bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pharmaceuticals in the Yamaska River, Quebec, Canada
Authors: Yargeau Viviane , Lopata Antonina , Metcalfe Chris 
Published: May 2018

Abstract
Pharmaceutically active compounds have been detected in North America and Europe in groundwater, surface water, wastewater, and drinking water. In the province of Quebec in Canada, there has been little data to assess the occurrence of pharmaceutical residues in the aquatic environment. In August of 2005, samples of surface water were collected at 10 sites along the Yamaska River basin in Quebec, which passes through important agricultural areas and receives wastewater from several urban centers with populations ranging up to 44,000 residents. Several acidic drugs (naproxen, ibuprofen, gemfibrozil), neutral drugs (caffeine, carbamazepine, cotinine), and the sulfonamide antibiotic sulfamethoxazole were detected in the majority of the surface water samples. The antidepressant fluoxetine (neutral/basic drug) was not detected in any samples, while acetaminophen (acidic drug) was detected at only two sites, and sulfapyridine (sulfonamide antibiotic) was detected at only one site. Sulfamethoxazole and carbamazepine were present at the highest maximum concentrations of 578 ng/L and 106 ng/L, respectively. The concentrations of most of the target pharmaceutically active compounds observed in surface water samples within the watershed were generally consistent with the number of people in urban centers near the sampling sites when compared with other studies in urban watersheds. However, carbamazepine, naproxen, and sulfamethoxazole were present at surprisingly high concentrations for some of the low density areas. Overall, these results demonstrate that pharmaceuticals are distributed in surface waters within a watershed in Quebec at concentrations similar to levels observed in previous studies done in other parts of North America.
Low-Nitrate-Days (LND), a Potential Indicator of Cyanobacteria Blooms in a Eutrophic Hardwater Reservoir
Authors: Nürnberg Gertrud K. 
Published: May 2018

Abstract
When nitrate was low in a hypereutrophic, hardwater reservoir, cyanobacteria proliferated into blooms. Based on this observation an index was developed that relates an easily measurable variable, the period of Low-Nitrate-Days (LND), to the period when nuisance cyanobacteria (blue-greens) proliferate and “bloom”. The bloom indicator LND (d·yr-1) was defined as the period of time during summer and early fall when nitrate concentration is below a lake-specific threshold. This concept was valuable in Fanshawe Lake, a southern Ontario reservoir of the Thames River in the Lake Erie catchment basin, where traditional bloom indicators are rare. A nitrate threshold of 1 to 2 mg·L-1 is supported by occasional observations of chlorophyll (Chl) concentration, blue-green biomass, visual inspection, and photographic documentation. Fanshawe Lake's water quality (phosphorus, Chl, and Secchi disk transparency) varied from summer to summer and LND ranged from 0 to 175 d·yr-1 with a long-term average of 62 d·yr-1 for 38 years. LND was positively and significantly correlated with average summer total phosphorus concentration (available for 8 years), but not Chl (n = 6) nor transparency (n = 11), possibly because of an invasion by the zebra mussel Dreissena. LND values agreed well with cyanobacteria biomass indicators predicted from other models. Significant relationships with 38 years of flows and the climatic index (winter North Atlantic Oscillation) reveal that during high-flow years estimated cyanobacteria blooms are infrequent, while during low-flow years bloom periods are extended and the water quality is poor. Investigations on other man-made lakes and river sections of the Thames River, and preliminary studies on natural lakes with differing trophic states show that LND may be a useful variable in all lakes and reservoirs where nutrient limitation switches from phosphorus to nitrogen during summer.
Selecting Water Disinfection Processes using Fuzzy Synthetic Evaluation Technique
Authors: Chowdhury Shakhawat , Champagne Pascale 
Published: May 2018

