bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disinfection By-Products (DBPs) in Drinking Water from Eight Systems Using Chlorine Dioxide
Authors: Rodriguez Rocio Aranda , Koudjonou Boniface , Jay Brian , LeBel Guy L. , Benoit Frank M. 
Published: May 2018

Abstract
A study was initiated to determine the presence of organic disinfection by-products (DBPs) in drinking water treated with chlorine dioxide (ClO2). One potential advantage for the use of ClO2 as a disinfectant is the reduced formation of organic DBPs. Generally, water treated with ClO2 produces chlorite and chlorate ions, but there is limited information regarding the presence of halogenated organic DBPs. Eight systems that use chlorine dioxide as part of the water disinfection process were investigated. All systems in this study applied chlorine as a primary or secondary disinfectant in addition to ClO2. To evaluate seasonal and spatial variations, water samples were collected during cold water (February to March 2003) and warm water (July to August 2003) months at five sites for each system: raw water (R, before treatment), treated water (T, after treatment but before distribution), and three points along the same distribution line (D1, D2, D3). Sampling and analysis were conducted according to established protocols. A suite of 27 organic DBPs including haloacetic acids (HAA), trihalomethanes (THM), haloacetonitriles (HAN), haloketones, haloacetaldehydes (HA), chloropicrin, and cyanogen chloride were examined. In addition, the concentration of oxyhalides (chlorite and chlorate ions) and auxiliary parameters were also determined.
Chlorite was found in treated (T) and distributed (Dx) waters. The chlorite ion levels decreased along the distribution system (T &gt; D1 &gt; D2 &gt; D3). At T sites, the levels ranged from 10 to 870 µg/L (winter), and from 300 to 1,600 µg/L (summer). Chlorite was not found in treated or distributed water in the one system that used ozone. Chlorate ion levels ranged from 20 to 310 µg/L (winter), and 80 to 318 µg/L (summer). Chlorate levels remained relatively constant throughout the distribution system. THM and eight HAA (HAA8) accounted for approximately 85% of the total DBPs (wt/wt) analyzed, followed by total HA (up to 7%) and HAN (3%). THM in distributed water were found at concentrations between 1.8 and 30.6 µg/L (winter), and 3.3 and 93.6 µg/L (summer). For HAA8, the levels ranged from 13 to 52 µg/L (winter), and 16 to 111 µg/L (summer). Chloral hydrate ranged from 0.2 to 5.2 µg/L (winter), and 0.4 to 12.2 µg/L (summer). The temporal and spatial variations observed in previous studies were confirmed in the current study as well.
Impact of Particulate Matter on Distribution System Disinfection Efficacy
Authors: Wojcicka Linda , Baxter Carole , Hofmann Ron 
Published: May 2018

Abstract
Microorganisms have been shown to survive drinking water disinfection and remain viable in disinfected waters despite the presence of disinfectant residuals. This may be partially attributed to protection by particulate matter. The aim of this study was to determine the effects of the presence of particulate matter on disinfection kinetics. Sphingomonas paucimobilis ATCC 10829 and Helicobacter pylori ATCC 43504 were used in inactivation experiments in the presence and absence of soil, corrosion, and wastewater particles. The results showed that the presence of such particles tended to inhibit chlorine and monochloramine inactivation, although the magnitude of the impact under the conditions tested was small (e.g., 1-log reduction in inactivation for several minutes of contact time in the presence of less than 1 mg/L of disinfectant).
Potato Land Use and Nitrate Runoff Characteristics of Two Subcatchments of the Wilmot River Watershed, Prince Edward Island (PEI), Canada
Authors: Edwards Linnell , Burney Jack R. , Brimacombe Michael , MacRae Allan H. 
Published: May 2018

Abstract
Two subcatchments in the upper reaches of an arable watershed in central Prince Edward Island (PEI), farmed mostly to potatoes (in rotation), were monitored year-round for nitrate runoff. Land management inventories were done every fall and spring and assessed against nitrate runoff through regression analysis for the period 1991 to 2004. Nitrate concentration (averaging approximately 7 mg L-1 over 14 years) in the outflow varied considerably yearly (standard deviation: 2.76) and monthly (standard deviation: 3.43), and exceeded quality guidelines (of 13 mg L-1) for aquatic life in freshwaters at about a 6% frequency, averaging a nitrate-dollar loss of $1.70 per hectare per year.
Quantification of Plant Sterols in Pulp and Paper Mill Effluents
Authors: Mahmood-Khan Zahid , Hall Eric R. 
Published: May 2018

