bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toxic Chemical Survey of Municipal Drinking Water Sources in Atlantic Canada 1985-1988
Authors: O’Neill H.J. , Pollock T.L. , Brun C.L. , Doull J.A. , Léger D.A. , Bailey H.S. 
Published: March 2019

Abstract
During the period of 1985 to 1988, municipal water supply sources in Atlantic Canada were sampled and analyzed for various compounds including major ions, nutrients, heavy metals, pesticides and synthetic organic chemicals. Both surface and ground water sources were sampled. Ninety-eight percent of supply sources were within the health-related maximum acceptable concentrations of the Guidelines for Canadian Drinking Water Quality (Health and Welfare Canada 1987), and eighty-five percent within the aesthetic guidelines.
A geographic information system was used to classify the municipal sources by surrounding land-use and comparisons made to nitrate-N. All samples reported as 1.0 mg.L−1 or greater were from ground water supplies in areas classed as high agricultural use. Though a direct input from agriculture was established for two wells, the source of nitrate-N at the remaining sites was attributed to soil-N and/or fertilizer-N.
Uptake of Selected Organochlorine Contaminants in Fishes Resident in the Fraser River Estuary, Vancouver, British Columbia
Authors: Rogers I.H. , Macdonald J.S. , Sadar M. 
Published: March 2019

Abstract
Starry flounders, prickly sculpins and other resident fishes were captured in the Lower Fraser River in the summers of 1987, 1988 and 1989. Control fish were taken from the estuary of the uncontaminated Homathko River on the B.C. coast in 1987 and 1988. The fish were analysed for chlorophenols, chloroguaiacols and PCBs. The residues most commonly detected were PCBs, tetra-and pentachlorophenol. Fish from the Main Arm contained PCBs that resembled Arochlor 1248 whereas those from the North Arm contained PCBs that resembled a mixture of Arochlors 1254 and 1260. Chloroguaiacol uptake was greater in flounders than in other species. Although PCBs appear to have declined markedly in the Lower Fraser from values published in the early 1970s, there is a need to measure the coplanar fraction to understand their toxic significance to the food chain. Tetra- and pentachlorophenol have declined following a change by industry to the use of alternative sapstain prevention treatments.
Planning Irrigation Water Supplies for the Organic Soils of South-Western Quebec
Authors: Barrington S.F. , Madramootoo G. , Beaudoin G. , Millette J. 
Published: March 2019

Abstract
The organic soils of the south-western region of the province of Quebec are an important agricultural resource supporting an annual vegetable production in excess of 115 million dollars. This important soil resource has been extensively exploited for the past 25 years, and is therefore subsiding at an excessive rate, In order to reduce this rate of subsidence, better irrigation practices must be introduced along with wind-breaks and cereal rotation. These improved irrigation practices require the availability of large volumes of water in a region where the topography does not allow for the storage of runoff within deep valleys. Furthermore, the procurement of these irrigation volumes must not jeopardise the water supply required by the urban communities and industries. An analysis of the available water supplies indicates that the best choice is the farm pond.
Polycyclic Aromatic Hydrocarbons in Suspended Particulates from Hamilton Harbour
Authors: Mayer T. , Nagy E. 
Published: March 2019

Abstract
The concentrations and relative abundances of sixteen priority pollutant polycyclic aromatic hydrocarbons (PAHs) were measured in suspended particulates and benthic sediments from Hamilton Harbour. The PAH concentrations in suspended particulates, often as high as PAH concentrations in benthic sediments, ranged between 4.41 and 106.02 µg/g. The highest PAH concentrations were found in areas close to the industrial sites. Selected samples of suspended particulates from western part of Lake Ontario were also analyzed for PAHs to learn about the transport of PAHs from the harbour to Lake Ontario via the Burlington Ship Canal. The results reveal export of PAHs along with the other contaminants from Hamilton Harbour to Lake Ontario.
In addition to PAHs, n-alkanes were determined in all samples, as they are readily determined from the extracts and they are useful in deciphering the sources of suspended particulates, hence particle-associated PAHs.
Effect of Sample Storage Conditions on Body Burden Analysis of Organic Contaminants in Unionid Mussels
Authors: Hanna Micheline 
Published: March 2019

