bluuebunny/crossref_metadata_2025_split huggingface dataset:
Occurrence of Polycyclic and Nitro Musk Compounds in Canadian Sludge and Wastewater Samples
Authors: Lee Hing-Biu , Peart Thomas E. , Sarafin Kurtis 
Published: May 2018

Abstract
Fragrances such as synthetic musk compounds are commonly used as additives in a wide range of consumer and personal-care products. At the end of their life cycle, most of these compounds will end up in municipal sewage systems. In this work, we report the occurrence of selected polycyclic and nitro musk compounds in sewage sludge, influent, effluent, as well as some industrial wastewater samples collected in Canada. A newly developed supercritical carbon dioxide extraction technique was used for the extraction of residual musk fragrances in the sludge. Final analysis was performed by gas chromatography/ mass spectrometry (GC/MS) using electron-impact and methane negative ion chemical ionization techniques. The results indicated that Galaxolide® (HHCB), Tonalide® (AHTN), musk xylene (MX), and musk ketone (MK) were the most common musk compounds in the Canadian environment, as they were found in every sample in this study. In the same sludge sample, levels of HHCB and AHTN (ranging from 1.3 to 26.7 μg/g) were often found to be about 1000 times higher than those of MX and MK (ranging from 1.4 to 422 ng/g). Similarly, in the sewage influent and effluent collected in Ontario, the levels of HHCB and AHTN (ranging from 159 to 2411 ng/L) were much higher than those of MX and MK (ranging from 1 to 84 ng/L). The levels of musk compounds varied widely in industrial wastewaters. In one sample collected from a detergent manufacturer, the levels of HHCB, AHTN, MX, and MK were found to be 54,200, 13,300, 5480, and 2.2 ng/L, respectively. It was also noted that the levels of MX and MK observed in the samples collected from the commercial laundries in Toronto were significantly higher than those found in domestic sewage.
Efficiency of Packed Cage RBC System for Treatment of Wastewater Containing Surfactants
Authors: Sirianuntapiboon Suntud , Srikattanaprom Panthong 
Published: May 2018

Abstract
The chemical oxygen demand (COD) and five-day biological oxygen demand (BOD5) removal efficiencies of a packed cage rotating biological contactor (RBC) system under a hydraulic retention time (HRT) of 16 h declined from 93.90% to 78.58% and 78.61% and 96.27% to 84.83% and 87.93%, respectively, with an increase of sodium dodecyl sulphate (SDS) and triton X-100 loading from 0.00 to 1.25 mg/m2·d. Reactor no. 1 of the system changed to anaerobic when the system was operated under an HRT of 8 h with surfactant loading of up to 2.55 mg/m2·d. However, reactor no. 2 of the system was aerobic and the dissolved oxygen was higher than 3.00 mg/L. The study showed that this type of packed cage RBC system could be applied for treating the cosmetic industry wastewater with surfactant loading of up to 2.55 mg/m2·d under an HRT of 8 h.
Role of Nozzles with Air Holes in Air Entrainment by a Water Jet
Authors: Emiroglu M. Emin , Baylar Ahmet 
Published: May 2018

Abstract
When a water jet impinges a pool of water at rest, air bubbles may be entrained and carried a distance below the pool's surface. This process is called plunging water jet entrainment and aeration. This paper describes an experimental study of the air entrainment rate of circular nozzles with and without air holes, and in particular, the effect of varying numbers and positions of air holes and distance between the location of the air holes and nozzle exit. A negative pressure occurred due to the air holes on the circular nozzles. This phenomenon affected air entrainment. The differences in air entrainment rate were related to changes in the jet shape. It was demonstrated that the air entrainment rates of the circular nozzles with air holes were significantly higher than those of circular nozzles without air holes.
A Review of Water Reuse and Recycling, with Reference to Canadian Practice and Potential: 2. Applications
Authors: Exall Kirsten 
Published: May 2018

