bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impacts of Municipal Wastewater Effluents on Canadian Waters: a Review
Authors: Chambers P.A. , Allard M. , Walker S.L. , Marsalek J. , Lawrence J. , Servos M. , Busnarda J. , Munger K.S. , Adare K. , Jefferson C. , Kent R.A. , Wong M.P. 
Published: March 2019

Abstract
Domestic sewage is a major threat to receiving waters throughout the world. In Canada, a high proportion of the population (81%) is served by municipal wastewater treatment facilities. Nevertheless, discharges from wastewater treatment plants, stormwater sewers and combined sewers have caused adverse impacts on some lakes, rivers and coastal waters. The most publicly recognized impacts are shellfish harvesting restrictions and beach closures resulting from microbial contamination. Habitat degradation and contamination also occur and these, in turn, have altered the abundance and diversity of aquatic organisms. Our findings on the effects of municipal wastewater discharge suggest that there is a need to review sewage treatment requirements in Canada. Further research is also required on the interactive and cumulative responses to habitat degradation and to long-term exposure to persistent and bioaccumula-tive pollutants. Finally, an integrated approach to wastewater management is needed that addresses loadings from treatment plants, stormwater sewers, combined sewer overflows and other wastewater sources.
Réduction de la demande en chlore et des précurseurs de sous-produits de désinfection par une ozonation suivie d'une biodégradation : effets de la reminéralisation
Authors: Zoungrana Charles J. , Desjardins Raymond , Prevost Michele 
Published: March 2019

Abstract
Des essais ont été faits afin de montrer les effets d'une reminéralisation sur les performances d'un traitement biologique. La demande en chlore ainsi que les potentiels de formation des trihalométhanes, des acides haloacétiques, des haloacétonitriles, des haloacétones et de la chloropicrine ont été suivis. Une augmentation de l'alcalinité des eaux permet un meilleur enlèvement des paramètres étudiés tant par l'ozonation que par la biodégradation. Par exemple, l'abattement des précurseurs de trihalométhanes, des haloacétonitriles et des acides acétiques est respectivement de 21, 50 et 28% dans les eaux non reminéralisées (alcalinité de 25 mg/L CaCO3). Dans les eaux reminéralisées à 250 mg/L CaCO3 ces abattements sont plus importants soit : 30, 68 et 50%. Un effet similaire est observé pour la biodégradation. Ainsi dans les eaux non reminéralisées les enlèvements sont de 54, 77 et 69%, alors qu’ils sont de 67, 86 et 80% dans les eaux reminéralisées.
Characterization of Treated Effluent from a Chemithermomechanical Pulping Process Using Macroporous Resins
Authors: Agbekodo K.M. , Huck P.M. , Andrews S.A. , Peldszus S. 
Published: March 2019

Abstract
This study developed a characterization of the organic matter remaining in a chemithermomechanical pulping (CTMP) effluent after biological treatment and evaluated the potential impact of this effluent when discharged into the receiving environment. The methodology employed involved fractionation with macroporous resins to allow for the isolation of hydrophobic and hydro-philic organic materials. The study also examined the treated effluent’s reactivity with chlorine, a typical drinking water disinfectant, in order to assess the formation potential of chlorinated by-products and the chlorine demand in a downstream drinking water treatment plant. Results showed that the dissolved organic carbon (DOC) in a treated effluent from a CTMP mill consisted of 87% hydrophobic material (primarily humic substances), 5% hydrophilic acids and 3 to 4% nitrogenous compounds. At least 95% of the DOC was isolated using three different macroporous resins. The chlorine demand of the biotreated CTMP effluent was two to three times higher than is typical for natural organic matter from surface water. This indicated that the organic material in the CTMP effluent was highly reactive with chlorine and will likely be reactive with other oxidants such as ozone, which is also applied in the drinking water industry. Moreover, the disinfection by-products chloroform and trichloroacetic acid were formed in high concentrations as a result of chlorination. The biotreated CTMP effluent had a high chemical oxygen demand (at least 1,100 mg/L) but a relatively low biochemical oxygen demand (less than 100 mg/L), which was to be expected after biological treatment. Hence, discharge of these effluents could release high concentrations of non- or slowly biodegradable organic matter into the downstream aquatic environment. Water pollution control policies should therefore consider the potential impact of treated effluents from CTMP mills with regard to their high DOC and the potential for chlorinated by-product formation upon drinking water disinfection.
Heavy Metals and PAHs in Stormwater Runoff from the Skyway Bridge, Burlington, Ontario
Authors: Marsalek J. , Brownlee B. , Mayer T. , Lawal S. , Larkin G.A. 
Published: March 2019

