wide variety of active pharmaceutical ingredients (APIs), their removal efficiency, effluent concentrations and potential risks to the aquatic environment. The research is based on data generated from two large UK-wide WwTW monitoring programmes. Taking account of removal of parent compound from the aqueous phase during treatment in combination with estimates of dilution available it is possible to prioritise the APIs of greatest risk of exceeding estimates of predicted no effect concentrations (PNEC) in receiving waters for all WwTW in the UK. The majority of substances studied were removed to a high degree, although with significant variation, both within and between WwTW. Poorer removal (between influent and effluent) was observed for ethinyloestradiol, diclofenac, propranolol, the macrolide antibiotics, fluoxetine, tamoxifen and carbamazepine. All except the last two of these substances were present in effluents at concentrations higher than their respective estimated PNEC (based on measurement of effluents from 45 WwTW on 20 occasions). Based on available dilution data as many as 890 WwTW in the UK (approximately 13% of all WwTW) may cause exceedances of estimated riverine PNECs after mixing of their effluents with receiving waters. The overall degree of risk is driven by the toxicity value selected, which in itself is controlled by the availability of reliable and relevant ecotoxicological data and consequently the safety factors applied. The dataset and discussion, provides information to assist in the future management of these types of chemicals., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In this study, the estrogenicity of two major wastewater treatment plant (WWTP) effluents located in the central reaches of the Grand River watershed in southern Ontario was estimated using population demographics, excretion rates, and treatment plant-specific removals. Due to the lack of data on estrogen concentrations from direct measurements at WWTPs, the treatment efficiencies through the plants were estimated using the information obtained from an effects-directed analysis. The results show that this approach could effectively estimate the estrogenicity of WWTP effluents, both before and after major infrastructure upgrades were made at the Kitchener WWTP. The model was then applied to several possible future scenarios including population growth and river low flow conditions. The scenario analyses showed that post-upgrade operation of the Kitchener WWTP will not release highly estrogenic effluent under the 2041 projected population increase (36%) or summer low flows. Similarly, the Waterloo WWTP treatment operation is also expected to improve once the upgrades have been fully implemented and is expected to effectively treat estrogens even under extreme scenarios of population growth and river flows. The developed model may be employed to support decision making on wastewater management strategies designed for environmental protection, especially on reducing the endocrine effects in fish exposed to WWTP effluents., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Agricultural reuse of wastewater is a common practice worldwide, especially in arid and semiarid area due to the freshwater scarcity. Wastewater irrigation in the Middle East, one of the most water-stressed regions in the world, could be a key factor for socio-economic development, but the microbial contamination of untreated or partially treated wastewater is a serious public health concern. Potential transmission of enteric viral infections through wastewater reuse in agricultural activities represents a true health risk for exposed individuals. Accordingly, it is important to assess the health risks associated with wastewater reuse. A quantitative microbial risk assessment (QMRA) with Monte-Carlo simulation was used to estimate the annual risk of enterovirus (EV) infection and disease burden for farmers and consumers of wastewater-irrigated lettuce in Iran, a semiarid country in the Middle East region. Risk analysis was performed based on the measured concentrations of EV in effluent of two activated sludge wastewater treatment plants (WWTP). Wastewater effluent sampling was carried out over a nine-month period, and the presence of total and fecal coliforms and EV was determined. Fecal coliform bacteria were found at a high level exceeded the guideline limit for wastewater reuse in agriculture. EVs were detected in 40% of samples with the highest frequency in summer with a mean of 12 and 16 pfu/ml for WWTP-A and B, respectively. Statistical analysis showed no correlation between the concentration of fecal coliforms and EV. The estimated infection risk for EVs was 8.8 × 10 -1 and 8.2 × 10 -1 per person per year (pppy) for farmers of WWTP-A and -B, respectively which was about 2 log higher than the tolerable infection risk of 2 × 10 -3 pppy. The estimated risk for lettuce consumers exhibited a lower level of infection and disease burden but higher than the guideline limits. The median disease burden for consumption of lettuce irrigated with activated sludge effluents was about 10 -3 Disability Adjusted Life Years (DALY) pppy which exceeded the WHO guideline threshold of 10 -4 DALY pppy. The results of study indicated that the activated sludge effluents require an additional reduction of EVs to achieve the acceptable level of risk for agricultural reuse of wastewater., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Cultivable microbiota presents in a coffee semi-dry processing wastewater treatment plant (WTP) was identified. Thirty-two operational taxonomic units (OTUs) were detected, these being 16 bacteria, 11 yeasts and 4 filamentous fungi. Bacteria dominated the microbial population (11.61 log CFU mL - 1 ), and presented the highest total diversity index when observed in the WTP aerobic stage (Shannon = 1.94 and Simpson = 0.81). The most frequent bacterial species were Enterobacter asburiae, Sphingobacterium griseoflavum, Chryseobacterium bovis, Serratia marcescens, Corynebacterium flavescens, Acetobacter orientalis and Acetobacter indonesiensis; these showed the largest total bacteria populations in the WTP, with approximately 10 log CFU mL - 1 . Yeasts were present at 7 log CFU mL - 1 of viable cells, with Hanseniaspora uvarum, Wickerhamomyces anomalus, Torulaspora delbrueckii, Saturnispora gosingensis, and Kazachstania gamospora being the prevalent species. Filamentous fungi were found at 6 log CFU mL - 1 , with Fusarium oxysporum the most populous species. The identified species have the potential to act as a biological treatment in the WTP, and the application of them for this purpose must be better studied.