Abstract
Pulp and paper mill effluents (PPMEs) may contain high levels of otherwise naturally occurring organic pollutants such as plant sterols, which are suspected endocrine disrupting chemicals. Exposure to such chemicals may cause various physiological and morphological abnormalities that have been reported in the fish and other aquatic life inhabiting PPME receiving waters. Plant sterols, or phytosterols, form a constituent of wood extractives that may be released into the effluents during the pulping and paper making processes. Isolation and analysis of sterols from the complex mixture of PPMEs is challenging and standard analytical protocols do not exist. The need for having a reliable method for analyzing a particular environmental contaminant such as plant sterols cannot be overemphasized. In the present study a technique was modified for reliable analysis of PPME sterols. The technique involves liquid-liquid extractions using methyl-t-butyl ether and trimethyl-silylation derivatizations of the extracted sterols. Identification and quantification of the PPME sterols were accomplished by gas chromatography and mass spectrometry. Analytical problems were resolved by conducting multiple extractions, drying the sterol extracts, and redissolving and silylating the extracts at an increased derivatization temperature of 70°C. This shortened the suggested incubation period from 12 to 4 h. The modified technique offered improved method sensitivity and reproducibility, and successfully quantified campesterol, β-sitosterol, β-sitostanol, stigmasterol, stigmastanol, cholesterol, and ergosterol in PPMEs. Primary and secondary treated PPMEs analyses suggested 800 ± 190 µg/L total sterols in primary effluents, and 211 ± 90 µg/L in biologically treated final effluents. β-Sitosterol, β-sitostanol, and campesterol alone accounted for about 80% of the total sterols. A general comparison of the sterols in primary and secondary effluents suggested about 73% removal across the secondary treatment systems sampled.
Study on the Performance of an Anoxic Biotrickling Filter for the Removal of Hydrogen Sulphide from Biogas
Authors: Soreanu Gabriela , Falletta Patricia , Béland Michel , Edmonson Kara , Seto Peter 
Published: May 2018

Abstract
The paper presents aspects related to the performance of an anoxic biotrickling filter designed for hydrogen sulphide (H2S) removal from biogas. In this process, nitrate was supplied through a nutrient solution as an electron acceptor for anoxic growth of H2S-oxydizing microorganisms. The biotrickling filter's packing media consisted of a layer of plastic fibres over volcanic rocks in a ratio 0.78:1 by volume. The total volume of packing media was 0.014 m3. Several H2S loading rates (IL) were tested under continuous dynamic conditions, ranging between 20 and 550 g of H2S feed/(m3bed·day). Maximum process performance (&gt;95%) was observed for IL ranging up to approximately 300 g of H2S feed/(m3bed·day). The degradation of hydrogen sulphide occurred with the formation of both sulphate and elemental sulphur, their formation ratio being dependent on H2S loading rate. Elemental sulphur was found to be the dominant degradation product, particularly at IL &gt; 96.18 g of H2S feed/(m3bed·day). The use of two biotrickling filters in series was also tested, and a significant improvement in process performance was observed. This technology allows simple operation with low maintenance and has the potential for sulphur recovery.
Evaluation of Plantain Peelings Ash Extract as Coagulant Aid in the Coagulation of Colloidal Particles in Low pH Aqua System
Authors: Oladoja Nurudeen A. , Aliu Yekini D. 
Published: May 2018