Abstract
Samples of stormwater runoff from the Skyway Bridge in Burlington, Ontario, were analyzed for five heavy metals (Zn, Pb, Ni, Cu and Cd) and 14 polycyclic aromatic hydrocarbons (PAHs) in dissolved and particulate-bound phases. Among the metals studied, the highest mean event-mean concentrations in whole-water samples were found for Zn, Cu and Pb (0.337, 0.136 and 0.072 mg L-1). These data compared well with those in the literature. Pb concentrations had to be compared to the most recent data reflecting the use of unleaded gasoline. Zn, Ni and Cu in the dissolved phase accounted for 35 to 45% of concentrations in whole-water samples. Mean PAH event-mean concentrations in whole-water samples ranged from 0.015 to 0.5 µg L-1 for individual compounds. Dissolved phase PAHs represented less than 11% of whole-water concentrations. Mean concentrations of Zn, Cu and Pb (997, 314 and 402 µg g-1) in runoff sediment were rather high and indicated that this sediment was “grossly polluted” according to the (Ontario) Ministry of Environment and Energy guidelines for sediment quality. Metal concentrations in the
An Integrated Acid Rain Assessment Model for Canada: from Source Emission to Ecological Impact
Authors: Lam D.C.L. , Puckett K.J. , Wong I. , Moran M.D. , Fenech G. , Jeffries D.S. , Olson M.P. , Whelpdale D.M. , McNicol D. , Mariam Y.K.G. , Minns C.K. 
Published: March 2019

Abstract
Integration of data and component models describing acidifying emissions, atmospheric transport, water and soil quality, fisheries, wildlife and socio-economics forms part of a decision-support system development for examining management options for acid rain issues in Canada post-year 2000. The emphasis is on scale consistency, optimization solutions, scenario testing and uncertainty propagation. The integrated model was evaluated with recent data and model consistency cross-checked with optimized and scenario testing results for Eastern Canada. Examples of predicted results on water quality and ecological impact were presented as part of an assessment for the evaluation of control options for acidifying emissions.
Acute Toxicity Testing with Juvenile White Sturgeon (Acipenser transmontanus)
Authors: Bennett W.R. , Farrell A.P. 
Published: March 2019

Abstract
The primary goal of this study was to investigate the possibility of using early life stages of white sturgeon (Acipenser transmontanus) (eggs, larvae and fry) as a species relevant to the Fraser River, B.C., for the acute and sublethal toxico-logical testing of forest industry effluents. Here we report the first successful acute toxicity tests for 8-day-old larvae and 42-day-old fry exposed to several chemicals known to be released into the Fraser River (i.e., 6 monochlorovanillin [6 MVAN], 4,5 dichloroguaiacol [4,5 DCG], 4,5 dichlorocatechol [4,5 DCAT], pentachlorophenol [PCP], and didecyldimethylammonium chloride [DDAC]). In most cases, white sturgeon fry were at the lower end of the range for acute toxicity values for chlorinated phenolic compounds, when compared with other juvenile fish species, and they were extremely sensitive to DDAC. The larval stage was usually more sensitive than the fry stage. Acute toxicity tests with fertilized eggs were unsuccessful. A postexposure growth study was inconclusive because neither control nor toxicant-exposed larvae and fry withstood the additional handling used for measuring body mass. At 62-days-old, fry were more tolerant of handling. This allowed measurement of their swimming performance. Although we have concerns about the reliability of using larvae for acute toxicity testing at this time, 60-day-old white sturgeon fry would appear to be both a sensitive and relevant species for assessing environmental impacts relevant to the Fraser River.
A Micro-Algal Solid-Phase Test To Assess the Toxic Potential of Freshwater Sediments
Authors: Blaise Christian , Menard Lucie 
Published: March 2019