Abstract
In order to quantitatively assess the effect of sample storage conditions on the body burden analysis of organic contaminants, a comparative analysis was carried out on the unionid mussel Elliptic complanata. The mussels were divided into two groups, each with distinct storage conditions, while Group A was kept in the freezer at −20°C, Group B was kept in the refrigerator for five days at 5°C. All the compounds present in the control were also present in Group B samples. Analysis of the organic contaminants in each of these two groups showed that for total PCB concentrations, the two treatments were not significantly different; however when compared individually 6 of the 13 PCB congeners showed significant differences. The observed differences were relatively small for individual PCB congeners (7.1 to 15.3%), higher for chlorobenzenes (10.5 to 36.4%), and yet higher for HCE (44.1%); the difference for HCE, although large is nevertheless not significant, even if only marginally so.
Hydrochemical Modeling of Metal Fate and Transport in Freshwater Environments
Authors: Dzombak David A. , Ali M. Ashraf 
Published: March 2019

Abstract
During the last decade there has been growing interest in the development of hydrochemical models (coupled transport-chemistry-biology models) for better understanding and, eventually, for predicting the fate and transport of metals in freshwater environments. While there has been much discussion of such models and their submodels, and detailed examinations of the mechanistic descriptions and mathematics involved in their formulation, there has been relatively little attention focused on how well they perform in describing field data. This paper provides a look at the state-of-the art in hydrochemical modeling of metal fate and transport in groundwater, riverine and lacustrine systems through review of reported model validation attempts. Focus is on those models that have been applied to describe field data; the degree of success achieved and related factors are examined. Key observations drawn from our review of available hydrochemical models and attempted applications to field data are as follows: (1) most existing models consider steady one-dimensional flow only; (2) most existing models consider only one or a few chemical reaction mechanisms, with sorption-desorption being the most common; (3) local equilibrium is assumed in most models, though kinetic formulations for some chemical processes have been incorporated in some models; and (4) interaction of metals with biota have been considered in only a few models and in a very simplified manner. The most advanced hydrochemical models for metal fate and transport appear to be those for groundwater systems, followed in order by those for rivers and lakes. From a larger perspective, however, hydrochemical models for metals are still at an early stage of development for all freshwater environments.
Metal Ion Immobilization by Bacterial Surfaces in Freshwater Environments
Authors: Schultze-Lam Susanne , Thompson Joel B. , Beveridge Terry J. 
Published: March 2019

Abstract
Bacteria are ubiquitous life forms and occur throughout most natural environments. Consequently, they have developed a full spectrum of metabolic functions to adapt themselves to a diverse range of external milieux. These adaptations have been so successful that, in a global way, they are responsible for the cycling of many important elements (e.g., C, N, S, P, etc.). In this review we concentrate on their surface interaction with soluble metals and their innate ability to concentrate them and form minerals from metal salts within natural waters, sediments and soils. Since most of the readers of this article will not be bacteriologists, we first give a brief overview of the make-up of bacterial surfaces. We also discuss the formation and composition of microbial biofilms which are instrumental in immobilizing toxic metals.
Detection of Metal Toxicity Using Natural Phytoplankton as Test Organisms in the Great Lakes
Authors: Munawari Mohiddin , Legner Milos 
Published: March 2019

Abstract
This paper presents an overview of techniques utilizing natural phytoplankton for the detection of metal-Induced stress in the Great Lakes. Both field and laboratory procedures are designed to evaluate either structural changes or functional response of test organisms. This up-to-date compendium provides a choice of techniques, which permits a holistic assessment of the stress caused by toxic metals. Recently introduced techniques, such as normalized size spectra analysis, flow cytometry, and the evaluation of a continuous-flow system response to metal toxicity, are discussed in more detail to explore their future potential. Owing to their key position in the food web, high turnover rates, abundance, and sensitivity to environmental perturbation, phytoplankton serve as reliable early warning indicators of ecosystem deterioration and its restoration.
Water at the Outlet of the St. Lawrence River Part I - Sampling and Major Cations
Authors: Barbeau C. , Sérodes J.-B. , Paquet M. 
Published: March 2019

