Boily M.,University of Quebec at Montréal |
Sarrasin B.,Center dexpertise en analyse environnementale du Quebec |
DeBlois C.,Center dexpertise en analyse environnementale du Quebec |
Chagnon M.,University of Quebec at Montréal
Environmental Science and Pollution Research | Year: 2013
In Québec, as observed globally, abnormally high honey bee mortality rates have been reported recently. Several potential contributing factors have been identified, and exposure to pesticides is of increasing concern. In maize fields, foraging bees are exposed to residual concentrations of insecticides such as neonicotinoids used for seed coating. Highly toxic to bees, neonicotinoids are also reported to increase AChE activity in other invertebrates exposed to sub-lethal doses. The purpose of this study was therefore to test if the honey bee's AChE activity could be altered by neonicotinoid compounds and to explore possible effects of other common products used in maize fields: atrazine and glyphosate. One week prior to pollen shedding, beehives were placed near three different field types: certified organically grown maize, conventionally grown maize or non-cultivated. At the same time, caged bees were exposed to increasing sub-lethal doses of neonicotinoid insecticides (imidacloprid and clothianidin) and herbicides (atrazine and glyphosate) under controlled conditions. While increased AChE activity was found in all fields after 2 weeks of exposure, bees close to conventional maize crops showed values higher than those in both organic maize fields and non-cultivated areas. In caged bees, AChE activity increased in response to neonicotinoids, and a slight decrease was observed by glyphosate. These results are discussed with regard to AChE activity as a potential biomarker of exposure for neonicotinoids. © 2013 Springer-Verlag Berlin Heidelberg.
Badjagbo K.,University of Montréal |
Badjagbo K.,EST Inc |
Heroux M.,Environment Canada |
Alaee M.,Environment Canada |
And 2 more authors.
Environmental Science and Technology | Year: 2010
Landfill-biogas utilization is a win-win solution as it creates sources of renewable energy and revenue while diminishing greenhouse gas emissions. However, the combustion of a siloxane-containing biogas produces abrasive microcrystalline silica that causes severe and expensive damages to power generation equipment. Hence, the importance of siloxane analysis of the biogas has increased with the growth of the waste-to-energy market. We have investigated an improved method for the analysis of octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5) in biogas using deuterated hexamethyldisiloxane (HMDS-d18) as an internal standard with direct atmospheric pressure chemical ionization/tandem mass spectrometry (APCI-MS/MS). The use of HMDS-d18 as a single internal standard provided effective signal compensation for both D4 and D5 in biogas and improved the sensitivity and reliability for the direct APCI-MS/MS quantification of these compounds in biogas. Low detection limits (∼2 μg/m3) were achieved. The method was successfully applied for the determination of D4 and D5 contents in various samples of biogas recovered for electrical power generation from a landfill site in Montreal. Concentrations measured for D4 and D5 were in the ranges of 131-1275 and 250-6226 μg/m3, respectively. Among the various landfill zones sampled, a clear trend of decreasing D4 and D5 concentrations was observed for older landfill materials. © 2010 American Chemical Society.
Desrosiers M.,IRSTEA |
Desrosiers M.,Center dexpertise en analyse environnementale du Quebec |
Babut M.P.,IRSTEA |
Pelletier M.,Environment Canada |
And 3 more authors.
Integrated Environmental Assessment and Management | Year: 2010
Multitiered frameworks that are designed for risk assessment of contaminated sediment rely on sediment quality guidelines (SQGs) at the first tier or screening level. In the case of contamination by multiple pollutants, results can be aggregated under indices such as the mean quotient. A decision is then reached (e.g., to dispose of dredged materials in open water) without further investigation, provided that the SQGs or the specific values of indices or quotients derived from the SQGs are not exceeded. In this way, SQGs and quotients play a critical role in environmental protection. As part of the development of a tiered framework to assess the environmental risk of materials dredged from the St. Lawrence River, we evaluated various quotients based on SQGs available for this river with a data set that matches chemistry and toxicity test endpoints. The overall efficiency o all tested quotients was rather low, and we then examined factors such as sediment grain size, nutrients, metal-binding phases (e.g., Al, Fe), and dissolved organic carbon to explain misclassified samples. This examination led to the design of a modified tier 1 framework in which SQGs are used in combination with decision rules based on certain explanatory factors. Integr Environ Assess Manag 2010;6:225-239. ©2009 SETAC.
Farcy E.,Environment Canada |
Farcy E.,Institute Armand Frappier |
Gagne F.,Environment Canada |
Martel L.,Center dExpertise en Analyse Environnementale du Quebec |
And 4 more authors.
