Search

Objective . A previously reported experiment indicated that Arabidopsis thaliana seeds with cryptochrome mutation His-CRY2 showed more robust photomorphogenic growth when hydrated with intentionally treated water as compared to untreated water. The present study attempted to replicate that outcome, adding a condition where the seeds were also intentionally treated. Arabidopsis seeds were used because they contain a photosensitive flavoprotein called cryptochrome (CRY). CRY has been proposed as a possible “transducer” of intention in living systems because it is thought to have quantum biological properties, and as such, it might potentially be sensitive to quantum observer effects. Design Three Buddhist monks directed their attention toward commercially bottled water and Arabidopsis seeds while holding the intention to improve the growth of the plant. As a control condition, no attention was directed at water or seeds from the same sources. Under double-blinded conditions, treated and untreated seeds were placed in an incubator, hydrated with treated or untreated water, and exposed to either continuous blue light or blue plus far-red light. The seed germination process was repeated three times, each time using new seeds. A 2 × 2 × 2 ANOVA, with water, seeds, and light as factors, was used to analyze the results. Results . Treated water was associated with enhanced photomorphogenic growth, as reflected by a shorter hypocotyl length (p = 0.04) and greater amounts of chlorophyll (p = 0.0005) and anthocyanin (p = 2 × 10−6). Treated seeds resulted in greater amounts of chlorophyll (p = 0.04), but also a longer hypocotyl (p = 0.0004) and less anthocyanin (p = 0.01). Plants exposed to blue plus far-red light were constantly more robust than plants grown under blue light, regardless of the type of water or seed (p Conclusion . Intentionally treated water improved the growth of the His-CRY2 variant of Arabidopsis, confirming results of an earlier experiment. Enhanced growth associated with exposure to blue plus far-red light also confirmed to known effects. A more complex relationship was observed with treated seeds. Further research is required to understand the latter outcome, as it may provide clues about the underlying mechanisms of intentional influences.

Fresh-water comes from the rain which finally goes into the ocean via rivers. The human beings store this water and use it in a variety of purposes such as drinking, washing, irrigation and in industries etc., Wastewater is generated after the utilization of pure water in domestic, industrial, agricultural, municipal and other activities. The growing population and urbanization are the principal reason of continuous increase in wastewater generation. Wastewater contains a number of contaminants like organic materials, biological components and toxic inorganic compounds which cause adverse effect on the human health. Many inorganic chemicals are conventionally used as coagulant for the treatment of wastewater. Theses coagulants have the ability to change the physico-chemical properties of the treated water. In this review paper, we have described the used of naturally-occurring polymers as coagulants in wastewater treatment. These coagulants have more potential for coagulation and are also eco-friendly and biodegradable in nature; moreover, these coagulants do not adversely affect the human health and do not induce change in the physico-chemical properties of treated water.

Introduction Acute viral gastroenteritis is a major public health concern, especially among children younger than 5 years of age. The aim of this study was to determine the occurrence of human astrovirus infection in children with acute gastroenteritis. Methods Stool specimens were collected from 506 children under 5 years of age hospitalized with acute diarrhoea (289 male and 208 female), and human astrovirus was investigated by RT-PCR. Associations of socio-demographic, clinical, and behavioural conditions with infection were analysed. Results The overall prevalence of human astrovirus was found to be 10.3%. The mean age of positive cases was 12.41 ± 6.21 months and this was associated with infection (p = 0.013). Children >18 months of age were at three times the risk of infection when compared to those aged 0–6 months (odds ratio (OR) 3.19, 95% confidence interval (CI) 1.15–8.88; p = 0.026). Children living in houses with more than one room (OR 0.60, 95% CI 0.28–0.96; p = 0.036) and mothers using treated water (OR 0.47, 95% CI 0.25–0.86; p = 0.015) were associated with reduced infection. Conclusions In this study, infection with astrovirus was common in acute gastroenteritis cases among children younger than 5 years of age. Drinking treated water and living in non-crowded environments protected the children from infection.

For centuries noses, eyes, and mouths have assessed the safety of drinking water. Yet by the end of the long nineteenth century, the nascent professional water worker corps in the United States and Europe began to distance themselves from everyday sensory approaches to judging a water’s potability. Historians and geographers have explored the rise of urban water infrastructures as well as shifting approaches to water analysis. However, the changing role of sensory analysis in erasing waters’ biogeophysical histories, as well as the political ramifications of creating authoritative modes of sensory labor that exclude aesthetic evaluations of quality, remains relatively unexamined. This paper asks how water workers’ efforts to standardize and make objective the embodied labor of managing municipal water shifted not only how sensory knowledge is made, but also who has access to sensory knowledge about place. Drawing on technical documents, scientific papers, and production manuals, I examine the emergence of a new standardized system for characterizing and mitigating off odors and flavors found in raw and treated water during the first half of the twentieth century in the United States. This analytical assemblage was built on the precepts of nineteenth-century Fechnerian psychophysics. Grounded in the idea that small increases in stimulation are proportionally accompanied by small increases in sensation, psychophysics offered a way to express and test the relationship between stimulus and experience by identifying the point at which a difference in stimuli was ‘just noticeable’. Through attending to the role of tasting, smelling bodies as sites of scientific knowledge production, and as sites where scientific knowledge is called into question, I show that water workers used estimation of the ineffable to break away from or transcend locale. In the process, they made the water treatment laboratory into a space thoroughly embedded in place, even as they in turn set in motion efforts to remove place from the water sent to consumers throughout the provisioning system.

Small scale ultrafiltration (UF) systems have been increasingly used in rural areas for drinking water supply, but their effectiveness in guarantying microbiological water safety at household level has rarely been assessed. Therefore, this study surveyed six representative villages where UF was utilized for full-scale drinking water supply for at least four years. At each village, the influent and the effluent from every stages of the treatment, as well as household tap water, were sampled and analyzed for microbiological indicating parameters, including total coliform count, Escherichia coli count, and heterotrophic plate count. The results were further assessed against current drinking water quality guidelines and standards. It was found that: (1) the qualification rate of household tap water samples varied substantially in the studied villages (0-75%), mainly due to the lack of post-disinfection and the occurrence of fecal contamination during water distribution; (2) UF appeared to be effective in controlling microbial contamination for small-scale systems with high-quality source water, while for systems using inferior source water, fecal contamination during water distribution necessitated continuous post-disinfection; and, (3) existing monitoring of membrane operational parameters cannot ensure microbial quality of treated water, and therefore, routine monitoring of microbial indicators in household water is recommended.

Plasma treated water (PTW), produced by atmospheric-pressure plasma treatment of water, usually contains various reactive oxygen and nitrogen species (RONS). This study aimed at evaluating the effectiveness of different types of PTW on seed germination, seedling growth and microbial sterilization during the germinated mung bean processing. Results showed that air-PTW possessed outstanding abilities in improving seed germination and seedling growth with a germination index of 95.50% and a vigor index of 1146.64, and in microbial decontamination. The physicochemical properties of the PTW were analyzed to better understand the PTW stressed germination. Some physiological parameters like the activity of superoxide dismutase (SOD), the contents of malondialdehyde (MDA) and phytohormone (indole acetic acid (IAA) and abscisic acid (ABA)) during germination were also evaluated. This study suggested that air-PTW treatment could indeed provide a green and effective mean of stimulating seed germination and plant growth, and thus accelerate the growth cycle. Industrial relevance Increasing the production of food by using both economical and environmentally friendly means has been deemed as an urgent matter to sustain the food demand of rapidly growing world population. The results of this study suggest that PTW presents a great opportunity to address this need by increasing seedling growth and viability. PTW treatment is an environment-friendly and low-cost mean of stimulating seed germination and plant growth, which possesses the potential of scale up or industrial applications in relevant fields.