Abstract
To assess the degree of toxicity of freshwater sediments which may arise from both readily available and ad(ab)sorbed contaminants, we have developed a novel "direct contact" solid-phase assay with the widely used Chlorophyte Selenastrum capricornutum. With this procedure, algal cells were exposed for 4 or 24 h to serial dilutions of test sediments. The capacity of exposed cell esteras-es to cleave the non-polar stain fluorescein diacetate and liberate fluorescein, a polar and fluorescent by-product, then becomes a criterion to determine the extent to which the algae have been intoxicated by the sediment. Individual cell fluorescence (from fluorescein) is rapidly and precisely quantified with the help of flow cytometry to determine a toxicity endpoint which relates to both esterase inhibition and cell membrane integrity. The algal solid-phase assay (ASPA) was appraised with certified reference material sediments prepared by the National Water Research Institute in Burlington as well as with some naturally contaminated sediments originating from various locations in the Québec portion of the Saint-Lawrence River. ASPA toxicity responses (IC50s) generated for sediments span over more than two orders of magnitude, indicating its apparent discriminatory power to demarcate their toxic potential on the basis of their contamination level. Correlation analysis, conducted with selected certified reference material sediments, suggests that ASPA responses may be partly linked to PAH and total PCB hold content. While further validation studies are planned for ASPA, it appears to promise as a useful phytotoxicity screening tool to assess the toxic potential of freshwater sediments.
Influence of Data Preprocessing and Kernel Selection on Probabilistic Neural Network Modeling of the Acute Toxicity of Chemicals to the Fathead Minnow and Vibrio fischeri Bacteria
Authors: Niculescu Stefan P. , Kaiser Klaus L.E. , Schüürmann Gerritt 
Published: March 2019

Abstract
We investigated the connection between the data preprocessing strategy and kernel choice on the quality of the associated basic probabilistic neural network models for the acute toxicity of various chemicals to the fathead minnow and to Vibrio fischeri bacteria. The models employ exclusively structural parameters and physicochemical properties as inputs. Results show that the Gaussian kernel is preferable over the reciprocal kernel model. Data preprocessing based on the hyperbolic tangent and the sigmoid logistic transforms provides the best results at the level of the cross validation experiment. Improved models based on cross validation partial models and linear corrections were also investigated. The results show that the improved models with data preprocessing based on the hyperbolic tangent and the finite interval transforms are the best with practically identical quality of predictions.
Nonspecific Chlorination of Organics: a Chemistry Unique to Human Industry? (Putting Kraft Mill AOX Emissions into Perspective)
Authors: Archibald Frederick , Valeanu Loredana , Leichtle Gunther , Guilbault Benoit 
Published: March 2019

Abstract
To counter the claim that all biotreated organochlorine (AOX) emissions from modern kraft mills are unnatural and inherently hazardous, it has been argued that over 2400 different AOX compounds are now known to be produced by living organisms. This is an invalid rationale. These 2400 natural compounds are mostly specific halometabolites — each is produced as a large number of identical molecules by a specific enzyme-mediated mechanism. In contrast, in a kraft mill bleachery, heterogeneous wood derivatives are non-specifically chlorinated by hypochlorous acid (HOCl) or hypochlorite ion (OCl-) to produce mixtures containing hundreds of different AOX species. It is therefore much more reasonable to compare mill-derived AOX to other human and natural sources of OCl-/HOCl-generated non-specific AOX.
Chloroperoxidase (CPO)-type enzymes naturally produce HOCl and OCl-from common chloride ions and hydrogen peroxide (H2O2). They have now been demonstrated in bacteria, fungi, algae, lichens, higher plants and animals. We demonstrate that a common fungal CPO can, when applied to soil extracts, lignins, cellulosics, tannins and natural lake water organics, rapidly generate nonspecific AOX.
In agreement with earlier work done in other geographic areas, AOX was found in all of a wide range of samples from the Montreal region, both from urban and relatively remote pristine lakes and woodlands. Much of it is almost certainly produced via nonspecific HOCl/OCl- chlorination.
Finally, we demonstrate that nonspecific AOX is produced by a CPO in mammalian blood as the natural result of the body's immune system fighting infections. Thus, HOCl/OCl- based production of AOX from mixtures of organic molecules is seen to be a common occurrence in nature as well as a product of human technology.
Aluminum Speciation during Drinking Water Treatment
Authors: Srinivasan P.T. , Viraraghavan T. , Kardash B. , Bergman Joe 
Published: March 2019