Environmental Research | Year: 2011
The aim of this study was to investigate the short-term effects of tertiary-treated municipal effluents on the freshwater mussel Elliptio complanata. Caged mussels were immersed during 2 weeks in a river located North of Montreal Island, upstream/downstream the outfall and in one reference site located at the beginning of the Rivière des Prairies. A selection of biomarkers was analyzed to depict changes on various physiological systems: general physiology (mussel viability, condition index and gonado-somatic index), immune status (hemocyte viability, cellularity, phagocytosis efficiency, NK-like cytotoxic activity and lysozyme activity), inflammation (cyclo-oxygenase activity), detoxification (glutathione-S-transferases activity) and vitellogenesis (alkali-labile phosphate level). The analysis of total and fecal coliform counts in water and of heterotrophic bacteria levels in mussel tissues showed that the bacteriological quality of the water strongly decreased from the reference site to the downstream site. This was correlated with a significant loss of weight and an increase of mussel mortality. Cellularity and phagocytosis efficiency were significantly increased in the downstream site compared to the reference site. Though not statistically significant, lysozyme activity was also increased. NK-like cytotoxicity, activity of the pro-inflammatory enzyme COX and the levels of ALP and MT were not significantly changed. Conversely, the municipal effluents induced a significant increase of GST activity in downstream site, indicating a stimulation of detoxification metabolism. Altogether, these results confirm that a short-term exposure to a mixture of bacterial and chemical compounds released by the wastewater treatment plant La Pinière induces adverse physiological effects in E. complanata, as observed with the modulation of immune response and induction of detoxification metabolism. © 2011.
Van den Brink P.J.,Wageningen University |
Alexander A.C.,University of New Brunswick |
Desrosiers M.,Center dexpertise en analyse environnementale du Quebec |
Goedkoop W.,Swedish University of Agricultural Sciences |
And 3 more authors.
Integrated Environmental Assessment and Management | Year: 2011
We discuss the application of traits-based bioassessment approaches in retrospective bioassessment as well as in prospective ecological risk assessments in regulatory frameworks. Both approaches address the interaction between species and stressors and their consequences at different levels of biological organization, but the fact that a specific species may be less abundant in a potentially impacted site compared with a reference site is, regrettably, insufficient to provide diagnostic information. Species traits may, however, overcome the problems associated with taxonomy-based bioassessment. Trait-based approaches could provide signals regarding what environmental factors may be responsible for the impairment and, thereby, provide causal insight into the interaction between species and stressors. For development of traits-based (TBA), traits should correspond to specific types of stressors or suites of stressors. In this paper, a strengths, weaknesses, opportunities, and threats (SWOT) analysis of TBA in both applications was used to identify challenges and potentials. This paper is part of a series describing the output of the TERA (Traits-based ecological risk assessment: Realising the potential of ecoinformatics approaches in ecotoxicology) Workshop held between 7 and 11 September, 2009, in Burlington, Ontario, Canada. The recognized strengths were that traits are transferrable across geographies, add mechanistic and diagnostic knowledge, require no new sampling methodology, have an old tradition, and can supplement taxonomic analysis.Weaknesses include autocorrelation, redundancy, and inability to protect biodiversity directly. Automated image analysis, combined with genetic and biotechnology tools and improved data analysis to solve autocorrelation problems were identified as opportunities, whereas low availability of trait data, their transferability, their quantitative interpretation, the risk of developing nonrelevant traits, low quality of historic databases, and their standardization were listed as threats. © 2011 SETAC.
Zamyadi A.,Ecole Polytechnique de Montréal |
Dorner S.,Ecole Polytechnique de Montréal |
Sauve S.,University of Montréal |
Ellis D.,Direction des politiques de leau |
And 3 more authors.
Water Research | Year: 2013
Accumulation and breakthrough of several potentially toxic cyanobacterial species within drinking water treatment plants (DWTP) have been reported recently. The objectives of this project were to test the efficiency of different treatment barriers in cyanobacterial removal. Upon observation of cyanobacterial blooms, intensive sampling was conducted inside a full scale DWTP at raw water, clarification, filtration and oxidation processes. Samples were taken for microscopic speciation/enumeration and microcystins analysis. Total cyanobacteria cell numbers exceeded World Health Organisation and local alert levels in raw water (6,90,000 cells/mL). Extensive accumulation of cyanobacteria species in sludge beds and filters, and interruption of treatment were observed. Aphanizomenon cells were poorly coagulated and they were not trapped efficiently in the sludge. It was also demonstrated that Aphanizomenon cells passed through and were not retained over the filter. However, Microcystis, Anabaena, and Pseudanabaena cells were adequately removed by clarification and filtration processes. The breakthrough of non toxic cyanobacterial cells into DWTPs could also result in severe treatment disruption leading to plant shutdown. Application of intervention threshold values restricted to raw water does not take into consideration the major long term accumulation of potentially toxic cells in the sludge and the risk of toxins release. Thus, a sampling regime inside the plant adapted to cyanobacterial occurrence and intensity is recommended. © 2013 Elsevier Ltd.