Abstract
Common water reuse applications include agricultural and landscape irrigation with treated municipal wastewater, industrial recirculation of process waters, rainwater collection, and groundwater recharge for non-potable and indirect potable reuse. As compared to other countries worldwide, water reuse is currently practised infrequently in Canada, with the focus of most of the water reuse effort within Canada on agricultural irrigation applications. Landscape irrigation and other non-potable urban uses are practised to some extent, but provide an opportunity for expanded application of reclaimed water. Similarly, while water recycling is practised to various degrees within specific industrial sectors, further industrial water reuse and recycling affords an opportunity to conserve large volumes of water. The Canada Mortgage and Housing Corporation (CMHC) has supported a great deal of research into treatment and reuse of domestic greywater for non-potable uses within individual buildings, as well as some work on rainwater collection and use. Groundwater recharge and potable reuse are practised to some extent in extremely dry regions of the world, but public health concerns with respect to emerging trace contaminants may limit the spread of these reuse applications. The main issues associated with each of the above applications are reviewed, and the state of Canadian water reuse and recycling is described.
Determination of 3,3'-Dichlorobenzidine in Industrial Wastewaters
Authors: Lee Hing-Biu , Peart Thomas E. , Terry Ken , Maguire James 
Published: May 2018

Abstract
A solid-phase extraction, chemical derivatization, and gas chromatography/mass spectrometry (GC/MS) method has been developed for the determination of trace 3,3'-dichlorobenzidine (DCB) in industrial wastewater samples. Instead of an octadecylsilane (ODS) cartridge, a Porapak RDX cartridge was used since the latter could be optimized for the extraction of DCB. After the pre-concentration, interfering coextractives in the sample were selectively removed from the cartridge by elution with a 1:1 mixture of acetonitrile and water. DCB was then eluted with acetonitrile and derivatized with pentafluoropropionic acid anhydride. The product was subsequently analyzed by GC/MS in either the electron impact or negative ion chemical ionization mode. Recoveries of DCB and the surrogate, DCB-d6, were better than 90% at spiking levels of 10, 1, and 0.1 µg/L. Based on a concentration factor of 100, the detection limits for DCB in wastewater samples were determined to be 0.1 µg/L by electron impact GC/MS detection, and 0.01 µg/L by negative ion chemical ionization GC/MS detection, respectively. This method has been successfully applied to wastewater samples collected in the Toronto area.
Aquifer Geometry and Hydrochemical Framework of the Shallow Alluvial Aquifers in the Western Part of the Yamuna River Basin, India
Authors: Zaheeruddin  , Khurshid Shadab 
Published: May 2018

Abstract
The Yamuna basin constitutes a part of the Ganga plain which is one of the most densely populated regions and one of the largest groundwater repositories on the earth. Agricultural activities, population growth, rapid industrialization, and unplanned urbanization in the plain have resulted in various geo-environmental hazards, in particular, deterioration of groundwater quality. This studies the aquifer geometry and geochemical evaluation of groundwater in terms of its suitability for domestic and agricultural uses. Groundwater in the basin occurs in Quaternary alluvium and fractures in highly consolidated Alwar quartzites. Hydrogeological cross sections revealed a two- to three-tier aquifer system down to 100 m below ground level. The aquifer sequence comprises of clay, silt, different grades of sand and gravel in varying proportions. Climatic conditions, weathering and anthropogenic activities control the groundwater chemistry in the basin. The pH and electrical conductivity (EC) of the groundwater is variable (pH = 5.5–8.8; EC = 500–6700 µS/cm). At most places, the groundwater is alkaline, hard, and saline. In general, the groundwater has a composition expressed in equivalent units of Na+&gt;Ca2+&gt;K+&gt;Mg2+ for cations and Cl-&gt;SO42-&gt;HCO3-&gt;CO32- for anions. The majority of the samples analyzed are classified as Na-Cl water which imparts residual sodium carbonate (RSC) hazards in irrigation use. The next dominant water types are Ca-Mg-Cl and Ca-Mg-HCO3-. Groundwater with a higher proportion of NO3-, Na+, F-, and K+ at a few sites represents the influence of anthropogenic sources on groundwater composition. An excess of alkali metals (Na+ + K+) over Cl- reflects input from the weathering of sodium- and potassium-rich minerals. The high %Na, EC and sodium adsorption ratio (SAR) values at a few sites restrict its suitability for irrigation.
Interaction of Ozone with Formic Acid: A System which Supresses the Scavenging Effect of HCO3-/CO32-
Authors: Yapsaklı Kozet , Can Zehra S. 
Published: May 2018