Abstract
Drinking water treatment strategies generally involve treatment processes such as screening, coagulation/flocculation, sedimentation, and filtration/adsorption followed by disinfection. Disinfection approaches include chlorine/chlorine (chloramine), granular activated carbon with post chlorine (chloramine), ozone/chlorine (chloramine), chlorine dioxide/ chlorine (chloramine), chloramine/chloramine, and ultraviolet radiation/chlorine (chloramine). However, comparative evaluation of these disinfection methodologies and their application to a particular source of water is rare. In this study, a framework for multicriteria decision making has been developed. Human health risk, cost, technical feasibility, and disinfection performance have been incorporated as the criteria for evaluation of the disinfection approach. A fuzzy synthetic evaluation technique has been incorporated where fuzzy triangular membership functions were developed to capture the uncertainties of the basic attributes. This paper compares three disinfection approaches: chlorination, granular activated carbon with post chlorination, and chloramination through a multistage hierarchy risk management model in which the analytical hierarchy process has been used to determine the relative importance of various attributes at different hierarchy levels. The evaluation process was found to be sensitive to the assignment of relative importance of the attributes. Chlorination was evaluated as the best disinfection approach in most of the cases.
Synergistic Benefits Between Ultraviolt Light and Chlorine-Based Disinfectants for the Inactivation of Escherichia coli
Authors: Rand Jennie L. , Shupe Gordon , Gagnon Graham A. 
Published: May 2018

Abstract
Ultraviolet light is increasing in popularity as a primary disinfectant in drinking water treatment because of its effectiveness against chlorine-resistant pathogens and lack of disinfection by-product (DBP) formation. Previous bench-scale studies have shown that there are possibly synergistic benefits in reducing heterotrophic bacteria when ultraviolet (UV) light is coupled with chlorine (Cl2) or monochloramine (NH2Cl). Additional experiments have demonstrated that synergy exists between various disinfectants in controlling numerous bacteria, viruses, and protozoan. Few studies, to date, have specifically investigated synergy with UV in combination with chlorine-based drinking water disinfectants including chlorine dioxide (ClO2), Cl2, and NH2Cl. This preliminary study looked at the effectiveness of seven disinfection strategies (UV, Cl2, ClO2, NH2Cl, UV/Cl2, UV/ClO2, and UV/NH2Cl) against Escherichia coli in a single-species system at various combinations of disinfectant dose and contact time. Spiked solutions containing E. coli were treated by UV alone, chemical disinfectant alone, or UV coupled with chemical disinfectant. It was found that the combined disinfection strategies achieved the highest removal. Data were additionally analyzed for synergistic benefits, and each combination had a positive result. Results suggest that drinking water utilities may see enhanced removal of bacteria and potentially other pathogens due to synergistic benefits when UV was used in combination with any chlorine-based disinfectant. However, more data are required to conclusively determine synergistic relationship(s) between UV light and chlorine-based disinfectants.
Inactivation of the Bacteriophage MS2 by the Ciliated Protozoan, Tetrahymena thermophila
Authors: Pinheiro Marcel D.O. , Power Mary E. , Butler Barb J. , Dayeh Vivian R. , Slawson Robin , Lee Lucy E.J. , Lynn Denis H. , Bols Niels C. 
Published: May 2018

Abstract
Because the range of biological mechanisms responsible for the inactivation of viruses in man-made and natural water systems is poorly understood, the involvement of the free-living ciliated protozoan, Tetrahymena thermophila, in viral inactivation was investigated. The ciliate was found to remove the bacteriophage MS2 when the phage and ciliate were co-incubated in a simple salt solution. MS2 was enumerated as plaque forming units (pfus). MS2 removal was achieved only by living and not formalin-fixed ciliates, and was blocked by treatments that impaired the formation of food vacuoles. These treatments were cytochalasin B and low temperature. When fluorescently labelled with SYBR gold prior to co-incubation, MS2 were seen inside Tetrahymena within vesicles that had the shape and size of food vacuoles. The number of pfus associated with Tetrahymena was low. This suggests that the engulfment of the phage into food vacuoles led to the inactivation of MS2, which is frequently used as a surrogate for poliovirus in environmental microbiology. In the future, a broader understanding of the capacity of ciliates to inactivate viruses could lead to methods for improving water quality through the manipulation of ciliate populations and activities.
An Assessment of Environmental Changes in Three Lakes from King's County (Nova Scotia, Canada) Using Diatom-Based Paleolimnological Techniques
Authors: Thienpont Joshua R. , Ginn Brian K. , Cumming Brian F. , Smol John P. 
Published: May 2018