Calibrated adsorption-based passive samplers were used for time-integrative monitoring of microcystins (MCs) in three full-scale drinking water treatment plants (DWTPs) in the Czech Republic during two vegetation seasons (Jun-Nov), in parallel with traditional discrete sampling. MCs were detected in epilimnetic water samples at concentrations up to 14 mu g/L, but their levels in raw water in DWTPs were below 1 mu g/L WHO guideline value for drinking water. Conventional treatment technologies (coagulation/filtration) eliminated cyanobacteria and intracellular toxins but had a limited removal efficiency for extracellular toxins. MCs were regularly detected in final treated water, especially in DWTPs equipped only with the conventional treatment, but their concentrations were below the quantitation limit of discrete sampling (

The aim of this work was to study concurrent removal of nitrate, arsenic and iron in an attached growth reactor (AGR) based on bio-sulphidogenesis treating simulated and real-life ground water. A lab-scale bioreactor system was monitored for a period of 511 days under conditions identical to those prevailing at full-scale to assess the relative influence of empty bed contact time (EBCT) (20–90 min), backwash strategies (water-nitrogen and water-air), temperature (20–50 °C), pH (6.6–8.4) and shut down on reactor performance and recovery. Complete removal of nitrate (50 mg/L) and over 95% removal of iron (3 mg/L) occurred. Arsenic removal efficiency was around 99% (500 μg/L) and treated water arsenic concentration was in compliance with the World Health Organization and Indian Standard of 10 μg/L. Port sampling along the depth of bioreactor shows shifting of terminal electron accepting process zones at lower EBCT of 20 min and after air assisted backwashing. The temperature range of 20–50 °C and pH range of 6.6–8.4 were applicable for arsenic removal in natural conditions. Precipitated biosolids were analysed using electron microscopy. Biogenic sulphides resulted in the precipitation of arsenosulphides and iron sulphides, which concurrently removed arsenic and iron. This study suggests that a sulphidogenic bioreactor may help to set the basis for concurrent removal of nitrate, arsenic and iron from real-life groundwater using mixed biofilm bacterial community.

Effluents from wastewater treatment plants (WWTPs) are widely recognized as the main source of emerging contaminants (including stimulants and antibiotics) in natural water courses. The problem is aggravated in those regions where water is scarce and its reuse is necessary. With the aim of avoiding these problems, the present paper reports the results obtained by installing a nanofiltration membrane at the outlet of the secondary decanter at the WWTP situated in the municipality of Medina Sidonia (SW Spain). Permeate samples were taken over a period of 72 h while the membranes were operating. Contaminants belonging to the aforementioned families (caffeine, theobromine, theophylline, amoxicillin and penicillin G) were analysed by means of liquid chromatography with mass spectrometry (UPLC-MS). The results indicate that nanofiltration removed these contaminants from the wastewater turning the treated water as suitable to be reused for all the uses included in the Spanish Royal Decree 1620/2007 on water regeneration and reuse.

Contaminants of emerging concern (CECs), including per- and polyfluoroalkyl substances (PFAS), are of interest to regulators, water treatment utilities, the general public and scientists. This study measured 17 PFAS in source and treated water from 25 drinking water treatment plants (DWTPs) as part of a broader study of CECs in drinking water across the United States. PFAS were quantitatively detected in all 50 samples, with summed concentrations of the 17 PFAS ranging from, GRAPHICAL ABSTRACT

The study investigates the content of microplastic particles in freshwater and drinking water. Specifically, three water treatment plants (WTPs) supplied by different kinds of water bodies were selected and their raw and treated water was analysed for microplastics (MPs). Microplastics were found in all water samples and their average abundance ranged from 1473 ± 34 to 3605 ± 497 particles L−1 in raw water and from 338 ± 76 to 628 ± 28 particles L−1 in treated water, depending on the WTP. This study is one of very few that determine microplastics down to the size of 1 μm, while MPs smaller than 10 μm were the most plentiful in both raw and treated water samples, accounting for up to 95%. Further, MPs were divided into three categories according to their shape. Fragments clearly prevailed at two of the WTPs and fibres together with fragments predominated at one case. Despite 12 different materials forming the microplastics being identified, the majority of the MPs (>70%) comprised of PET (polyethylene terephthalate), PP (polypropylene) and PE (polyethylene). This study contributes to fill the knowledge gap in the field of emerging microplastic pollution of drinking water and water sources, which is of concern due to the potential exposure of microplastics to humans.

Earlier, we reported on soluble microbial products-mediated chloramine decay in nitrifying waters. However, we neither separated the agent(s) nor identified the factors that enhanced the production of chloramine-decaying soluble microbial products (cSMPs). Experiments were conducted by feeding reactor sets (each consisting of five reactors connected in series) with treated water (3–8 mg-DOC.L−1) obtained from a water treatment plant. The reactors simulated various nitrifying conditions that are experienced in a chloraminated system. In unfiltered samples obtained from nitrified reactors, about 89–93% of the dosed chloramine decayed within 40 h. The cSMP-mediated decay accounted for 21–39% of all chloramine decay in the samples from 0 to 5 mg-C.L−1 fed reactors and 15% in the samples from 7 to 8 mg-C.L−1 fed reactors. Microbial processes (mediated by nitrifiers and/or heterotrophs) and biomass-associated microbial products (BMPs) in insoluble form accounted for 13–21% for the reactors fed with 0–5 mg-C.L−1 and 34% for those fed with 7–8 mg-C.L−1. The cSMPs were separable with a 30 kDa cut-off membrane but not with 50 or 100 kDa membranes, i.e., they were above 30 kDa but below 50 kDa in size, and were confirmed to be a protein(s). The protein(s) accelerated chloramine decay by accelerating chloramine auto-decomposition and nitrite oxidation. As opposed to the traditional belief, unknown factors accounted for approximately 34–53% in commonly encountered re-chloraminated nitrifying waters (2–5 mg-DOC.L−1). Understanding the identity and role of these factors – such as cSMPs, BMPs, heterotrophs - will lead to a better control of chloramine.

The projected radiation dose to the public due to the release into the environment of the Fukushima treated water was assessed using the methodology of the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The assessment was carried out for ten key radionuclides (3H, 60Co, 125Sb, 90Sr, 106Ru, 129I, 134Cs, 137Cs, 14C, and 99Tc) in the treated water, and the mean measured radioactivity concentration of each radionuclide was used as the source term. The release scenario assumed was that all of the radionuclides in the tanks were released continuously into the marine or atmosphere for one year without additional purification. In the case of the marine release, the estimated public exposure dose in Japan and in the Republic of Korea was 0.85 μSv/y and 1.4E-5 μSv/y, respectively. In the case of atmospheric release, the estimated public dose at 5 km from the release point (FDNPS) and in Busan, the Republic of Korea (about 1,090 km from FDNPS) was 40.6 μSv/y and 0.061 μSv/y, respectively. The exposure dose level arising from both release options is unlikely to have a harmful radiological effect on the public because it is much lower than the annual dose limit for the public (1,000 μSv/y).