Abstract
Formic acid, mainly found in its ionized form at pH values greater than 3.75, is among the major by-products of drinking water ozonation. This study focusses on ozone decomposition reactions when formate ion is present. A mechanistic model was developed for ozone decomposition in the presence of formate ion and alkalinity. n-chlorobutane (BuCl) was used as a hydroxyl radical probe. The proposed mechanism is a combination of all the reactions provided in the literature for ozone decomposition, ozone-formate ion interactions, and formate ion and certain inorganic radical interactions in aqueous solutions. The validity of the proposed mechanism was tested by comparing the experimental data collected at different initial ozone and formate ion concentrations, pH and alkalinity to the model predictions. The model was capable of predicting the ozone decomposition and BuCl oxidation data extremely well when 1.53 M-1s-1 (knew) was used as the reaction rate constant for the reaction between ozone and formate ion, as opposed to the value provided in the literature (100 M-1s-1). Furthermore, according to the proposed model formate ion suppresses the scavenging effect of HCO3- and CO32- ions because the reaction of formate ion with CO3*- radical regenerates the OH* radical that is scavenged by the HCO3- and CO32- ions. This was tested by observing ozone decomposition at different levels of alkalinity in the presence of formate ion. The experimental data did not present any significant effect of alkalinity on the decomposition rate. In addition, the model provided highly reliable predictions of the experimental data collected in the presence of alkalinity when knew was used.
Changes in Immunological Parameters and Disease Resistance in Juvenile Coho Salmon (Oncorhynchus kisutch) in Response to Dehydroabietic Acid Exposure under Varying Thermal Conditions
Authors: Tierney Keith B. , Stockner Eric , Kennedy Christopher J. 
Published: May 2018

Abstract
This study explored the effects of a sublethal 96-h dehydroabietic acid (DHAA) exposure on aspects of the immune system of juvenile coho salmon under varying temperature conditions. Coho were exposed to DHAA concentrations below the determined LC50 value of 0.94 mg/L (95% confidence limits of 0.81 to 1.24 mg/L) for 96 h at either their acclimation temperature (8 or 18°C), or during an acute warm-shock (8 to 18°C) or cold-shock (18 to 8°C). Acclimation temperature alone significantly affected hematocrit (Hct), neutrophil respiratory burst activity (RBA) and leucocyte proportions. With temperature-shock, leucocrit (Lct), RBA and leucocyte proportions were altered. All parameters were affected by DHAA exposure, but not always in a dose-dependent manner. Across groups, DHAA caused Hct, lysozyme, thrombocyte, neutrophil and monocyte proportions to increase, and Lct, RBA and lymphocyte proportions to decrease. DHAA-temperature interactions resulted in the exacerbation of DHAA-induced effects. Exposure temperature had the most significant effect on the susceptibility of coho to Aeromonas salmonicida; fish were more susceptible at cold temperatures and when subjected to a temperature-shock compared to their respective controls. DHAA exposure modulated the response of temperature-shocked fish to this pathogen.
Cadmium Biosorption by S. fluitans: Treatment, Resilience and Uptake Relative to Other Sargassum spp. and Brown Algae
Authors: Davis Thomas A. , Ali Fadi El Cheikh , Giannitti Elisa , Volesky Bohumil , Mucci Alfonso 
Published: May 2018

Abstract
Species of the brown algae Sargassum have been targeted for use in the implementation of strategies to remediate toxic heavy metal contamination in effluents and drinking waters. This work focusses on some of the intrinsic physico-chemical properties of the algal material and aspects of the sorption mechanism, in particular: their maximal metal uptake, the influence of particle size and their resilience to leaching during equilibrium batch experiments. In addition to S. fluitans, the database on cadmium uptake capacities by Sargassum is extended to include S. thunbergii and S. oligocystum, and these are compared to those of two common brown algae. Results of our experiments demonstrate that cadmium sorption is independent of the range of particle sizes investigated (&lt;2 and 3–6 mm), thereby indicating that sorption is not a function of the specific surface area of the biomass exposed to the solution. Dissolved organic carbon (DOC) analyses reveal that leaching to the cadmium solutions during the metal sorption reaction is independent of the biomass preparations used to obtain the two size fractions but decreases with increasing final cadmium concentration.
Determination of System Losses of Geosmin and MIB in Bench-Scale Filtration Apparatus
Authors: Elhadi Sarah L.N. , Huck Peter M. , Slawson Robin M. 
Published: May 2018