Abstract
Paleolimnological approaches using sedimentary diatom assemblages were used to assess water quality changes over the last approximately 200 years in three lakes from King's County, Nova Scotia. In particular, the role of recent shoreline development in accelerating eutrophication in these systems was assessed. Sediment cores collected from each lake were analyzed for their diatom assemblages at approximately 5-year intervals, as determined by 210Pb dating. Analyses showed that each system has changed, but tracked different ecosystem changes. Tupper and George lakes recorded shifts, which are likely primarily related to climatic warming, with diatom assemblages changing from a preindustrial dominance by Aulacoseira spp. to present-day dominance by Cyclotella stelligera. In addition to the recent climatic-related changes, further diatom changes in the Tupper Lake core between approximately 1820 and 1970 were coincident with watershed disturbances (farming, forestry, and construction of hydroelectric power infrastructure). Black River Lake has recorded an increase in diatom-inferred total phosphorus since about 1950, likely due to impoundment of the Black River system for hydroelectric generation and subsequent changes in land runoff. Before-and-after (i.e., top-bottom) sediment analyses of six other lakes from King's County provided further evidence that the region is being influenced by climatic change (decreases in Aulacoseira spp., increases in planktonic diatom taxa), as well as showing other environmental stressors (e.g., acidification). However, we recorded no marked increase in diatom-inferred nutrient levels coincident with shoreline cottage development in any of the nine study lakes. Paleolimnological studies such as these allow lake managers to place the current limnological conditions into a long-term context, and thereby provide important background data for effective lake management.
Spatial Distribution and Characterization of Contaminated Soils in Riverbanks of Saint-François and Massawippi Rivers (Southern Québec)
Authors: Saint-Laurent Diane , Hähni Marlies , St-Laurent Julien 
Published: May 2018

Abstract
Des sols contaminés aux hydrocarbures (C10-C50) et d'autres contaminants ont été découverts récemment dans les berges des rivières Saint-François et Massawippi, entre les municipalités de Eustis et Drummondville (sud du Québec). Il est probable que cette contamination provienne d'un déversement accidentel ou illégal dont la source serait l'ancienne mine de Eustis située au abord de la rivière Massawippi. La couche contaminée se retrouve parfois à plus d'un mètre de profondeur des berges. Malgré qu'il existe de nombreux rapports gouvernementaux sur la qualité de l'eau de ce bassin, aucune étude sur la contamination des berges et des sédiments du lit n'a été réalisée le long des rivières Saint-François et Massawippi, même si ces rivières circulent à travers d'anciennes zones industrielles et minières. Cette étudie vise à évaluer la distribution spatiale de la contamination le long des berges et dresse une caractérisation du type et du niveau de concentration des hydrocarbures et autres contaminants (ex. métaux lourds). Les résultats obtenus indiquent que certaines berges sont davantage contaminées par des hydrocarbures (C10-C50), en particulier dans le secteur de Windsor. Les autres polluants (métaux lourds, BPC et HAP) indiques des faibles niveaux de contamination à l'exception de certains métaux (Cu et Zn). Pour les sites plus pollués, ils sont inclus dans les critère B et C qui présente certaines contraintes d'utilisation du sol en tenant compte des normes du Ministère du Développement durable, de l'Environnement et des Parcs.
Transport of Lithium Tracer and E. coli in Agricultural Wastewater Treatment Wetlands
Authors: Boutilier Leah , Jamieson Rob , Gordon Robert , Lake Craig 
Published: May 2018