The addition of water treatment chemicals has always been considered as a standard operation in water and wastewater treatment. The concentration of chemicals was usually kept to the minimum necessary to achieve a good quality of potable or otherwise treated water. A significant interruption to the status-quo occurred more than 20 years ago after a severe and highly publicized outbreak of Cryptosporidium parvum oocysts. The strategic planning after the outbreak was to shift from physical-chemical to physical treatment methods, such as membrane filtration and UV disinfection. As such, the new procedures were supposed to eliminate the threat of water contamination through a minor addition of chemicals. Such was the mistrust and disappointment with water treatment chemicals themselves. Indeed, water treatment technologies are now using novel physical treatment methods. Membranes largely replaced granular filtration, and UV is paving the way towards minimization or elimination of the use of classic disinfection chemicals, such as chlorine and its derivatives. Yet, far from the “high-tech” revolution in water treatment technologies actually reducing the use of chemicals, the latter has in fact been significantly increased. The “conventional” chemicals used for pre-treatment, disinfection, corrosion prevention, softening and algae bloom depression are all still in place. Furthermore, new groups of chemicals such as biocides, chelating agents and fouling cleaners are currently used to supplement them. These latter are the chemicals needed to protect the high-tech equipment, to optimize the treatment, and to clean the equipment between uses. The health effects of the new chemicals introduced into water are yet to be fully established. Typically, a higher treatment efficiency requires effective chemicals, yet these are not always environmentally friendly. It seems obvious that the “high-tech” revolution currently affects the sustainability of water resources, and certainly not in a completely positive way. In short, the adverse effects of the introduction of such a significant amount of treatment chemicals into our sources of water are yet to be evaluated.

Many parts of the world have excess fluoride in drinking water. At some locations, nitrate is also in excess. Hence, reverse osmosis (RO) units have been installed at several villages in India. Reverse osmosis is a good technique, but it has the disadvantage of discarding a considerable amount of the inlet water as a reject stream. This is an unsustainable way of using water. Two adsorbents, namely, a hybrid anion exchange resin embedded with zirconium oxide nanoparticles (HAIX-Zr), and activated alumina (AA) were used in column experiments. For water containing only F − , HAIX-Zr had a better capacity than AA. The same trend was observed with synthetic water samples containing other ions in addition to F - . However, for RO reject, the converse was true, and the capacities of AA and HAIX-Zr decreased significantly. For AA, the presence of a small concentration of HCO 3 − increased the uptake of F - by 100% compared to water containing only F - . For HAIX-Zr, the adsorption capacity decreased as the concentration of co-ions increased. The cost of treated water varied from 0.1–1.5/L (US $ 0.002–0.03/L) for AA and 0.2–11.5/L (US $ 0.004–0.23/L) for HAIX-Zr.

Disinfectants have been widely assessed against conidia, zoospores and mycelial growth of fungal plant pathogens in water, however, studies against sclerotia or melanized structures are limited. The disinfectants OX-VIRIN®, OX-AGUA AL25® and Deccoklor® reduce Verticillium dahliae conidia in water, but their potential efficacy in reducing sclerotia of the pathogen in water remains unknown. In this study, sclerotia of six V. dahliae isolates differing in virulence were exposed in vitro to a range of concentrations of the mentioned disinfectants for 30 days to evaluate the suppressive efficacy. In addition, concentrations with higher suppressive effect were tested for their preventive efficacy by means of assays where treated water was subsequently infested. Concentration and monitoring time (1 min, and 5, 15 and 30 days post-chemical treatment; dpc) were the critical factors for the efficacy of the chemicals, whereas variations depending on isolates virulence were negligible. The three highest concentrations of OX-VIRIN® (3.2–51.2 mL L−1) and the two highest concentrations of OX-AGUA AL25® (0.4175 and 1.2525 mL L−1) showed an average suppressive efficacy ranging from 87.8 to 100% and 99.2–100% at the last three sampling times, respectively. Deccoklor® was ineffective at the evaluated concentrations. The three highest concentrations of OX-VIRIN® and the highest concentration of OX-AGUA AL25® maintained a preventive efficacy above 97 and 95%, respectively, at all sampling times. For OX-AGUA AL25® at 0.4175 mL L−1, the preventive efficacy fluctuated over sampling time, but it was of at least 68.9% at 30 dpc in repeated experiments.

Unpleasant taste or smell are more importantly constituents of drinking-water, lead to complaints from consumers. Dye and organic matter as well change in disinfection practice may generate taste and an odorous compound in treated water. According to low efficiency of conventional methods to remove taste and odor compounds, present study was aimed to evaluate the performance of air stripping tower- Poly Aluminum Chloride (PAC) integrated system to remove odor and taste, dye and organic materials from drinking water. Different air to water ratio and PAC doses were used to remove considered parameters in certain condition. The results of this study indicated that the maximum removal efficiency of 86.2, 76.47, 58.46 and 41.27% of taste and odor, dye, COD and TOC were achieved by the air stripping tower- PAC integrated system, respectively. However, the physico-chemical characteristics of water and adsorbent effect on the of substances removal efficiency considerably. It can be stated that the air striping tower - PAC integrated system is able to reduce the odor and taste-causing substances and organic matter to a level which is recommended by the Institute of Standards and Industrial Research of Iran. Keywords: Air stripping tower, PAC, Odor and Taste, Dye, Organic materials, Drinking water, Saqqez city

In this study, the effects of accelerated carbonation and hydraulic retention time (HRT) on the lead (Pb) removal in pervious concrete filter (PCF) were investigated. The Pb containing solution of 8 mg/L concentration was constantly passed for 60 min through three PCF monoliths that were arranged in series with progressively decreasing water heads. This three-tier filtration experiment was conducted on PCFs, which were tested right after initial curing as well as after an accelerated carbonation exposure. Cumulatively, the Pb removal in 7-day cured and carbonated PCFs were found to be 97.2% and 99.1%, and thus it showed that the CO2 uptake by PCF marginally improved the Pb fixation, and further these results strongly recommend the HRT consideration in concrete filter design for real-field applications. Moreover, the leachability test results suggests that the change in physical characteristics of treated water from carbonated PCF was found lesser than 7-day cured PCF regardless of the inlet solution pH. The Ca ions removed from both PCFs post-treatment were found well below drinking water acceptable limits. The cost of both PCFs were estimated, which appeared inexpensive unlike treatment units that are currently in practice. On the whole, this study effectively demonstrated the potential of 7-day cured and carbonated PCFs for cost-effective Pb removal.

Solar disinfection (SODIS) of urban wastewater can be a suitable technology for improving the microbiological quality of reclaimed water as a complement to other extensive and environmentally friendly technologies such as microalgae biotreatment. The objective of this work is to evaluate the feasibility of incorporating the SODIS technology at the end of a pilot scale urban wastewater treatment plant (WWTP) where the processes are based on microalgae biotechnology and comprising three Upflow Anaerobic Sludge Blanket (UASB, 20 m3 each one) reactor, six High Rate Algal Ponds (HRAP, 32 m2 each one), and a Dissolved Air Flotation (DAF, 1 m3) unit. E. coli concentration was monitored at the effluent of the different units (UASB, HRAP, DAF) of the pilot WWTP. The efficiency of the SODIS process was studied for the inactivation of three of the commonly employed indicator microorganisms (Escherichia coli, Enterococcus spp. and Clostridium perfringens) using a compound parabolic collector (CPC) for five months under various conditions of irradiance and temperature. E. coli and Enterococcus spp. were more effectively disinfected by the SODIS unit (2.9 and 2.5 logarithms of reduction on average, respectively) than by the HRAP (2 and 1.1) or the DAF (0.9 and 0.1). On the contrary, the DAF technology achieved better reduction rates of C. perfringens (1.7) than the SODIS (0.9) and the HRAP (0.1). No regrowth of any microorganisms was detected during dark storage after the SODIS treatment. Incorporating a SODIS unit after the non-conventional WWTP processes substantially increases the possibilities for reuse of the treated water after receiving a cumulative UV radiation dose of 25 W·h/m2 (50 min of normalized time of solar illumination). The surface requirement of the SODIS equipment would be 3.5 times smaller than the HRAP's surface.