Abstract
The use of plantain peelings ash extract (PPAE) as a coagulant aid in a low pH water was evaluated in the present studies. Plantain peelings were collected, washed, dried, and ashed in a furnace. The ash was extracted using deionized water, and the chemical composition was examined using an atomic absorption spectrophotometer. Synthetic turbid water of varying turbidities (50, 100, 300 NTU) and varying pHs (2, 3, 4) were prepared by clay dispersion in deionized water. The optimum alum dosages for the coagulation of colloidal particles in different turbid waters of varying pHs were determined by method of continuous variation using the jar test procedure. The residual turbidities of the treated waters were determined, and the alum doses that gave the minimum residual turbidities were taken as the optimum dosage for the removal of colloidal particles. The use of PPAE as a coagulant aid with alum showed an improvement in the value of residual turbidities of the treated waters. Results obtained from the different studies showed that treated waters of lower residual turbidities were obtained from synthetic waters of higher initial turbidities and pHs. The pH of the treated water decreased with an increase in alum dosage, whereas an increase in the pH value was observed with the addition of PPAE as a coagulant aid. High correlation coefficient values (r2) were obtained when the changes in pH (i.e., ΔpH = pHf –pHi) of the treated waters were correlated with alum and PPAE additions, and mathematical relationships were derived from the linear graph. Studies on the effect of flocculation time on residual turbidity showed that an optimum flocculation time of 30 minutes was attained, when alum was used alone, before redistribution and redispersion of the flocs was noticed. This phenomenon did not occur when PPAE was used as a coagulant aid.
Swimming in Sewage: Indicators of Faecal Waste on Fish in the Saint John Harbour, New Brunswick
Authors: Loomer Heather A. , Kidd Karen A. , Vickers Tim , McAslan Alison 
Published: May 2018

Abstract
Despite increased recognition of the risks to the health of humans and the environment, untreated municipal wastewaters are still discharged into waterways worldwide. One of the primary concerns related to its discharge into surface waters is the risk to human health through the transmission of pathogens associated with faecal matter. Saint John, New Brunswick, is one of the few Canadian cities that still releases untreated sewage into its urban waterways and harbour. Water faecal coliform levels, an indicator of faecal waste and associated pathogens, are well above recreational guidelines in some of these areas. Although it is not encouraged by the municipality, recreational fishing occurs in these areas and this raises concerns regarding the potential for disease transmission during the handling of these fish. To investigate the potential for fish to be a vehicle of pathogen transmission to humans, the skin of wild fishes (smelt, Osmerus mordax, and mummichog, Fundulus heteroclitus) and caged mummichog was sampled for faecal coliforms from several sites in Saint John between August and November of 2005. Water faecal coliform levels at sites used for caging studies and wild fish collections, and the duration of caging were compared with the number of faecal coliforms on the surface of the fish. Skin samples from the two fish species collected from the wild indicated elevated levels of fecal coliforms in some locations. Both wild and caged fish showed that the amount of faecal coliform on fish skin is influenced by the water faecal coliform levels.
Evaluation of Mitigation Methods to Manage Contaminant Transfer in Urban Watersheds
Authors: Brydon Julia , Oh Iwata , Wilson Julie , Hall Ken , Schreier Hans 
Published: May 2018

Abstract
Three case studies on trace metal contamination in urban stormwater are presented from the Greater Vancouver area of British Columbia. In the first case study, the spatial and temporal variability in trace metals in sediments were determined in the completely urbanized Brunette watershed. A natural lake in the middle of the watershed acts as a sediment detention system, and an analysis of the sediment core showed the historic accumulation of metal and selective organic contaminants in sediments since the early 1800s. Suspended sediments transported during storm events showed significantly higher concentrations of trace metals than bedload sediments, and the largest proportion of the geochemically active metals was found to be associated with the organic-sulphur-based fraction. Benthic organism survival tests showed mixed results with lower survival and growth in urban sediments than in control sediments from a forested watershed. In the second case study, significant correlations were obtained between percent impervious cover and trace metal concentrations in 28 subwatersheds with various degrees of urbanization. It is shown that imperviousness combined with traffic density can significantly improve the prediction of metal contamination in highly urbanized watersheds. In the third case study five urban stormwater detention systems were examined over one year to determine how effective these systems were in removing metal contamination. The results were highly variable depending on a wide range of physical conditions, land use activities, traffic volume, and detention system designs. The range of total metal detention was between −15 to +72% for copper (Cu), lead (Pb), and zinc (Zn), while iron (Fe) and manganese (Mn) retention was generally poor. Labile Zn was more effectively retained in four of the five ponds, and a significant relationship was found between percent imperviousness, traffic volume, and Zn concentrations in water, sediment, and labile form.
Culex Mosquitoes, West Nile Virus, and the Application of Innovative Management in the Design and Management of Stormwater Retention Ponds in Canada
Authors: Jackson Michael J. , Gow Jennifer L. , Evelyn Michelle J. , Meikleham Neil E. , McMahon T.J. Scott , Koga Erin , Howay Tim J , Wang Laura , Yan Evan 
Published: May 2018