Abstract
The St. Lawrence River exports important loads of contaminants to the estuary, but good estimates of annual loadings are presently not available. During two years (1989–91), discrete and composite samples were taken on a daily basis at the water intake of the drinking water treatment plant of Lévis in front of Québec City. Our data indicate that discrete samples are representative of the bulk of the water and that magnesium or calcium measurements provide valuable information on the species transported to the estuary in the dissolved phase. Any decrease in magnesium concentrations at Lévis is the result of relative flow increases from the tributaries of the river. Using high flow episodes in tributaries and daily magnesium measurements at Lévis, the time of transport of the dissolved phase from many sources along the river has been evaluated. At high flow, the time of transport from the Carillon Dam (on the Ottawa River) to Lévis is 11 days, while it is 8 days from Beauharnois. With these data, a predictive model using magnesium (or calcium) as the chemical parameter characterizing the dissolved phase of the St. Lawrence River at the mouth of the estuary was developed. Loadings to the estuary of any dissolved contaminant can now be estimated by combining daily calculated flow values with daily measured water composition at Levis.
St. Clair River Head and Mouth Water Quality Monitoring, 1987–89
Authors: Chan C. H. 
Published: March 2019

Abstract
Water and suspended sediments samples were collected at the head and mouth of the St. Clair River from 1987 to 1989 for organic contaminant analysis. Higher concentrations and higher frequencies of detection of many organic contaminants. in particular penta- and hexachlorobenzenes, hexachlorobutadiene and octachlorostyrene were measured at the river mouth. Year to year comparisons showed substantial reduction in concentrations of hexachlorobutadiene and octachlorostyrene in suspended sediments.
Trends in Nutrients, Major Ions, Physical Water Quality Parameters and Trace Metals in the Niagara River from 1975 to 1989
Authors: Kuntz Kenneth W. , Tsanis I.K. 
Published: March 2019

Abstract
This paper presents the seasonal and annual variations of the physical parameters, nutrients, major ions and trace metals in the Niagara River for a period of 15 years (1975–89). The discharge during this period was found to be increasing until 1986, after which a large decrease was observed. As a consequence, the specific conductance decreased until 1985 due to the higher dilution effect as well as the lower concentrations of chloride and sodium. High concentrations of total phosphorus during the winter months corresponded with high turbidity and high suspended solids concentrations. In addition, a steady decrease in total phosphorus concentrations was observed until 1984, but since then has levelled off. Nitrate nitrogen concentrations were found to be steadily increasing from 1975 to 1987, and then a large decrease was observed. Both chloride and sodium concentrations decreased substantially from 1975 to 1989, as a result of upstream industrial input decreases, but concentrations since then have levelled off. Iron and aluminum concentrations and loads have shown steady increases since 1975, probably due to increased sediment loads in the October to January period, while lead, nickel, zinc and chromium concentrations and loads are declining.
The Acid-Phase Anaerobic Digestion of Primary Sludge and Its Role in the Biological Phosphorus Removal Process
Authors: Elefsiniotis P. , Oldham W.K. 
Published: March 2019

Abstract
The effects of certain operational and environmental parameters on the acid-phase anaerobic digestion of primary sludge have been investigated using a series of bench-scale, continuous-flow experiments. Short-chain volatile fatty acids (VFA), the main products of the process, are preferred substrates for the bacteria involved in the biological removal of phosphorus. Results show that the net volatile fatty acid generation improves with an increase in hydraulic retention time (up to 12 hours) as well as in solids retention time. Although acid production is not affected by a decrease in pH from 5.1 to 4.5, the production is significantly lower (25 to 30%) at pH of about 6.0. The use of different feed sources influences to some extent the amount of product formation. Moreover, lipid and carbohydrate degradation patterns are dependent on reactor configuration, whereas protein utilization appears to be independent of the reactor regime. The amount of VFA produced, in most cases, is high enough to support biological phosphorus removal processes.
Anaerobic Treatment of Cheese Dairy Wastewater Using the SNC Bioreactor
Authors: Mulligan Catherine N. , Safi Bechara F. , Meunier Jacques , Chebib Jean 
Published: March 2019