Abstract
Agricultural waste must be managed effectively to protect surface and groundwater resources, as well as human health. Constructed wetlands can provide a low-cost environmentally acceptable method for the treatment of agricultural wastewater. An ionic tracer (Lithium chloride [LiCl]) and a biotracer (a naladixic acid-resistant strain of Escherichia coli) were injected into six pilot-scale constructed wetlands treating dairy wastewater: three surface-flow (SF) wetlands and three subsurfaceflow (SSF) wetlands. Each wetland was 3.9-m long and 1.7-m wide. Residence time distribution functions were calculated for each wetland to investigate the hydraulic behaviour of each system during winter and summer conditions. During the summer study, the mean residence times for SF wetlands 2, 4, and 6 were 12, 16, and 14 days, respectively, while the mean residence time for SSF wetlands 1, 3, and 5 were 23, 18, and 22 days, respectively. The longitudinal dispersion coefficients were in the order of 10-6 m2 s-1 for each wetland during the summer and winter. The mean residence time for SF wetlands 2, 4, and 6 during the winter study were 8, 10, and 10 days, respectively, while the mean residence time for SSF wetlands 1, 3, and 5 were 8, 9, and 10 days, respectively. E. coli effluent peaks often occurred prior to Li peaks, suggesting that bacteria may be motile within the wetland environment. This study suggests that dispersion is an important mass transport process in both SF and SSF wetlands. Long-term operation of SF and SSF treatment wetlands may cause reduced retention times and treatment efficiency due to organic matter accumulation and channelling. Cold winter temperatures may also increase the survival of bacteria within treatment wetland systems, decreasing the wetland's ability to reduce bacteria concentrations during the winter months.
Application of SCR Technology for Degradation of Reactive Yellow Dye in Aqueous Solution
Authors: Dehghani Mohammad Hadi , Mesdaghinia Ali Reza , Nasseri Simin , Mahvi Amir Hossein , Azam Kamal 
Published: May 2018

Abstract
The effect of sonochemical reactors (SCR) technology upon the degradation of reactive yellow dye has been studied and reported here. Sonochemical reactors (ultrasound irradiation) produce strong cavitation in aqueous solution causing shock wave and reactive free radicals by the violent collapse of the cavitation bubble. These effects should contribute to destruction as well as the decomposition of dyes. This research investigated the efficacy of sonochemical reactors for decolourizing reactive yellow dyes in aqueous solution. In this research, the influence of concentration, frequency, treatment time, and reactor power on the dye decomposition were investigated. The results obtained from the study carried out have shown that SCR can be used effectively for degradation of reactive yellow dyes. The results suggested sonochemical reactors provided maximum destruction, and 120 min treatment time at 130 kHz and 500 W were the most effective for the maximum degradation of reactive yellow dye.
Concentrations of Endotoxins in Waters Around the Island of Montreal, and Treatment Options
Authors: Gehr Ronald , Uribe Santiago Parent , Da Silva Baptista Isabel Fatima , Mazer Bruce 
Published: May 2018

Abstract
Endotoxins are a component of most Gram negative bacteria, and some cyanobacteria. They may be toxic to humans when inhaled or injected, but the effects are unclear when they are ingested. In fact, low concentrations may protect children against certain allergies. Data for endotoxins in Quebec waters are unavailable, hence this study mapped levels in the waters around Montreal, using two commercial test methods. The recently developed factor C method had a greater linear range and was more convenient to use than the widely used Limulus amebocyte lysate (LAL) method. Although the methods gave endotoxin values of the same order, a consistent relationship between the two could not be established. Endotoxin concentrations in the untreated waters varied from 32 to 1,188 EU/mL, comparable in the literature from pristine waters to wastewaters. Values were generally lower in the summer. Filtration is known to be partially effective at removing endotoxins, but the effects of disinfection are not well established. Accordingly, chlorination, ozonation, and ultraviolet light were tested for the destruction of endotoxins in water, at doses found during drinking water disinfection. While chlorine and ultraviolet light had minimal effects on endotoxin levels, ozone could achieve up to 60% reductions at Ct values (concentration x contact time) as low as 2.5 mg•min/L.
Influence of Polymer Selection on Nutrient Phase Separation for Waste Activated Sludge Thickening at Bench Scale
Authors: MacDonald Allan J. , Basu Onita D. 
Published: May 2018