Abstract
Aluminum is one of the trace inorganic metals present in drinking water. Aluminum present in alum (a widely used coagulant for water treatment) as well as naturally occurring aluminum in raw water is transformed into various forms (speciation) during drinking water treatment. Speciation of aluminum during drinking water treatment is essential to understand the behavior of aluminum and aluminum species removal during water treatment and also to identify the factors influencing residual aluminum in treated waters. In this connection, an aluminum speciation study was conducted at the Buffalo Pound water treatment plant. Aluminum was fractionated into eight different forms (total, soluble + colloidal, soluble, organic, inorganic, particulate, suspended, and colloidal aluminum). Speciation results showed that raw lake water total aluminum concentrations were highly variable, and almost all of the raw water particulate aluminum (predominant species of total aluminum) was present in suspended form. Soluble aluminum levels throughout the plant (raw to treated) were less than 50 µg/L and most of the soluble aluminum was in organic form. The study showed that granular activated carbon was capable of removing soluble aluminum in organic form. Residual aluminum present in treated water consisted of mostly particulate and organic forms of aluminum. Raw water particulate aluminum correlates well (R2 = 0.90) with raw water turbidity, implying that removal of turbidity from raw water will reduce particulate aluminum in treated waters. Similarly the organic fraction of residual aluminum was influenced by the high dissolved organic carbon present in the raw water. As the soluble aluminum concentrations were less than 50 µg/L, the plant would not have any difficulty to meet a guideline value for aluminum in treated waters in the range of 0.1 to 0.2 mg/L as dissolved aluminum.
Factors Affecting Oxygen Transfer in Lab-Scale Activated Sludge Reactors Treating Bleached Kraft Mill Effluent
Authors: Hui K.W. Leo , Duff Sheldon J.B. 
Published: March 2019

Abstract
In aerobic biological wastewater treatment processes, oxygen must be transferred from the gas phase to the liquid phase to support oxidation of dissolved organics and endogenous metabolism by the bacteria. Power required to supply this oxygen in suspended growth systems can represent a significant fraction of the operating costs of such processes. In this study, the interfacial mass transfer coefficient KLa for water was found to be reduced by up to 28% (average 13%) by the addition of antifoaming agent. KLa values were reduced by up to 43% (average 26%) by the dissolved organics in primary treated bleached kraft mill effluent. There was no significant difference between the KLa for water and biologically treated bleached kraft mill effluent.
Volatile Fatty Acids Production by Anaerobic Whey Permeate Biodegradation in a Continuous Bioreactor
Authors: Imbeault Nathalie , Paquet Marcel , Côté Raynald 
Published: March 2019

Abstract
This paper addresses the production of volatile fatty acids with fermentation of whey permeate under acidogenic conditions. The coal-immobilized biomass of an anaerobic fluidized bed reactor operated with a fairly constant hydraulic residence time of 12 min transformed the substrate (whey permeate i.e., essentially lactose) into a blend of acetic, propionic, butyric and isobutyric acids corresponding to between 2 and 19, 1 and 6, 11 and 30, 0 and 2% of the initial load (carbon basis), respectively. There was a slight decrease in the sugar transformation efficiency (65 to 48%) with the increase of the organic loading rate (OLR) which varied from 586 to 3339 g sugar/Lreactord. At the highest OLR of 3339 g sugar/Lreactor.d, the biomass transformed 19% of the substrate into a blend of acetic, propionic, butyric and isobutyric acids. Residual sugar and bio-gas were 52 and 2%, respectively, of the initial load (carbon basis).
Cet article fait référence L une étude sur la production d’acides gras volatiles par fermentation anaérobie du perméat de lactosérum dans un bioréacteur. La biomasse fixée aux grains de charbon composant le lit fluidisé, opérant avec un temps de rétention hydraulique de 12 minutes, transformait le substrat (perméat i.e., essentiellement lactose) en un mélange d’acide acétique, propionique, n-butyrique et isobutyrique correspondant respectivement L 2 et 19, 1 et 6, 11 et 30, 0 et 2% de la charge initiale (sur la base d’un bilan de carbone). Il a été possible d’observer une légère diminution de l’efficacité de la biodégradation du sucre (65 L 48%) avec une augmentation du taux de charge organique lequel variait de 586 L 3 339 g de sucre/Lréacteurd. L la charge organique la plus forte, soit 3 339 g de sucre/Lréacteur.d, la biomasse transformait le substrat L 19% en un mélange d’acide acétique, propionique, n-butyrique et isobutyrique. La part du sucre résiduel était de 52% et celle du biogaz L 2% (bilan de carbone).
Review of the Aquatic Toxicity, Estrogenic Responses and Bioaccumulation of Alkylphenols and Alkylphenol Polyethoxylates
Authors: Servos Mark R. 
Published: March 2019