Abstract
The SNC multiplate reactor (1,200 L) has been developed and tested to determine chemical oxygen demand (COD) removal, nutrient requirement, and gas production from the anaerobic treatment of effluents generated at the Agropur (Notre Dame-du-Bon-Conseil, Quebec) and Nutrinor cheese dairies (Chambord, Quebec). At the Agropur plant, wastewater (3,000 mg/L COD) was treated the best at a retention time of 12 h. Using this retention time, effluents containing whey with organic loads of 10.2 to 41.6 kg COD/m3/day could be treated at a 84% COD removal rate. When the reactor was subjected to shock by increasing the organic load suddenly from 8.9 to 31 kg COD/m3/day, the total COD removal decreased to 72% and then returned to 86% after 7 days. Hydrology tests indicated that the reactor functions as a series of completely mixed stirred tanks. At Nutrinor, using a 12-h retention time and diluted whey permeate (20,000 mg/L COD), total COD removal was 86% and gas production was 12.0 m3/m3/day for a loading of 36.5 kg COD/m3/day. Nutrient supplementation was not required. For experiments performed with different proportions of wastewater (2,000 mg/L COD) to whey permeate (70,000 mg/L COD) results of 89% total and 93% soluble COD removal with a gas production of 11 m3/m3/day for a loading of 25 kg COD/m3/day were obtained. Retention times were varied from 18 to 60 h to correspond to initial CODs of 20,000 to 70,000 mg/L. In conclusion, this reactor functions in a superior manner to other published anaerobic treatment systems.
Biofiltration Pilot Test at the Daishowa Pulp and Paper Mill Using the Biocarbone Process
Authors: Séguin François A. , Tremblay Bruno , Zaloum Ronald , Lavallée Pierre , Lapointe Serge 
Published: March 2019

Abstract
As a result of increasing industrial activity and stricter application of environmental standards, pressure is being brought on Industries to improve the quality of their effluents. To achieve these goals, cost-efficient and high-performance wastewater treatment processes are needed. Recently, tests were completed on the treatment of ground wood, TMP and de-inking process effluents at the Daishowa, Quebec, pulp and paper mill. The biological treatment used was a fixed-film process known as the “Biocarbone” process. These tests demonstrated conclusively the high effectiveness of the Biocarbone process at COD loads of up to 10 kg/m3.day. This represents a major savings of space when compared to conventional waste activated sludge processes with COD loads of 2-3 kg/m3.day. The object of the test was to verify BOD5 levels, TSS removal and toxicity levels with respect to existing environmental standards. At all times and for all conditions tested, the Biocarbone process met the accepted standards of 5 kg/t of BOD5, 8 kg/t of TSS, and total removal of toxicity on a monthly basis
Mécanismes de toxicité du dinitro-o-crésol dans les chloroplastes
Authors: Pascal Jean , Popovic Radovan 
Published: March 2019

Résumé
L’inhibition du transport d’électron photosynthétique des plantes d’orge (Hordeum vulgarae) par un herbicide phénolique (DNOC) a été étudié. Ces expériences ont été réalisées afin de pouvoir mieux connaître les sites d’inhibition ainsi que les principaux modes d’action de cet herbicide.
Les résultats ont démontré que le DNOC agit en inhibant au contact, du côté donneur et accepteur du PSII simultanément. L’inhibition du côté oxydant, via le complexe de dégagement d’oxygène, est partielle (70%) et semble affecter les PSII situés dans les empilements granaires. Du côté réducteur, l’action du DNOC est plus complexes. Ainsi, à faibles concentration (&lt;10 µM), le DNOC agit comme un accepteur d’électron au niveau de QA. A de plus fortes concentrations, cet herbicide inhibe la chaîne de transport d’électron au niveau du même site ainsi que du côté accepteur du PSII.
Indice de fluorescence algale et variations de pH appliqués à l’étude des effets du pétrole dispersé sur le phytoplancton marin
Authors: Roy Suzanne , Simon Robert , Pelletier Émilien 
Published: March 2019

Résumé
Le suivi environnemental d’une communauté phytoplanctonique lors de l’imposition d’un stress toxique requiert l’utilisation d’indices écotoxicologiques à la fois rapides et sensibles. Dans ce contexte, une série d’expériences en laboratoire et en mésocosmes de 3,5 m3 a été réalisée afin d’établir l’intérêt de deux indices: (!) la fluorescence algale, avant et après empoisonnement avec le DCMU, et (ii) les variations de pH comme indicateurs de toxicité en présence de pétrole dispersé. Ces deux indices se sont révélés capables de suivre l’évolution de l’activité algale sous des conditions expérimentales reflétant l’hiver et le printemps dans les eaux du fleuve Saint-Laurent et des concentrations de pétrole variables. L’indice de fluorescence utilisé, reflet du potentiel photosynthétique, augmente en présence d’une forte croissance algale mais diminue à de très faibles valeurs dans les réservoirs fortement intoxiqués. Le pH subit aussi une augmentation lorsque la croissance phytoplanctonique, ou plus exactement le bilan net photosynthèse-respiration est positif, alors que la toxicité des produits pétroliers est reflétée par une diminution ou une stabilisation du pH. Les effets d’une contamination pétrolière ainsi que les possibilités d’application de ces méthodes sur le terrain et en laboratoire sont discutés.
Toxic Effects of Copper on Selenastrum capricornutum Measured by a Plow Cytometry-Based Method
Authors: Arsenault Guy , Cvetkovic Alexandre D. , Popovic Radovan 
Published: March 2019