The pollution of coastal regions worldwide has been of a great concern due to the presence of endocrine disrupting chemicals (EDCs). These chemicals find their way to the marine environment via the sewage treatment plants (STPs). Hence, this study was designed to investigate the status and sources of EDCs and their effect on fish in Kuwait's coastal areas, from the chemical and biological perspectives. The assessment of three STPs indicated the presence of significant levels of phthalates (19 and 31µg/l), alkylphenols (85 and 159ng/l), and estrogens (30 and 368ng/l) in both inflow and outflow samples. The analysis of samples from field exposure sites revealed significant levels of EDCs in seawater (phthalates: 2.1-4.6µg/l; alkylphenols: 1.2-16.4ng/l; estrogens: 0-36.2ng/l) and sediment (phthalates: 2.1-15.7mg/kg dry wt; alkyphenols: 2.5-15.1µg/kg dry wt.; estrogens: 4.1-214.2µg/kg dry wt.) samples. The biological perspective investigated through the exposure of fish to sewage outlets at five sites. The hepatosomatic index (HSI) revealed a higher level in winter samples 0.48-0.79%) in comparison to summer samples 1-1.5%). Histological observation of hepatic tissue of fish exposed during winter months in all sites, showed much less necrotic changes and hepatic vacuolation in the hepatic tissue of summer exposed fish. Imunnohistochemistry evidences revealed a significant level of positive signals and Vtg localization in the hepatic tissue as the results support the histopathological alterations observed. Results of enzyme-linked immunosorbent assay (ELISA) showed no significant difference between the plasma protein content of winter and summer samples. Overall, the study suggest that there is possible local source or a chronic input of untreated and/or partially treated water due to the significant levels of phthalates, alkyphenols, and estrogens detected in the Kuwait Bay. These levels were enough to initiate alteration in the hepatic tissue of fish exposed to the sewage outlets in Kuwait for two weeks.

A main reverse osmosis (RO) limitation is the operational costs (including energy filtration costs), which are significantly affected by energy costs and the expense of membrane maintenance. Both costs are affected by influent characteristics, including feedwater temperatures (T), electrical conductivity (EC), and recovery set points. A fuzzy logic advanced control system optimizes the RO operational costs considering feedwater EC and T as input values, and the RO recovery setpoint as a control action. Verification results show that, once calibrated, the simulation of the control system can save more than one million euros per year in large RO facilities (>30.000m3·day-1). Which represents a reduction of 0.11€·m-3 of influent treated water The authors would like to acknowledge the support from the RegiReu project (COMRDI16-1-0062) from the Agency for Business Competitiveness (ACCIÓ). Albert Galizia would also like to thank the AGAUR for his predoctoral grant (2021 FI_B 00069). Hèctor Monclús gratefully acknowledges the Ramon y Cajal Research Fellowship (RYC2019-026434-I). LEQUIA and ICRA have been recognized as consolidated research groups by the Catalan Government; codes 2017-SGR-1552 and 2017-SGR-1318, respectively. Gaetan Blandin has received funding from the People Programme (Marie Curie Actions) of the Seventh Framework Programme of the European Union (FP7/2007-2013) under the REA grant agreement n°600388 (TECNIOspring programme), and from the Catalan Government's Agency for Business Competitiveness (ACCIO) Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevier

The disinfection of water for human consumption with chlorine or other compounds produces secondary reactions with the organic matter, generating undesirable disinfection by-products (DBPs). Among these are trihalomethanes (THMs), identified as carcinogenic compounds. This work determined the trihalomethanes concentration, both speciated and total, in treated water distributed and stored in tanks of residential condominiums of different social classes. THMs were quantified using static manual Headspace as preconcentration technique, injecting the vapor phase collected in a GC/FID. The results show that the water distributed to the homes already contains THMs, trichloromethane being the major compound. The Principal Components Analysis (PCA) and Hierarchical Cluster Analysis (HCA) with 60 water samples showed that there is no significant distinction among samples of treated water distributed water and water stored in tanks. This study warns to the importance of controlling the formation of trihalomethanes in water throughout treatment and distribution for users.

A preliminary study was conducted to delineate the ameliorating effect of dietary zinc nanoparticles (Zn-NPs) against thermal stress in Pangasius hypophthalmus reared under concurrent exposure to lead (Pb) and elevated temperature (34 °C). Three diets were formulated such as control (no Zn-NPs), Zn-NPs 10 and 20 mg/kg diet. Two hundred and thirty four fish were randomly distributed in to six treatments groups in triplicates; such as control group (no Zn-NPs in diet and unexposed to Pb and temperature, Ctr/Ctr), control diet with concurrent exposure to Pb and temperature (Pb-T/Ctr), Zn-NPs 10 and 20 mg/kg without stressors (Zn-NPs 10 mg/kg, Zn-NPs 20 mg/kg), Zn-NPs 10 and 20 mg/kg diet with concurrent exposure to Pb and temperature (Pb-T/Zn-NPs 10 mg/kg, Pb-T/Zn-NPs 20 mg/kg). The Pb in treated water was maintained at the level of 1/21th of LC50 (4 ppm) at 34 °C temperature in stressors groups. Post 60 days feeding trial, critical thermal minimum (CTmin), lethal thermal minimum (LTmin), and critical thermal maximum (CTmax), lethal thermal maximum (LTmax) and biochemical attributes on P. hypophthalmus were evaluated. The results indicated that, dietary supplementation of Zn-NPs increased the CTmin, LTmin and CTmax, LTmax in P. hypophthalmus. Positive correlations were observed between CTmin LTmin (Y = − 0.495 + 10.08x, R2, 0.896) and CTmax LTmax (Y = − 0.872 + 4.43x, R2, 0.940). At the end of the thermal tolerance study, oxidative stress and lipid peroxidation (LPO) were significantly reduced and neurotransmitter enzyme was significantly increased in the groups fed with Zn-NPs @ 10 mg and 20 mg/kg diet. Overall results indicated that dietary Zn-NPs can confer protection against thermal stress in P. hypophthalmus.

Chlorination is the oldest and most common method to control water quality and biofouling worldwide. Therefore, ensuring the accuracy of the measurements of residual chlorine concentration in treated water is of significant importance. Various residual chlorine measurement methods are used for industrial and municipal (conventional) or academic research (unconventional) purposes. Previous studies have reported that the conventional methods suffer from diverse interferences that lead to erroneous measurements. However, no recent study has summarized and synthesized the existing interferences related to the measurement methods. In this review, the conventional electrochemical and colorimetric-photometric methods are discussed, along with the unconventional methods, with regard to their principles, advantages, limitations, and recent case studies. Further, conventional method interferences are defined and discussed. In particular, possible solutions for interferences in the widespread colorimetric-photometric method are extensively evaluated, and constructive suggestions are offered toward reducing or avoiding the effects of these interferences.