Abstract
A review of the available information on the toxicity and bioaccumulation of alkyphenols (AP) and their polyethoxylates (APE) and polyethoxycarboxylates (APEC) was conducted in support of their assessment as Priority Substances under the Canadian Environmental Protection Act. This included an examination of the acute and chronic toxicity of these compounds in a wide variety of aquatic organisms as well as an examination of their potential effects on endocrine function in fish and aquatic invertebrates. Although the data in the literature are scattered among many species, different test methods and chemicals, there is a consistent pattern in the toxicity. Nonylphenol (NP) and octylphenol (OP) are both acutely toxic to fish (17-3000 µg/L), invertebrates (20-3000 µg/L) and algae (27-2500 µg/L). In chronic toxicity tests no observable effect concentrations (NOEC) are as low as 6 mg/L in fish and 3.7 µg/L in invertebrates. There is an increase in the toxicity of both NPEs and OPEs with decreasing EO chain length. NPECs and OPECs are less toxic than corresponding APEs and have acute toxicities similar to APEs with 6-9 EO units. APs and APEs bind to the estrogen receptor resulting in the expression of several responses both in vitro and in vivo, including the induction of vitellogenin. The threshold for vitellogenin induction in fish is 10 µg/L for NP and 3 µg/L for OF. APEs also affect the growth of testes, alter normal steroid metabolism, disrupt smoltificaton and cause intersex (ova-testes) in fish. The available literature suggests that the ability of AP and APEs to bioaccumulate in aquatic biota in the environment is low to moderate, BCFs and BAFs in biota, including algae, plant, invertebrates and fish range from 0.9 to 3400. Although there are relatively few data available for OP or OPEs, their potential to bioaccumulate is expected to be similar to that of corresponding NP and NPEs.
Short Communication: A Note of Caution to Users of ECOSAR
Authors: Kaiser Klaus L.E. , Dearden John C. , Klein Werner , Schultz T. Wayne 
Published: March 2019

Abstract
ECOSAR (1998), a personal computer software program available from the U.S. Environmental Protection Agency (EPA) and affiliated vendors, is used to estimate the toxicity of chemicals to aquatic organisms, particularly fish, daphnid and algae species. It relies on approximately 150 equations, each for a chemical class of substances (Clements et al. 1996), which are linear correlations (SARs) of measured toxicity values of class-representative compounds with their octanol/water partition coefficients, with the latter taken from a database or computed by a companion program.
Pesticides in the Red River and its Tributaries in Southern Manitoba: 1993—95
Authors: Rawn Dorothea F.K. , Halldorson Thor H.J. , Woychuk Robert N. , Muir Derek C.G. 
Published: March 2019

Abstract
Pesticide concentrations and loadings at three locations along the Red River and on seven of its tributaries in southern Manitoba were determined over a three year period. Samples (18 L) were collected on a biweekly schedule between spring and late autumn in 1994 and 1995 and triweekly throughout the initial year of the study (1993) between June and October. Pesticide recoveries ranged from 14 to 115%, and those with &lt; 80% recovery (bromoxynil, 2,4-D,diclofop, MPCA and triclopyr) were recovery corrected. Maximun concentrations were related to regional use periods, despite greatest runoff occurring during spring melt and early summer rains. Pesticides were not present at elevated levels during this period. The pesticides detected in the highest frequency in the Red River tributaries generally were those used most extensively (e.g., MCPA). MCPA concentaraions for all sites ranged from &lt; 0.01 to990 ng/L. MCPA had the largest loadings of all herbicides in each tributary, although loads were low (9-3100 g) compared to usage. Atrazine and alachlor were frequently detected in the Red River. Atrazine is widely used in the neighbouring U.S. states, and loadings of this chemical in the Red River were similar to loadings of the highly used and less persistant phenoxyacids, although it was used only to a minor extent in Manitoba. Alachor, althiugh not in used in Canada, was present (&lt;0.060-150 ng/L) in the Red River at each sampling site, which reflected U.S. usage of this product. Urban usage of chlorpyrifos, 2,4 D and MCLA contributed to loadings along the Red River. Pesticide concentrations generally were well below Canadian water quality guidelines in the Red River drainage basin; however, chlorpyrifos concentrations occassionally exceeded guideline levels for the production of freshwater aquatic life.