Abstract
Adaptation of algae Selenastrum capricornutum to different copper concentrations (50,150,300 and 450 ppb) was investigated. A flow cytometry technique was used to evaluate esterase activity (staining probe: CFDA). Algal physiological stress was estimated by comparing the esterase activity profile of intoxicated samples to that of a control sample. Our results show that at high concentration (450 ppb), copper strongly reduces esterase activity, whereas it increases that activity at lower concentrations (&lt;300 ppb). After 27 hours of incubation, the esterase activity level resumed to the normal profile for each copper concentrations. The esterase activity profile thus shows adaption processes of algae Selenastrum capricornutum to copper intoxication.
Inhibition Mode of S-State Transitions by Sulphate in Oxygen Evolution by Photosystem II Alpha
Authors: Beauregard M. , Meunier P.C. , Popovic R. 
Published: March 2019

Abstract
Thylakoids Incubated with sulphate show an inhibition of oxygen evolution. However, analysis of oxygen production patterns induced by flashes reveals that sulphate treatment does not modify the “miss probability” in the advancement of the S-state cycle. This indicates that the PSII inhibited by sulphate are completely blocked in oxygen evolution, while another part of PSII is left intact. Therefore, the measured oxygen yields originate only from unaffected PSII. Our interpretation is supported by fluorescence measurements, which show a decrease in PSIIalpha fluorescence, while the apparent rate of Qa reduction in active PSIIα is not changed after sulphate treatment. Thus, sulphate induces a complete shut-off of S-state transitions in a part of the PSIIα population, leaving the other part intact; PSIIβ were not affected. This implies that the antagonist actions of chloride and sulphate do not proceed through a fast equilibrium.
Septic Tank Effluent Treatment Using Laboratory-Scale Peat Filters
Authors: Coleman R.N. , Gaudet I.D. 
Published: March 2019

Abstract
Filter columns were designed, constructed from sand, peat and coarse gravel, and their effectiveness assessed in the treatment of septic tank effluent. An initial loading rate of 4 cm/d was applied to the filter columns in either a downward or upward flow at a temperature of 10°C or 20°C. The loading rate was later increased to 8 cm/d. Filter-column plugging occurred in the downward flow treatment but not in the upward flow treatment. Fecal Coliform removal was usually greater than 95%, BOD removal was greater than 75%, and various removal levels were exhibited for other components. Microbial colonization of peat and gravel was effective as revealed by scanning electron microscopy.
Lixiviation biologique des métaux lourds et stabilisation des boues municipales
Authors: Benmoussa H. , Tyagi R.D. , Campbell P.G.C. , Blais J.F. 
Published: March 2019

Résumé
La présence de teneurs élevées en métaux lourds retrouvées dans les boues de stations d’épuration est un facteur important limitant l’épandage agricole de cette biomasse potentiellement fertilisante. Au cours des dernières années, quelques procédés microbiologiques d’extraction des métaux lourds ont été examinés. La mise au point d’un procédé qui permettrait conjointement l’enlèvement des métaux lourds et la stabilisation des boues est évidemment souhaitable. L’approche poursuivie dans cette étude était de vérifier si le procédé microbien de lixiviation des métaux lourds développé dans notre laboratoire pourrait éventuellement remplacer les procédés conventionnels de stabilisation des boues municipales. Les résultats obtenus en cultures discontinues avec des boues secondaires prélevées d’un réacteur biologique séquentiel (RBS) montrent que la forte chute de pH (&lt; 2.5), laquelle est liée directement à la quantité de soufre ajouté à la boue, entraîne une solubilisation importante des métaux (Al: 20–31%, Cd: 81-99%, Cr: 17–43%, Cu: 85–97%, Fe: 13–49%, Mn: 90–100%, Ni: 66–84%, Pb: 20–44%, Zn: 91–97%). De plus, ce procédé permet une réduction appréciable des matières en suspension volatiles (33%), alors que les propriétés fertilisantes des boues traitées sont conservées (N: 90%, P: 100%, K: 100%).