Abstract
Stormwater best management practices have helped to address environmental concerns regarding peak water flows and accumulation of sediment and contamination by pollutants, but often overlook potential public health repercussions such as creating habitat for virus-carrying mosquitoes. Retention ponds frequently hold standing water for more than two weeks during the mosquito breeding season, creating development habitat for the aquatic stages of West Nile virus vectors. To avoid this problem, knowledge of vector ecology should be incorporated in the design of best management practices and integrated stormwater management plans. An integrated approach that incorporates hydrological management of water depth, flow, and surface agitation combined with manipulation of native biota and habitats based on the unique ecology and behaviour of the vector species can deter egg-laying mosquitoes by mimicking natural processes. Such an approach could help prevent disease transmission and alleviate the need for widespread application of pesticides.
Field Evaluation of Long-Term Performance and Use of Biosand Filters in Posoltega, Nicaragua
Authors: Vanderzwaag Jason C. , Atwater James W. , Bartlett Karen H. , Baker Derek 
Published: May 2018

Abstract
An evaluation was conducted in 2007 on biosand filters that were installed in Posoltega, Nicaragua in 1999 and 2004.The objectives were to characterize the condition and use of filters eight and three years after installation, determine filter performance of those filters still in use, and identify determinants of successful long-term use and performance. Methods consisted of household identification, user questionnaires, and water quality testing. Of the 234 filters installed, only 24 were found to still be in use. Average log reductions were 1.73 (98%) for total coliforms, 1.36 (96%) for Escherichia Coli, and 0.91 (88%) for turbidity. Statistically significant effects were detected for the magnitude of the contamination of source water, the peak hydraulic loading rate, and the standing depth of water over the filter media. Questionnaire results indicated user training on filter maintenance could improve the peak hydraulic loading rate and hence filter performance. The low rate of sustained use (10%) is an indication of failed implementation, and is attributable to structural failure, particularly cracking of the concrete filters from 2004. Nonetheless, this evaluation demonstrated the biosand filter technology to be robust since those filters still in use were performing as expected three and eight years postimplementation.
Evaluation of Field Testing Techniques Used in a Household Water Treatment Study in Posoltega, Nicaragua
Authors: Vanderzwaag Jason C. , Bartlett Karen H. , Atwater James W. , Baker Derek 
Published: May 2018

Abstract
A field evaluation of biosand filters, a method of household water treatment, was conducted in Posoltega, Nicaragua. The evaluation consisted of water quality testing for Escherichia coli and total coliforms using membrane filtration (MF) with m-coliBlue24 growth media, and SolarCult dipslides. For each sample tested, the MF procedure was applied to two volumes differing by an order of magnitude to capture the expected range of microbial contamination. A follow-up laboratory quality assurance/quality control procedure was undertaken to validate the field methods. The average coefficient of variation was 51%, with no statistically significant difference between the field and laboratory data. The MF procedure used with m-coliBlue24 produced useful reproducible results for the microbial concentrations encountered in the field. Dipslide results were found to correlate poorly to the membrane filtration results from the field, and should not be used to test drinking water due to the high limit of detection. They may still be useful for preliminary testing of highly contaminated source water as part of a household water treatment project. Dipslides may also be a useful tool for local health representatives to promote safe water practices within the community since they are simple to use and provide a visual indicator of water quality.
Heavy Metals Removal by Hydroxide Precipitation and Coagulation-Flocculation Methods from Aqueous Solutions
Authors: Pang Fong Moi , Teng Sheau Ping , Teng Tjoon Tow , Omar A.K. Mohd 
Published: May 2018