Giral M.,Ecole Polytechnique de Montréal |
Zagury G.J.,Ecole Polytechnique de Montréal |
Deschenes L.,Ecole Polytechnique de Montréal |
Blouin J.-P.,Center dexpertise en analyse environnementale du Quebec
Environmental Pollution | Year: 2010
Inorganic arsenic in soils poses an important environmental concern. Several studies reported an oxidation of arsenite to arsenate during its extraction from soils. The objectives of this study were to (1) identify, among published procedures, an extraction method which preserves the oxidation state of arsenic and (2) to assess the influence of soil physicochemical properties on the performance of these methods. Four extraction strategies were compared: 1) 10 M HCl, 2) 15% (v/v) H3PO4, 3) 10 mM phosphate + 0.5% (w/v) NaDDC, and, 4) 1 M H3PO4 + 0.5 M ascorbic acid (C6H8O6). Separation and analysis of As species was performed by HPLC-ICP/MS. Oxidation of As(III) into As(V) during extraction was more important in soils with high content of Mn oxides. Extraction of arsenic from soils with 1 M H3PO4 + 0.5 M C6H8O6 under microwaves was the best strategy to extract the majority of As while minimizing conversion of As(III) into As(V). © 2009 Elsevier Ltd. All rights reserved.
Paquet N.,INRS - Institute National de la Recherche Scientifique |
Paquet N.,Center dexpertise en analyse environnementale du Quebec |
Lavoie M.,INRS - Institute National de la Recherche Scientifique |
Lavoie M.,Laval University |
And 4 more authors.
Environmental Toxicology and Chemistry | Year: 2015
Predicting metal availability and toxicity for chronic (several hours or days) metal exposure scenarios, even for unicellular algae, is a major challenge to existing toxicity models. This is because several factors affecting metal uptake and toxicity, such as the release of metal-binding exudates, changes in the kinetics of metal uptake and toxicity over time, and algal physiological acclimation to internalized metals, are still poorly understood. The present study assessed the influence of these factors on Cd uptake and toxicity in laboratory batch cultures of the freshwater alga Pseudokirchneriella subcapitata. To do so, changes in the free Cd2+ concentrations caused by the release of metal-binding algal exudates were monitored,109Cd accumulation in algal cells was measured, and Cd-induced inhibition of algal growth as a function of exposure time (from 12h to 96h) was followed. Results indicate that metal-binding exudates may decrease the proportion of the free Cd2+ ion in solution up to 2-fold, a decrease that affects Cd uptake and toxicity. Pseudokirchneriella subcapitata has the capacity to decrease net Cd uptake rate on short time scales (<24h), but this reduction in the Cd uptake rate disappeared after 24h, and Cd toxicity occurred at relatively high Cd concentrations in solution. These data illustrate some of the pitfalls of standard algal toxicity assays, which were designed for acute exposures, and suggest how robust chronic bioassays might be developed. Environ Toxicol Chem 2015;34:1524-1532. © 2015 SETAC.
Clement B.J.P.,University of Lyon |
Delhaye H.L.,University of Lyon |
Triffault-Bouchet G.G.,Center dexpertise en analyse environnementale du Quebec
Ecotoxicology and Environmental Safety | Year: 2014
Since 1997, we have been developing a protocol for ecotoxicological bioassays in 2-L laboratory microcosms and have applied it to the study of various pollutants and ecotoxicological risk assessment scenarios in the area of urban facilities and transport infrastructures. The effects on five different organisms (micro-algae, duckweeds, daphnids, amphipods, chironomids) are assessed using biological responses such as growth, emergence (chironomids), reproduction (daphnids) and survival, with a duration of exposure of 3 weeks. This bioassay has mainly been used as a batch bioassay, i.e., the water was not renewed during the test. A flow-through microcosm bioassay has been developed recently, with the assumption that conditions for the biota should be improved, variability reduced, and the range of exposure patterns enlarged (e.g., the possibility of maintaining constant exposure in the water column). This paper compares the results obtained in batch and flow-through microcosm bioassays, using cadmium as a model toxicant. As expected, the stabilization of physico-chemical parameters, increased organism fitness and reduced variability were observed in the flow-through microcosm bioassay. © 2014 Elsevier Inc.
Environmental Occurrence of Perfluoroalkyl Acids and Novel Fluorotelomer Surfactants in the Freshwater Fish Catostomus commersonii and Sediments Following Firefighting Foam Deployment at the Lac-Mégantic Railway Accident
PubMed | Center dexpertise en analyse environnementale du Quebec, CNRS Laboratory of Oceanic Environments and Paleo-environments (EPOC), University of Montréal and McGill University
Type: | Journal: Environmental science & technology | Year: 2017
On July 6th 2013, an unmanned train laden with almost 8 million liters of crude oil careened off the rails downtown Lac-Mgantic (Qubec, Canada). In the aftermath of the derailment accident, the emergency response entailed the deployment of 33000 L of aqueous film forming foam (AFFF) concentrate that contained proprietary fluorosurfactants. The present study examines the environmental occurrence of perfluoroalkyl acids (PFAAs) and newly identified per and polyfluoroalkyl substances (PFASs) in the benthic fish white sucker (Catostomus commersonii) and sediments from Lake Mgantic and Chaudire River. In sediments, PFAAs displayed relatively low concentrations (PFAAs = 0.06-0.5 ng g0.28-2.1 ng g