Fresh water, despite being a renewable natural resource, is currently limited and scarce. Its necessity for life and economic growth has led to permanent conflicts of interest. Social and sectoral dynamics regarding water entail conflicts over use, alterations of natural conditions, effects on its availability, quantity and quality. Due to anthropic activities present in watersheds, freshwater systems around the world face the emergence of innumerable chemical substances that hinder their treatment possesses and favor the formation of other compounds. These include disinfection byproducts (DBPs), which are compounds that represent a risk to human health due to its mutagenic and carcinogenic nature. This study conducts a systematic review of the literature concerning DBPs in drinking water supply systems (DWSS). From the research questions formulated in the review, a knowledge gap has been identified, which suggests the problems linked to the appearance of DBPs in treated water, should be addressed within an interdisciplinary and systemic approach. This implies the development of methodological, sociological, ecological and technological processes that allow an understanding of the problem from a holistic and integrative perspective. The occurrence of DBPs in drinking water treatment plants cannot be reduced to the product of chemical reactions between precursors and disinfectant agents such as chlorine; on the contrary, the problem presumes a much more complex origin that requires an analysis of the actions and processes that are carried out in territories and potentiate the deleterious processes in terms of water quality.

The fluoride removal capability of a new industrial-based chemical coagulant (Formula A) in one- and two-stage coagulation treatments was investigated in present study. Three main controlling factors, the coagulant concentration, reaction time and the initial pH of Formula A were studied on the fluoride removal accordingly, with the aid of other coagulants: Ecogent F-Loc, potassium ferrate (K2FeO4), and sodium aluminate (NaAlO2). Response surface methodology (RSM) was adopted to analyse the controlling factors on the fluoride removal efficiency (R%) using Box-Behnken designs (BBD). The coagulant concentration of Formula A shows the most significant effect on R% and better fluoride removal capability at an initial pH 12. Nevertheless, the R% has been shown to be independent of reaction time. Response optimisation revealed the highest R% (70.12%) can be achieved at 1000 ppm, 10 min of reaction time and initial pH of 2. Furthermore, K2FeO4 has a better R% in low pH regions of 2 to 4. Additionally, K2FeO4 achieved the highest R% (84%) at 1190 ppm and pH 9 with 8.5 min of reaction time. In a single coagulation stage, the use of Formula A or K2FeO4 are not able to meet Environmental Quality (Industrial Effluent) Regulations 2009 with discharge Standard B as specified by Department of Environment Malaysia, while a two-stage coagulation process can meet Standard A. Specifically, the combined formulation of using Ecogent F-Loc(1)- Formula A(2) and NaAlO2(1)- Formula A(2) were able to achieve treated water with less than 2 ppm fluoride. Moreover, recycling treated water also plays a major role in helping industries meet the strict treatment standards.

Herein, a Fe3O4 decorated attapulgite adsorbent (FA) is fabricated for the removal of Cd(II) from wastewater, and subsequently a feasible strategy for converting the saturated waste adsorbent to CdS/FA photocatalyst is reported. Owing to the in situ growth of Fe3O4 on the attapulgite (ATP), the FA adsorbents exhibit enlarged surface area and increased adsorption sites. More importantly, the strong interaction between Fe3O4 and ATP leads to changes of coordination environment around the O‒Fe‒O bond with the ATP. Based on the results of density functional theory calculations, the electrons are more readily transferred from Fe to O, and the hanging O atoms with more electronegativity act as the efficient adsorption sites for Cd(II), efficiently improving the adsorption performance of the Fe3O4 phases. Furthermore, the waste FA adsorbent could be conveniently separated from the treated water by magnets and converted to CdS/FA photocatalyst, which exhibits satisfying degradation efficiency for tetracycline with low concentration. This work provides a potential strategy to optimize the ATP-based materials for heavy ions adsorption and reutilize the waste adsorbents.

This work investigates the separation of emulsified crude oil in saline water (30 g L−1 NaCl) with microbubbles (MBs, D32 = 30–40 µm) and nanobubbles (NBs, D32 = 150–350 nm). Bubbles were generated simultaneously by the depressurization of air-saturated water through a flow constrictor (needle valve). The emulsified oil, after gravity separation of the “free” oil, was flocculated with a cationic polyacrylamide (Dismulgan) at pH 7 and removed by: i. Flotation with MBs and NBs; ii. “Floatation” by NBs; and iii. Flotation with MBs and NBs following floc conditioning by NBs. The best oil removal (>99% efficiency) was obtained at 5 bar and 5 mg L−1 of Dismulgan, reducing the oil content (feed concentration = 334–484 mg L−1) in the treated water to

Arsenic is one of the most dangerous inorganic pollutants present in drinking water, which is released both from certain human activities and naturally from the Earth’s crust. Arsenic is usually present in water in two oxidation states, as arsenite (As(III)) or arsenate (As(V)). Arsenate is usually easier to remove than arsenite. Therefore, the goal of this study is to check the potential use of double filtration for improving As(III) removal and to investigate if something happens with membrane, with arsenic solution, or both, after first filtration of As(III). With this objective, reverse osmosis experiments under specific conditions were conducted to get information about As(III) and As(V) removal efficiencies. Concretely, it was studied the effect of double filtration of arsenic on membrane surface and solution. Moreover, it was investigated the possible competitiveness between arsenic species as well as the occurrence of oxidation and aging effects. Results confirmed that double filtration is an efficient method to treat water that contains arsenite since filtration process might cause permanent changes on the physical structure of this specie, which led to an improvement of As(III) removal efficiency after 2nd filtration (removal efficiencies around 95%). Finally, total arsenic content of the treated water after 2nd filtration fulfilled with the maximum legislated level for drinking water (10 μg L −1 ).

Drinking water monitoring plans are important to characterize both treated and untreated water used for drinking purposes. Access to drinking water increased in recent years as a response to the Millennium Development Goals set for 2015. The new Sustainable Development Goals aim to ensure universal access to safe drinking water by 2030. Within the framework of these global goals, it is crucial to monitor local drinking water systems. In this paper, treated and untreated water from different sources currently consumed in a specific town in Salta, northern Argentina, was thoroughly assessed. Monitoring extended along several seasons and included the physical, chemical and microbiological variables recommended by the Argentine Food Code. On the one hand, treated water mostly complies with these standards, with some non-compliances detected during the rainy season. Untreated water, on the other hand, never meets microbiological standards and is unfit for human consumption. Monitoring seems essential to detect anomalies and help guarantee a constant provision of safe drinking water. New treatment plants are urgently needed to expand the water grid to the entire population.

To provide safe drinking water to urban populations, raw water must be treated in drinking water treatment plants, which are energy-intensive facilities. Previous studies have assessed energy intensity (EI: unit of energy required per unit of treated water) of conventional drinking water treatment plants, but they ignored variations related to water treatment trains. By modeling 179 facilities of four water treatment trains, we explored factors potentially affecting energy intensity, such as removal efficiencies of pollutants and treatment capacities of drinking water treatment plants. We also investigated the economies of scale in energy intensity of drinking water treatment plants. Our results illustrated that the energy intensity of water facilities using pressure filter systems is affected by several pollutant removal efficiencies, but not by plant capacity. In contrast, the volume of water treated is the main factor responsible for the energy intensity in plants using rapid gravity filter systems and, therefore, their energy intensities are significantly affected by economies of scale. The results of this study should be useful to policy makers planning new facilities and developing policies to reduce the carbon footprints of urban water treatment plants.