Abstract
The hydroxide precipitation and coagulation-flocculation methods were used to treat wastewater containing lead, zinc, copper, and iron. The concentrations of heavy metals in the synthetic wastewater range from 1 to 14 mg/L for lead, 5 to 90 mg/L for zinc, 3 to 90 mg/L for copper and 5 to 45 mg/L for iron. Individual Zn(II) and Cu(II) with concentrations below 90 mg/L and Fe(III) with concentrations below 45 mg/L were removed up to 99% by the precipitation method in the pH range of 8.7 to 9.6, 8.1 to 11.1, and 6.2 to 7.1, respectively. Though the highest percent removal of Pb(II) by hydroxide precipitation alone was approximately 98%, the final dissolved concentrations did not fulfill the Standard A discharge limit required by the regulations, thus further treatment by the coagulation-flocculation process was performed. Aluminum sulphate (alum), polyaluminum chloride (PACl) and magnesium chloride (MgCl2) have been used as coagulants together with Koaret PA 3230 as coagulant aid to determine the effectiveness of the coagulation method for the removal of individual heavy metals in the wastewater. The effects of parameters such as pH, type, and dosage of coagulant on the percentage of metal removal, and the amount of coagulant aid on the flocs settling time were investigated. The jar test showed that up to 99% removal of Pb(II) was attained by the addition of 1,200 mg/L of alum, 150 mg/L of PACl, and 2,000 mg/L of MgCl2 in a pH range of 6.5 to 7.8, 8.1 to 8.9, and 9.7 to 10.9, respectively.
Assessment of Northern Mummichog (Fundulus heteroclitus macrolepidotus) as an Estuarine Pollution Monitoring Species
Authors: Finley Megan A. , Courtenay Simon C. , Teather Kevin L. , van den Heuvel Michael R. 
Published: May 2018

Abstract
The use of multiple spawning fishes in environmental effects monitoring programs has proven difficult for a number of reasons including the inability to predict reproductive investment and ensure synchronous sampling of reference and impacted populations. The estuarine resident northern mummichog (Fundulus heteroclitus macrolepidotus) has been successfully used as a sentinel for effects of pulp and paper mill effluents in Atlantic Canada and has been proposed for monitoring other anthropogenic impacts. This study investigated the spatial and temporal variability of the somatic parameters used to describe fish performance, specifically measures of energy use and storage, in estuaries located in Prince Edward Island, Canada. Three sites with varying levels of agricultural input were studied. Fish at all sites depleted their energy reserves over winter, as reflected in depressed condition, liver size, and gonad size, but then quickly replenished them in May. These population parameters were highly variable throughout the reproductive season and within an estuary. Spawning was continuous at all sites without indication of lunar or other periodicity. We conclude that repeated sampling is required to assess reproductive output in the northern mummichog and densities of adults and young-of-the-year deserve further investigation as a potentially less logistically demanding indicator of eutrophication.
Combined Treatment of Domestic Wastewater using Anaerobic and Solar Photocatalytic Treatment
Authors: Banu J. Rajesh , Kaliappan Sudalyandi , Do Khac-Uan , James Arthur , Yeom Ick Tae 
Published: May 2018

Abstract
The present study utilizes anaerobic and solar photocatalytic methods to treat domestic wastewater. For stage I, a granulated hybrid upflow anaerobic sludge blanket reactor (HUASB) with a working volume of 5.9 L was used. It was run in a recirculation mode for 3 days called "one cycle," and 30 cycles were run to find out the stability of the anaerobic treatment. During stage I anaerobic treatment, 90% of the chemical oxygen demand (COD) was removed, and it increased with an increase in digestion period for each cycle. Volatile fatty acids did not cause any operational problems during the stage I anaerobic treatment, being in the range of 280 to 90 mg/L. Stage I treated wastewater was subjected to a stage II solar photocatalytic oxidation method. The optimum pH and catalyst loading for the solar photochemical oxidation were found to be 5 and 200 mg/L, respectively. Stage II, treatment at an optimized condition, removed 66% of organics from the stage I treated wastewater. The combined COD removal due to the combination of these two technologies was found to be 96%.