Abstract
Geosmin and 2-methylisoborneol (MIB) are two of the causative compounds responsible for the earthy/musty odour problem in drinking water. They are a major concern for the water treatment industry because they are difficult to remove by conventional water treatment practices and are fairly resistant to chemical oxidation. Various studies have been conducted at both bench and full scale to examine the removal of these compounds by adsorption and/or biological filtration. Lack of study at realistic odour compound concentrations and disregard for losses of these compounds by other means (i.e., volatilization or adsorption) represent some of the limitations of such studies. The bench-scale investigation reported herein focussed on system design and minimization of system losses. The results indicated that the preferred system design included the use of Teflon feed bottles, Teflon tubing, and a glass filter column in which the influent feed line descended close to the media surface. Such a design minimized system losses of both geosmin and MIB to 42 and 30%, respectively, based on target influent concentrations of 200 ng/L.
Effect of Aeration on Fresh and Aged Municipal Solid Waste in a Simulated Landfill Bioreactor
Authors: Warith Mostafa A. , Takata Graham J. 
Published: May 2018

Abstract
Municipal solid waste (MSW) is slow to stabilize under conventional anaerobic landfill conditions, demanding long-term monitoring and pollution control. Provision of aerobic conditions offers several advantages including accelerated leachate stabilization, increased landfill airspace recovery and a reduction in greenhouse gas emissions.
Air injection was applied over 130 days to bench-scale bioreactors containing fresh and aged MSW representative of newly constructed and pre-existing landfill conditions. In the fresh MSW simulation bioreactors, aeration reduced the average time to stabilization of leachate pH by 46 days, TSS by 42 days, TDS by 84 days, BOD5 by 46 days and COD by 32 days. In addition, final leachate concentrations were consistently lower in aerated test cells. There was no indication of a gradual decrease in the concentration of ammonia, and it is likely this high ammonia concentration would continue to be problematic in bioreactor landfill applications.
This study focussed only on biodegradability of organics in the solid waste. The concentrations of the nonreactive or conservative substances such as chloride and/or heavy metals remain in the bioreactor landfills due to the continuous recirculation of leachate.
The results of this study demonstrate the potential for air injection to accelerate stabilization of municipal solid waste, with greatest influence on fresh waste with a high biodegradable organic fraction.
Simulation of Oxygen Transfer Rates in Circular Aeration Tanks
Authors: Rao Achanta Ramakrishna , Laxmi B.V. Bharathi , Narasiah K. Subba 
Published: May 2018

Abstract
Experiments were conducted to study the performance of circular and square tank surface aerators on the oxygen transfer coefficient and to a limited extent on power requirements. All the tanks are geometrically similar except for their shapes. They consist of a rotor of diameter, D, fixed with six flat blades rotating with a speed, N, in pure waters of viscosity, υ, at room temperature. A simulation equation to predict the oxygen transfer coefficient, k = KLa20(υ/g2)1/3 for any given dynamic parameter governing the theoretical power per unit volume, X = N3D2/(g4/3υ1/3) was developed for circular tank aerators. The data on square tank aerators support another such simulation equation developed earlier for square tanks. A comparison of results, while re-aerating the same volume of water in both the shapes of tanks, leads to the interesting conclusion that for a given rotor speed the oxygen transfer rate is substantially more in square tanks than in circular tanks; whereas for a given effective input power to the rotor the oxygen transfer rate is more in circular tanks than in square tanks. This suggests that square tanks are preferred to circular tanks to raise the oxygen concentrations at a faster rate, whereas the circular tanks are advantageous as far as power requirements are concerned.
Radiation-Induced Degradation and the Effect of Scavengers on Benzene, Monochlorobenzene and 1,2-Dichlorobenzene in Aqueous Solutions
Authors: Takriti Salaheddin 
Published: May 2018