This work presents results on the removal of Fe 3+ ions as precipitates and nanoparticles of Fe(OH) 3 , at pH 7, by nanobubbles (NBs) and by dissolved air flotation (DAF), a process which combines microbubbles (MBs) and NBs. DAF is a very well-known technology in the treatment of water and wastewater. Studies were conducted at low and high levels of saturation pressures (P sat of 2 and 4 bar) and with “isolated” (single) NBs. The latter were generated at 2.5 bar, after their separation from the MBs. Best results were obtained with flotation at 2 bar, when the concentration of MBs was low and NBs very high. The removal efficiency was 99% of the feed iron content (30 mg L −1 ), and the treated water had a residual total iron concentration of 0.3 mg L −1 and a turbidity of 0.6 NTU (95% reduction). The flotation at 4 bar (mostly by MBs) was faster (0.07 cm s −1 ) due to the high lifting power of the MBs but left a higher residual total iron content of 1.7 of mg L −1 . The flotation with isolated NBs (>10 8 bubbles mL −1 ) attained 91% iron removal due to “floatation” following NBs entrapment and the decrease of the relative density of the aggregates. Flotation of the nanoparticles with NBs was also studied and showed a removal efficiency of about 68%, considered high, for this difficult-to-separate system. All mechanisms involved were discussed in terms of physical, chemical and interfacial phenomena. It is believed that the combination of NBs and MBs has an excellent potential for future separation of particles, including nanoparticles, and will help to broaden applications in removing specific target pollutants from waters and wastewaters.

Mobile and persistent chemicals that are present in urban wastewater, such as pharmaceuticals, may survive on-site or municipal wastewater treatment and post-discharge environmental processes. These pharmaceuticals have the potential to reach surface and groundwaters, essential drinking-water sources. A joint, two-phase U.S. Geological Survey-U.S. Environmental Protection Agency study examined source and treated waters from 25 drinking-water treatment plants from across the United States. Treatment plants that had probable wastewater inputs to their source waters were selected to assess the prevalence of pharmaceuticals in such source waters, and to identify which pharmaceuticals persist through drinking-water treatment. All samples were analyzed for 24 pharmaceuticals in Phase I and for 118 in Phase II. In Phase I, 11 pharmaceuticals were detected in all source-water samples, with a maximum of nine pharmaceuticals detected in any one sample. The median number of pharmaceuticals for all 25 samples was five. Quantifiable pharmaceutical detections were fewer, with a maximum of five pharmaceuticals in any one sample and a median for all samples of two. In Phase II, 47 different pharmaceuticals were detected in all source-water samples, with a maximum of 41 pharmaceuticals detected in any one sample. The median number of pharmaceuticals for all 25 samples was eight. For 37 quantifiable pharmaceuticals in Phase II, median concentrations in source water were below 113ng/L. For both Phase I and Phase II campaigns, substantially fewer pharmaceuticals were detected in treated water samples than in corresponding source-water samples. Seven different pharmaceuticals were detected in all Phase I treated water samples, with a maximum of four detections in any one sample and a median of two pharmaceuticals for all samples. In Phase II a total of 26 different pharmaceuticals were detected in all treated water samples, with a maximum of 20 pharmaceuticals detected in any one sample and a median of 2 pharmaceuticals detected for all 25 samples. Source-water type influences the presence of pharmaceuticals in source and treated water. Treatment processes appear effective in reducing concentrations of most pharmaceuticals. Pharmaceuticals more consistently persisting through treatment include carbamazepine, bupropion, cotinine, metoprolol, and lithium. Pharmaceutical concentrations and compositions from this study provide an important base data set for further sublethal, long-term exposure assessments, and for understanding potential effects of these and other contaminants of emerging concern upon human and ecosystem health.

A national-scale survey of 247 contaminants of emerging concern (CECs), including organic and inorganic chemical compounds, and microbial contaminants, was conducted in source and treated drinking water samples from 25 treatment plants across the United States. Multiple methods were used to determine these CECs, including six analytical methods to measure 174 pharmaceuticals, personal care products, and pesticides. A three-component quality assurance/quality control (QA/QC) program was designed for the subset of 174 CECs which allowed us to assess and compare performances of the methods used. The three components included: 1) a common field QA/QC protocol and sample design, 2) individual investigator-developed method-specific QA/QC protocols, and 3) a suite of 46 method comparison analytes that were determined in two or more analytical methods. Overall method performance for the 174 organic chemical CECs was assessed by comparing spiked recoveries in reagent, source, and treated water over a two-year period. In addition to the 247 CECs reported in the larger drinking water study, another 48 pharmaceutical compounds measured did not consistently meet predetermined quality standards. Methodologies that did not seem suitable for these analytes are overviewed. The need to exclude analytes based on method performance demonstrates the importance of additional QA/QC protocols.

This paper reports on the effects of an oxidation–reduction potential (ORP) control on the electrochemical Fenton-type process (EFT process) and the efficacy of a combined approach, namely, the EFT process with an ORP control together with an activated sludge process, on the treatment of wastewater contaminated with 1,4-dioxane. The EFT process with an ORP control was able to improve the current efficiency from 16.9% to 73.6–81.9%. A superior performance for both the current efficiency and the treated water quality was recorded by the EFT process with an ORP control of 1000 mV. This superior result was ascribed to the approach preventing an excessive accumulation of hypochlorous acid. Two combined processes, namely, an activated sludge process followed by the EFT process with an ORP control (AS-EFT process) and the EFT process with an ORP control followed by an activated sludge process (EFT-AS process), were examined by using 1,4-dioxane contaminated municipal wastewater. As a result, the AS-EFT process was superior to the EFT-AS process in respects of both energy consumption and the performance of chemical oxygen demand (COD) removal, as well as the removal of 1,4-dioxane, due to the smaller COD loading onto the EFT reactor in the AS-EFT process.

Attempts were made in this study to observe the effect of agricultural based natural coagulant (Moringa Oleifera seed) to replace the synthetic coagulants. Natural coagulant reduced 99.5% turbidity of pharmaceutical wastewater. TDS reduces from 1735 to 776 mg/l and TSS 1000 to 450 mg/l. We observed the slight decrement in the value of the BOD and COD from 3776 mg/l to 1100 mg/l and 13728 mg/l to 12425 mg/l respectively during the initial six hours of sedimentation. The next day, the BOD and COD reduce up to the value 5135 mg/l and 373.8 mg/l respectively. The benefit of natural coagulant (Moringa Oleifera) is that it does not reduce pH as a chemical coagulant; hence the treatment to adjust pH of the treated water does not require further.

The use of reclaimed or treated water from urban wastewater treatment plants for irrigation has been proposed as an alternative water source to address water scarcity issues in Europe. In this paper using agro-economic modelling, we analyse if treated water available for agriculture has the potential to reduce freshwater abstraction and, consequently, water stress. Implementing exogenous treated water quantities as an additional water supply at NUTS 2 level in the CAPRI model, we found that treated water reuse is a possible alternative supply source to address water shortages with a very negligible effect on farmers’ income and food production in the EU. However, the actual water reuse and water stress reduction is very limited due to high costs. Even climate change effects on water availability and precipitation failed to induce higher use. The one-size-fits-all approach modelled via a flat rate water price only encourages the reuse of treated water in a limited number of EU member states. Thus, in order to maximise the potential of reused water to address water scarcity, different rates should be used so as to ensure higher treated water volumes at lower costs., Highlights • Water reuse is a possible alternative supply source to address water shortages. • Negligible effect on farmer's income and food production in EU. • Actual water reuse and water stress reduction is very limited. • Financial incentives in form of subsidies necessary to improve water reuse for irrigation.