The purpose of this study is to evaluate the removal of chemical oxygen demand (COD), turbidity and color of wastewater from a pig slaughterhouse and packing plant through the electrochemical technique and to optimize the ΔV (electric potential difference) and HRT (hydraulic retention time) variables in an electrocoagulation batch reactor using aluminum electrodes. The experimental design used was rotatable central composite design. For turbidity, the values for removal efficiency obtained varied from 92.85% to 99.28%; for color, they varied from 81.34% to 98.93% and for COD, they varied from 58.61% to 81.01%. The best optimized conditions of treatment were at 25 min for the HRT and 25 V for the ΔV, which correspond to electrical current of 1.08 A and a current density of 21.6 mA cm -2 . The aluminum residue varied from 15.254 to 54.291 mg L -1 and the cost of the treatment was US$4.288 m -3 . The novelty of the work was the simultaneous optimization of three response variables using the desirability function applied to the treatment of wastewater from slaughterhouses.

A reliable and accurate method for collection and analysis of octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in wastewater treatment plant influent, effluent and surface waters was developed. Due to the use of cyclic volatile methylsiloxanes (cVMS) in industrial and consumer products including some personal care products, the wastewater stream represents a potential post-use disposal route and cVMS may subsequently enter the environment through wastewater treatment plant effluents. cVMS in the environment has come under increased regulatory scrutiny with regard to their potential for persistence, bioaccumulation and toxicity indicating a need for monitoring programs with reliable analytical methods. The developed method is unique in that it utilizes low density polyethylene (LDPE) to inhibit loss of cVMS during sampling and transport to the laboratory. The samples are then processed with a simple solvent extraction and analyzed by gas chromatography mass spectrometry with stable isotope internal standard calibration. This method utilizes readily available laboratory supplies and requires minimal field processing, reducing contamination potential. Method detection limits of 17 ng/L, 57 ng/L, and 20 ng/L were obtained for D4, D5, and D6, respectively. Additionally a robust quality control program was employed to ensure sample integrity. The method described herein can readily be adopted for use in monitoring studies where the amount of cVMS in water samples will be quantified., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Monitoring effluents from wastewater treatment plants is important to preventing both environmental contamination and the spread of disease. We evaluated the occurrence of human enteric bacteria (faecal coliforms and Escherichia coli) and viruses (rotavirus and enterovirus) in the final effluents of five wastewater treatment plants (WWTPs) in the Eastern Cape of South Africa. Human viruses were recovered from the effluent samples with the adsorption-elution method and detected with singleplex real-time RT-PCR assays. Rotavirus was detected in several effluents samples, but no enterovirus was detected. At WWTP-C, rotavirus titre up to 10 5 genome copies/L was observed and present in 41.7% of the samples. At WWTP-B, the virus was detected in 41.7% of samples, with viral titres up to 10 3 genome copies/L. The virus was detected once at WWTP-E, in 9% of the samples analysed. The viral titres at WWTP-A were below the detection limit in all 25% of the 1.25L samples in which the virus was detected. Rotavirus was not observed at WWTP-D. Faecal coliform bacteria and E. coli were detected in all the WWTPs, but no correlation was established between the enteric bacteria and viruses studied. The occurrence of rotavirus in effluent samples discharged into surface waters highlights the importance of assessing viral contamination in the water sources used for domestic water use., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The current study investigates the impact of recharging of partially treated wastewater through an infiltration basin on the groundwater aquifer quality parameters. A monitoring program supported by a geographic information analysis (GIS) tool was used to conduct this study. Groundwater samples from the entire surrounding boreholes located downstream the infiltration basin, in addition to samples from the recharged wastewater coming from the Beit Lahia wastewater treatment (BLWWTP), were monitored and analysed between 2011 and 2014. The analysis was then compared with the available historical data since 2008. Results revealed a groundwater replenishment with the groundwater level increased by 1.0-2.0 m during the study period. It also showed a slight improvement in the groundwater quality parameters, mainly a decrease in TDS, Cl - and NO 3 levels by 5.5, 17.1 and 20%, respectively, resulting from the relatively better quality of the recharged wastewater. Nevertheless, the level of boron and ammonium in the groundwater wells showed a significant increase over time by 96 and 100%, respectively. Moreover, the infiltration rate was slowed down in time due to the relatively high level of total suspended solid (TSS) in the infiltrated wastewater.- levels by 5.5, 17.1 and 20%, respectively, resulting from the relatively better quality of the recharged wastewater. Nevertheless, the level of boron and ammonium in the groundwater wells showed a significant increase over time by 96 and 100%, respectively. Moreover, the infiltration rate was slowed down in time due to the relatively high level of total suspended solid (TSS) in the infiltrated wastewater.