Abstract
The use of polymers to condition waste activated sludge prior to thickening is a common practice at domestic wastewater treatment plants. In this study, the performance of various commercially available granular polymers was observed. Thickening by gravity belt thickener was simulated at the bench scale, and the thickened sludge and filtrate produced were examined. Laboratory analysis was used to determine the differences in nutrient chemical concentration in the thickened solids and filtrate produced by different polymers. By examining the content of nutrient chemicals such as total Kjeldahl nitrogen (TKN), ammonia nitrogen, and total phosphorous, this research showed that polymer choice could affect the chemical composition of thickened sludge and filtrate with respect to nutrients. Results showed that the total phosphorous and TKN concentrations in the thickened sludge and filtrate were affected by polymer selection, which suggested that the chemical loading on the plant due to filtrate recycle, and the nutrient content of thickened sludge delivered to the digester are affected by polymer choice. Polymer optimization studies that examine nutrient properties of filtrate and thickened sludge beyond the basic total suspended solids analysis may be advantageous to minimize recycling of these compounds into the filtrate phase.
Filtration du bleu de méthylène, du chrome hexavalent et de l'acide éthylène diamine tétracétique sur une membrane céramique d'ultrafiltration à base de ZnAl2O4−TiO2
Authors: Chahid El Ghaouti , Loukili Hayat , Tahiri Soufiane , Younssi Saâd Alami , Majouli Abdelhak , Albizane et Abderrahman 
Published: May 2018

Abstract
Dans ce travail, nous avons étudié la rétention du bleu de méthylène (BM), du chrome hexavalent Cr(VI) et de l'acide éthylène diamine tétracétique (EDTA) par une membrane ZnAl2O4−TiO2. Les résultats obtenus ont montré que cette membrane présente une charge résiduelle qui dépend fortement du pH. L'effet de la pression et de la concentration sur le taux de rejet des espèces filtrées est étudié. La rétention des espèces ioniques est due à un mécanisme fondé sur les interactions électrostatiques entre les charges portées par la membrane et les ions. Le taux de rejet du BM diminue avec l'augmentation du pH, une situation qui provoque une diminution progressive de la charge positive de la membrane. Dans le cas du Cr(VI) et de l'EDTA, un pH alcalin est favorable pour une bonne rétention car la charge membranaire devient moins positive, le chrome est sous forme de CrO42− et l'EDTA apparaît sous ses formes les plus anioniques. L'effet de la pression sur le taux de rejet des solutés a montré que la contribution convective domine aux fortes pressions et conduit à des rétentions maximales du fait que le flux convectif du solvant Jv augmente et vient diluer le perméat.
A New Approach in Measuring Rainfall Interception by Urban Trees in Coastal British Columbia
Authors: Asadian Yeganeh , Weiler Markus 
Published: May 2018

Abstract
Interception loss plays an important role in controlling the water balance of a watershed, especially where urban development has taken place. The aim of this study was to illustrate the importance of urban trees as a form of ‘green infrastructure’ where they reduce stormwater runoff and rainwater intensity. In addition, trees cause a delay in precipitation reaching the ground. Interception loss was studied in the North Shore of British Columbia. We applied a unique methodology for measuring throughfall under six different urban trees using a system of long polyvinyl chloride pipes hung beneath the canopy capturing the throughfall and draining it to a rain gauge attached to a data logger. Different tree species (Douglas-fir [Pseudotsuga menziesii] and western red cedar [Thuja plicata]) in variable landscape sites (streets, parks, and natural forested areas) and elevations were selected to ensure that the system adequately captured the throughfall variability. Interception and throughfall were monitored over a one year cycle for which the results of seven discrete storm events for coniferous trees from the District of North Vancouver during 2007 to 2008 are presented. Cumulative gross precipitation for seven selected events was 377 mm. Average canopy interception during these events for Douglas-fir and western red cedar were 49.1 and 60.9%, where it corresponded to average net loss of 20.4 and 32.3 mm, respectively. The interception loss varied depending on canopy structure, climatic conditions, and rainfall characteristics.
Characteristics of Sediment Removal in Two Types of Permeable Pavement
Authors: Brown Chris , Chu Angus , van Duin Bert , Valeo Caterina 
Published: May 2018

Abstract
This study investigates the processes and characteristics of solids removal in two types of permeable pavement: UNI Eco-Stone and porous asphalt. The mechanisms and processes behind solids removal within permeable pavement structures was studied for these two types of permeable pavements using both field installations and laboratory experiments. Results from the study showed that both pavement types are capable of excellent total suspended solids removal, in the range of 90 to 96% removal of solids from influent. Particle size distribution analysis of accumulated sediment within the pavement structure and in the influent and effluent showed that the particles in the effluent of the pavements are substantially finer than that in the influent. Laboratory results involving no crust formation indicated that, although solids removal occurs throughout the entire structure, the "sieving action" occurs primarily at the geotextile interface.