Wastewater treatment plants (WWTPs) are important sources of microplastics (MPs), having a high daily discharge of MPs despite a relatively high removal efficiency of MPs. Recently, MPs have been detected in drinking water purification facilities (DWPFs), indicating a direct threat to humans. In this review, we summarize published papers on the occurrence and removal efficiency of MPs, focusing on the status of removal mechanisms through different unit operations and processes. For WWTPs, the mass concentrations of MPs in influent ranged from 61 to 5,600 µg/L, and 0.5–170 µg/L of MPs were found in treated effluent, representing an overall removal efficiency of 93.8%–99.8%. Due to limited publications using mass as MP concentration, the comparison of MP abundance among studies was based on the number concentration. MPs have been found in influents at levels of 1.01–31,400 items/L, and in treated effluents at 0.004–447 items/L, with a high variation of MP removal from 10.2% to 99.9%. Preliminary and primary treatments contribute to MP removal, while the efficiency of secondary and tertiary treatments is highly dependent on the applied techniques. Disinfection has a relatively high potential to breakdown MPs into smaller sizes. For DWPFs, MPs in raw water ranged from 1 to 6,614 items/L, and 1–930 items/L of MPs were found in treated water, representing an overall removal efficiency of 66.9%–100% regardless of the treatment types. Yet, the understanding about the role of DWPFs on MP removal is inadequate. Although many studies on WWTPs have been published, many issues have yet to be resolved, and further research is warranted on standardization of analytical methods and the removal mechanisms behinds to develop effective remediation of MPs in WWTPs and DWPFs.

Plastic-contaminated drinking water is currently a global concern. This study focused on the microplastics (MPs) contamination in a conventional water treatment plant (WTP) in Thailand. MPs were enumerated based on size fractions (6.5–≥500 μm) and morphology, and the polymer types of the sorted MPs were detected. Also, the MPs removability in the different treatment units was evaluated. Grab samples were collected in the dry and rainy seasons from five sampling points (9 L from each). These samples were raw water, effluents of the screen, clarifier, and filter, and treated drinking water. Optical microscopy, ATR-FTIR spectroscopy (300–≥500 μm), Nile Red-tagging (6.5−300 μm), and Confocal Raman spectroscopy (1−300 μm) were used as the analytical techniques. The overall removal efficiency of the WTP was found to be 67.6 % and 57.2 % in the dry and rainy seasons, respectively, with an average of 609.1 ± 84.7 p/L still present in the treated water. Clarification and dual media-filtration contributed toward the removal of MPs. The smallest-size fraction (6.5−53 μm) dominated the samples, while fibers and fragments were abundantly found. PE, PP, PET, PA, and PVC were commonly identified. Possible sources of MPs contamination can be from raw water and contamination from within the WTP. A substantial number of MPs escape with treated effluent, imposing a challenge on the drinking water quality in Thailand. The current study found a high abundance of MPs within the 6.5−300 μm range, largely representing fibers. Given the evidence of their cytotoxicity by the latest researches, the contamination within WTPs should be monitored.

Polycyclic aromatic hydrocarbons (PAHs) are mutagenic and bio-accumulates in nature. This research aims to determine the ecological and health risk assessment of PAHs in Sungai Perak, Malaysia. The sampling was conducted at the up and downstream of Sungai Perak in the district of Perak Tengah, Malaysia. The sampling stations were Tanjung Belanja Bridge (TBB), Water Treatment Plant Parit (WTPP), Parit Town Discharge (PTD), Water Treatment Plant Senin (WTPS) and Water Treatment Plant Kepayang (WTPK). The water treatment plants channel water through the distribution network, to Manjung (249,600 people), Perak Tengah (249,600 people), Kinta (810,400 people) and Hilir Perak (144,400 people) districts. The hazard quotient (HQ) and hazard index (HI) were applied for ecological and health risk assessments. The lifetime cancer risk (LCR) was employed for the health risk assessment. The PAHs contamination level presumptions for all sampling campaigns were low (0–100 μg/L). The HI values of ecological and health risk assessments were found to be aligned with each other. The HI values for raw water were below one ( 1) indicating to high risk to aquatic organisms and human health. However, the LCR for raw and treated water exceeded the maximum permissible limit, 1.0 × 10−6 equals to cancer risk of 1 in 1,000,000 people. The LCR for raw water were 1.71 × 10−4 (TBB), 1.35 × 10−4 (WTPP), 1.43 × 10−4 (PTD), 9.54 × 10−5 (WTPS) and 2.37 × 10−4 (WTPK). Meanwhile, the LCR for treated water were 6.90 × 10−5 (WTPP), 5.42 × 10−5 (WTPS) and 2.63 × 10−4 (WTPK). The conventional water treatment system appears to be inefficient to remove PAHs, risking the security of public health. Thus, restructuring the infrastructure of water treatment plants or considering an alternative to rivers as domestic water sources are highly recommended.

A reliable simulation of the manganese cycle in water supply system is essential for timely and effective manganese treatment strategies. A data-driven model estimating manganese levels in the treated water was developed through a threshold-based approach using raw water and supernatant return manganese levels. This data-driven model and a three-dimensional manganese cycle model for the source reservoir were integrated to simulate the overall manganese variations from the lake to the treated water. A decision support system based on the developed data-driven model was established to allow operators to react to situations that could result in elevated levels of manganese in the treated water. Scenario analyses were completed to examine the manganese variations in the reservoir, raw water and treated water due to different precipitations and wind conditions and to allow the identification of optimal strategies for manganese management from the reservoir to the water supply system.

Advanced oxidation processes, such as using titanium dioxide (TiO2) photocatalysis, are being developed to reduce or eliminate the toxicity of treated water. In this study, the removal of purified anatoxin-a (ANTX-a), live Dolichospermum flos-aquae cells, and a cell extract of this organism under UV-A/TiO2 photocatalysis, creation of decomposition products and their toxicity were investigated. Total degradation of purified ANTX-a from the initial concentration of 10 mg·L−1 with the addition of TiO2 under UV-A irradiation was achieved in 30 min. Under these conditions several decomposition products were noted with m/z ratio from 156.11 to 216.1. Analysis of the completely degraded ANTX-a sample using Thamnotoxkit F™ toxicity test showed that it was no longer toxic. TiO2 photocatalysis was also efficient in the decomposition of the living cyanobacterial cells. Degradation of their cell structures and degradation of released toxin was also achieved in 30 min. Earlier homogenization of cyanobacteria culture significantly accelerated degradation of ANTX-a to 10 min.

Dissolved organic matter (DOM) plays a critical role in determining the quality of wastewater and the safety of drinking water. This is the first review to compare two types of popular DOM monitoring techniques, including absorption spectroscopy and fluorescence excitation-emission matrices (EEMs) coupled with parallel factor analysis (PARAFAC) vs. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), for the applications in wastewater and drinking water treatments. The optical techniques provide a series of indices for tracking the quantity and quality of chromophoric and fluorescent DOM, while FT-ICR-MS is capable of identifying thousands of DOM compounds in wastewater and drinking water at the molecule level. Both types of monitoring techniques are increasingly used in studying DOM in wastewater and drinking water treatments. They provide valuable insights into the variability of DOM composition in wastewater and drinking water. The complexity and diversity of DOM highlight the challenges for effective water treatments. Different effects of various treatment processes on DOM are also assessed, which indicates that the information on DOM composition and its removal is key to optimize the treatment processes. Considering notable progress in advanced treatment processes and novel materials for removing DOM, it is important to continuously utilize these powerful monitoring tools for assessing the responses of different DOM constituents to a series of treatment processes, which can achieve an effective removal of DOM and the quality of treated water.