Municipal wastewater treatment plant (WWTP) effluents represent an important contamination source of antibiotic resistance, threatening the ecological safety of receiving environments. In this study, the release of antibiotic resistance to sulfonamides and tetracyclines in the effluents of ten WWTPs in China was investigated. Results indicate that the concentrations of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) ranged from 1.1 × 10 1 to 8.9 × 10 3  CFU mL -1 and 3.6 × 10 1 (tetW) to 5.4 × 10 6 (tetX) copies mL -1 , respectively. There were insignificant correlations of the concentrations of ARB and ARGs with those of corresponding antibiotics. Strong correlations were observed between the total concentrations of tetracycline resistance genes and sulfonamide resistance genes, and both of which were significantly correlated with intI1 concentrations. Statistical analysis of the effluent ARG concentrations in different WWTPs revealed an important role of disinfection in eliminating antibiotic resistance. The release rates of ARB and ARGs through the effluents of ten WWTPs ranged from 5.9 × 10 12 to 4.8 × 10 15  CFU d -1 and 6.4 × 10 12 (tetW) to 1.7 × 10 18 (sul1) copies d -1 , respectively. This study helps the effective assessment and scientific management of ecological risks induced by antibiotic resistance discharged from WWTPs., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Antibiotic resistance genes (ARGs), as emerging environmental contaminants, have become a threat to human health. Recent studies have demonstrated that the effluent from wastewater treatment plants is a significant point source of ARGs released into the environment. In this study, we investigated the effectiveness of coagulation technology in the removal of ARGs from treated wastewater. Specifically, we measured the removal of five ARGs (two sulfonamide resistance genes, sulI and sulII, and three tetracycline resistance genes, tetO, tetW and tetQ) and the class 1 integron intI1 gene via the application of two coagulants: FeCl 3 and polyferric chloride (PFC). Moreover, the removal of dissolved organic carbon (DOC), NH 3 N and total phosphorus (TP) in the coagulation process was investigated. The coagulation process effectively removed ARGs from the effluent with 0.5-log to 3.1-log reductions. Significant removal correlations were observed between dissolved NH 3 N and DOC, intI1 and sulI, sulII and tetO, sulII and tetW, and tetO and tetW, implying that the co-removal of DOC, dissolved NH 3 N, the intI1 gene and different ARGs played an important role in ARG loss during coagulation with Fe-based coagulants. These results indicate that coagulation may play a promising role in ARG reduction in wastewater treatment plants., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Residual ammonia and pathogenic microorganisms restrict the reclamation and reuse of wastewater treatment plant (WWTP) effluent. An electrochemical system was developed for the simultaneous removal of ammonia and disinfection of actual WWTP effluent. The performance of the electrochemical process on synthetic wastewater at different chloride ion concentrations was also investigated. Results demonstrated that the optimal chloride concentration for ammonia and Escherichia coli (E. coli) removal was 250 mg/L. Successful disinfection of E. coli in actual effluent was achieved at 0.072 Ah/L, but the inverse S-type inactivation curve indicated that there was a competitive consumption of strong oxidants and chloramines working as another disinfectant. A higher electric charge (0.58 Ah/L) was required to simultaneously reduce E. coli and ammonia to levels that meet the reclamation requirements for WWTP effluent. At this electric charge, no trihalomethane, chlorate, or perchlorate in the system was observed, indicating the biological safety of this process. These results demonstrate the potential of this electrochemical process as a tertiary wastewater treatment process for WWTP effluent reclamation purposes.

OTNE [1-(1,2,3,4,5,6,7,8-octahydro-2,3,8,8-tetramethyl-2-naphthyl)ethan-1-one; trade name Iso E Super] is a fragrance ingredient commonly used in consumer products which are disposed down the drain. This research measured effluent and sludge concentrations of OTNE at 44 US wastewater treatment plants (WWTP). The mean effluent and sludge concentrations were 0.69 ± 0.65 μg/L and 20.6 ± 33.8 mg/kg dw respectively. Distribution of OTNE effluent concentrations and dilution factors were used to predict surface water and sediment concentrations and distributions of OTNE sludge concentrations and loading rates were used to predict terrestrial concentrations. The 90th percentile concentration of OTNE in US WWTP mixing zones was predicted to be 0.04 and 0.85 μg/L under mean and 7Q10 low flow (lowest river flow occurring over a 7 day period every 10 years) conditions respectively. The 90th percentile sediment concentrations under mean and 7Q10 low flow conditions were predicted to be 0.081 and 1.6 mg/kg dw respectively. Based on current US sludge application practices, the 90th percentile OTNE terrestrial concentration was 1.38 mg/kg dw. The probability of OTNE concentrations being below the predicted no effect concentration (PNEC) for the aquatic and sediment compartments was greater than 99%. For the terrestrial compartment, the probability of OTNE concentrations being lower than the PNEC was 97% for current US sludge application practices. Based on the results of this study, OTNE concentrations in US WWTP effluent and sludge do not pose an ecological risk to aquatic, sediment and terrestrial organisms., (Copyright © 2016 Elsevier Ltd. All rights reserved.)