Abstract
The degradation of benzene, monochlorobenzene and 1,2-dichlorobenzene in aqueous solution by gamma irradiation was investigated. The effect of the irradiated solution composition was studied. The results showed that benzene is more resistant to destruction than chlorinated benzenes. The presence of oxidizing and reducing reactive species and the rapid reaction rates with halogenated benzenes increased the degradation rate of the pollutants. Dechlorination of CB and 1,2-DCB was observed. High performance liquid chromatography (HPLC) and spectroscopy (UV-Vis) were used to monitor changes in the radiation solutions. The final aqueous irradiation products were shown to be a complex mixture of by-products. The addition of scavengers such as methanol and ethanol required larger doses to decompose the pollutants when compared to those solutions with no additives.
Wet-Weather Flow Management in the Great Lakes Areas of Concern
Authors: Kok Sandra 
Published: May 2018

Abstract
Under the Government of Canada's Great Lakes Program, the Great Lakes Sustainability Fund and its predecessor programs (the Great Lakes Cleanup Fund and the Great Lakes 2000 Cleanup Fund) were established to implement cleanup actions and strategies that would contribute to the restoration of beneficial uses in environmentally degraded areas (known as Areas of Concern) in the Great Lakes basin. The Great Lakes Sustainability Fund is administered by Environment Canada on behalf of eight Government of Canada departments. Contributing to impaired beneficial uses are municipal wastewaters generated from the urban centres in the Great Lakes Areas of Concern. These municipal wastewaters include treated sewage and wetweather discharges of combined sewer overflows and stormwater runoff. This paper provides an overview of the Municipal Wastewater Program of the federal government's Great Lakes Sustainability Fund and highlights the progress made to date under the program towards wet-weather flow management and the Program's role in developing and demonstrating sustainable approaches and technologies in the Great Lakes Areas of Concern.
The Role of Water Balance Modelling in the Transition to Low Impact Development
Authors: Graham Patrick , Maclean Laura , Medina Dan , Patwardhan Avinash , Vasarhelyi Gabor 
Published: May 2018

Abstract
Low impact development (LID) is increasingly being viewed by local governments and developers alike as a viable approach to stormwater management that can effectively protect aquatic habitat and water quality. LID relies on distributed runoff management measures that seek to control stormwater volume at the source by reducing imperviousness and retaining, infiltrating and reusing rainwater at the development site.
Early conventional stormwater management practices tended to focus on stormwater quantity and controlling a few extreme rainfall events, whereas the more frequent storms, which represent the majority of total runoff volume, carry most of the pollutants, and control the geomorphology of streams, were addressed in stormwater quality design practiced during the last decade. These frequent events are most effectively managed with a volume control approach, often described as stormwater source control or Low impact development (LID). Such an approach is described in this paper, demonstrating how water balance modelling can be an effective tool for evaluating and supporting implementation of LID options such as bioretention, pervious paving, numerous types of infiltration systems, rainwater reuse and green roofs. It also discusses recently developed water balance modelling software, including an Internet-based planning tool and a design optimization tool.
Accumulation of Trace Metals in Freshwater Invertebrates in Stormwater Management Facilities
Authors: Anderson Bruce C. , Bell Tracy , Hodson Peter , Marsalek Jiri , Watt W. Edgar 
Published: May 2018

Abstract
Availability and uptake of metals in the accumulated sediments in stormwater treatment facilities was assessed by the metal accumulation patterns observed in freshwater mussels, as the first step in an Environmental Risk Assessment (ERA). Freshwater mussels, Elliptio complanata, were caged in various locations in several stormwater treatment facilities and control sites in southeastern Ontario. Mussels were sampled at 2, 5.5, 8, 11 and 14 weeks, and Ni, Cr, Cu, Cd and Pb concentrations in soft tissues were determined by ICP-MS. Selection of these metals was based on previous studies which had identified them in substantial quantities in stormwater pond sediments. A significant decrease in Ni concentrations and an increase in Pb concentrations relative to background levels were observed. Concentrations of Cu, Cd and Cr were generally not significantly different from background.
Total metal concentrations in sediments were also determined, and compared with the observed mussel metal concentrations. No correlations were observed between total metals in sediment and the accumulated burden in the mussels. The results suggest that Pb is a possible concern in these stormwater facilities due to its availability. Ni, Cr and Cd did not appear to be in bioavailable forms and Cu had limited availability. The study was complementary to other work examining trace metals in stormwater management facilities, and provides further useful information about the habitat quality of these facilities, and the ecotoxicological risks that might be posed to resident species.