The present investigation elucidates the effect of different absorbing materials in the single slope solar still (SSSS). The said absorbing materials are Polyvinyl Alcohol (PVA) sponges, pebbles, spherical clay balls (SCB) and CuO nano-coated absorber plates (CuO-NCAP). The experiment has been conducted in the following ways: (i) SSSS with PVA sponges, (ii) SSSS with pebbles, (iii) SSSS with SCB, and (iv) SSSS with CuO-NCAP. This research also investigated the night water collection of all individual experiments. Four identical SSSS were designed with 0.50 m2 collector area each and the four absorber types were tested in the same climatic conditions of Chennai (13.0821°N Latitude & 80.2702°E Longitude) during the period of April to June 2018. Physical and chemical water quality tests were conducted for the feed water (well water) and treated water from the SSSS. The productivity of SSSS-PVA sponges, SSSS-pebbles, SSSS-SCB and SSSS with CuO-NCAP are 1.9 L/m2.day, 2.8 L/m2.day, 2.6 L/m2.day, and 2.9 L/m2.day respectively. The cost of water distilled by SSSS with PVA sponges was approximately $0.0120/L. Similarly, it was $0.0073/L for SSSS with pebbles, $0.0080/L for SSSS with SCB and $0.0077/L for SSSS with CuO-NCAP.

In the present study subsurface flow constructed wetlands treatments (SSFCWT) for the treatment of floriculture industry wastewater in Ethiopia was studied. The objective of the study was to assess the efficiency of SSFCWT in treating floriculture industry wastewater. Seven SSFCW was assessed for physiochemical and heavy metal removal efficiency using standard methods (APHA) and compared to its treatment efficiency. The results showed that treated water quality significantly improved from the inlet to the outlet, with TSS, TDS and TP reduced from 247 ± 0.02 to 31.66 ± 5.8, 391.67 ± 6.18 to 80.66 ± 3.86, 6.7 ± 0.92 to 2.06 ± 0.38, respectively. Similarly, NH 4 + -N, NO 3 -− N, and TN, reduced from 22 ± 2.94 to 9.8 ± 1.96,73.67 ± 4.99 to 27.0 ± 7.12, and 94 ± 4.08 to 38.33 ± 4.11, respectively. The result showed that highest performance variability was observed among the studied SSFCWs. The heavy metal concentration in the influent to effluent for Pb, Cu and Mn was reduced from 0.63 ± 0.09 to 0.36 ± 0.11, 0.49 ± 0.08 to 0.18 ± 0.05 and 0.70 ± 0.07 to 0.43 ± 0.15, respectively. This assessment has proved that a significant reduction of pollutants was observed using SSFCW treatments. There is a need to encourage other floriculture industry to adopt and implement constructed wetland technology as a primary option to protect the environment and public health.

Aromatic hydrocarbons such as 2,4-dichlorophenoxyacetic acid (2,4-D), a common herbicide, is often found in groundwater in areas with intensive agricultural activities. Even in minute concentration, they are known to affect human health. An attempt has been made to capture 2,4-D from aqueous medium using neemoil-phenolic resin treated lignocellulosic jute. Treated jute showed 84% 2, 4-D removal efficiency. The 2,4-D removal of the biosorbent was confirmed from FTIR and 13C NMR analyses. The adsorption process was found to be spontaneous and effective over a pH range between 2 and 8. Maximum 2,4-D removal capacity of treated jute was found to be 38.5 mg/g. Treated jute was found to remove 2,4-D from aqueous media economically and efficiently through polar–polar and non-polar–non polar interactions. No sludge was produced during 2,4-D removal with treated jute nor did the process introduce deleterious characteristics, e.g., hardness and odor to the treated water.

The main purpose of this study was to investigate the effects of a magnetic treatment on the scaling power of hard waters using a non-electrochemical scaling method. The influence of this treatment on the calcium carbonate precipitation was confirmed. Experimental results showed that the scaling potentiality of the treated water was significantly inhibited by the applied magnetic field. The anti-scaling efficiency of the applied permanent magnets was about 45%. The rapid controlled precipitation (RCP) tests confirmed that the magnetic field produces a “memory effect”. The anti-scaling properties of the treated water were retained for approximately three days following the magnetic treatment.

Background Millions of villagers in Bangladesh remain exposed to high levels of arsenic (As) from drinking untreated well-water even though the scale of the problem was recognized 15 years ago. Water treatment at the household-level has been promoted as a viable complement but few longitudinal studies of their efficacy using an objective measure of exposure have been conducted. Participants (N = 622) of a nutrition trial in Araihazar, Bangladesh were each provided with READ-F filters at the beginning of the study and encouraged to use them over the 6 month duration of the intervention. Well-water As, treated water As, and urinary As were monitored periodically during the trial and measured again one year after the trial ended. Results The READ-F filters were initially well received and median urinary As levels for participants declined from 117 μg/L to 51 μg/L within a single week. However, median urinary As levels gradually rose back to 126 μg/L by the end of the trial. Fifty filters were replaced over the course of the trial because of insufficient As removal or reduced flow. With these exceptions, most of the treated water met the WHO guideline for As in drinking water of 10 μg/L. One year after the nutritional trial ended, 95% of participants had abandoned their filter citing inconvenience as the primary reason. At that time, median urinary As levels for 10 participants who had switched to a nearby low-As well had declined to 63 μg/L. Conclusions Participants were probably no longer using the READ-F filter long before the 6 month nutritional intervention ended despite claiming that they were using them. Household-level treatment is likely to continue to play a minor role in the effort to reduce As exposure in Bangladesh. Understanding the limitations of such expensive interventions is important for future policy regarding As mitigation.

Since little is known about the long-run effect of treated water, we examine the educational benefit to rural youth in China from a major water treatment program started in the 1980s. By employing a data set covering two decades and encompassing more than 4700 individuals between ages 18 and 25, we find that, on average, the program increased the completed grades of education of rural youth by 1.1 years. Moreover, the effect was highly heterogeneous across gender and age of exposure. Rural girls benefited from water treatment more than rural boys such that the water treatment program completely eliminated the gender gap in education in treated villages. Young rural people with access to treated water in early childhood experienced significantly higher gains in schooling attainment (i.e., by more than a year) than those that gained access at later stages of life. Our analysis suggests that this program was cost-effective.

The high effectiveness of TiO2-UVA system in bacterial disinfection has gained attention to use this technology in water treatment on different source waters, including desalinated sea water and grey water. However, source waters containing a significant level of bromide could have different chemical pathways during TiO2-UVA disinfection process because reactive bromine species could be formed. To illustrate the water safety from the Br-TiO2-UVA system, this study investigated bacterial inactivation efficiency and disinfection byproduct (DBP) formation under different pH, TiO2 dosages and bromide concentrations in a laboratory setting. At a high bromide concentration (65 mg/L, equivalent to the concentration of natural sea water), the bacterial inactivation rate increased 2 times at pH 5 and more than 5 times at pH 8. However, a significant increase of brominated DBPs, which were considered more carcinogenic and toxic than chlorinated DBPs, was observed. The bacterial inactivation pattern was shifted from the “shoulder-log” to the “log-tail” under different bromide concentrations, suggesting the existence of bromide altered the bacterial inactivation mechanisms. We also observed that the inactivation kinetics of Br-TiO2-UVA system was greatly influenced by water pH. Our laboratory experiments demonstrated that bromide could improve the performance of photocatalytic inactivation, but it also could reduce the water safety by generating a higher level of brominated-DBPs in treated water. Water engineers should pay attention to the brominated DBP formation when applying TiO2-UVA photocatalysis on source waters with a significant level of bromide.