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Rodriguez, Manuel J.

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Manuel J.
Université Laval. Faculté d'aménagement, d'architecture, d'art et de design
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Voici les éléments 1 - 8 sur 8
  • Publication
    Accès libre
    Domestic water security in the Arctic : a scoping review
    (Elsevier, 2022-11-19) Cassivi, Alexandra; Covey, Anna; Rodriguez, Manuel J.; Guilherme, Stéphanie
    Introduction: More than 50 million people living in the Arctic nations remain without access to safely managed drinking water services. Remote northern communities, where large numbers of Indigenous peoples live, are disproportionally affected. Recent research has documented water and health-related problems among Indigenous communities, including poor water quality and insufficient quantities of water. Objective: The objective of this scoping review is to examine the extent of available water security evidence as well as identify research gaps and intervention priorities to improve access to domestic water in the Arctic and Subarctic regions of the eight Arctic nations (Canada, the Kingdom of Denmark (Greenland), Finland, Iceland, Norway, Sweden, Russia, and the United States (Alaska)). Methods: An extensive literature review was conducted to retrieve relevant documentation. Arctic & Antarctic Regions, Compendex, Geobase, Georef, MEDLINE and Web of Science databases were searched to identify records for inclusion. The initial searches yielded a total of 1356 records. Two independent reviewers systematically screened identified records using selection criteria. Descriptive analyses were used to summarize evidence of included studies. Results: A total of 55 studies, mostly conducted in Canada and the United States, were included and classified by four predetermined major dimensions: 1) Water accessibility and availability; 2) Water quality assessment; 3) Water supply and health; 4) Preferences and risk perceptions. Conclusions: This scoping review used a global approach to provide researchers and stakeholders with a summary of the evidence available regarding water security and domestic access in the Arctic. Culturally appropriate health-based interventions are necessary to ensure inclusive water services and achieve the Sustainable Development Goals (SDG) targets for universal access to water.
  • Publication
    Accès libre
    Identification of dichloroacetic acid degrading Cupriavidus bacteria in a drinking water distribution network model
    (Blackwell Science, 2013-10-17) Duchaine, Caroline; Sérodes, Jean-Baptiste; Jubinville, Éric; Rodriguez, Manuel J.; Fournier-Larente, Jade; Berthiaume, C.; Gilbert, Yan.; Fillion, G.; Charette, Steve; Pluchon, Cécile
    Aims Bacterial community structure and composition of a drinking water network were assessed to better understand this ecosystem in relation to haloacetic acid (HAA) degradation and to identify new bacterial species having HAA degradation capacities. Methods and Results Biofilm samples were collected from a model system, simulating the end of the drinking water distribution network and supplied with different concentrations of dichloroacetic and trichloroacetic acids at different periods over the course of a year. The samples were analysed by culturing, denaturing gradient gel electrophoresis (DGGE) and sequencing. Pipe diameter and HAA ratios did not impact the bacterial community profiles, but the season had a clear influence. Based on DGGE profiles, it appeared that a particular biomass has developed during the summer compared with the other seasons. Among the bacteria isolated in this study, those from genus Cupriavidus were able to degrade dichloroacetic acid. Moreover, these bacteria degrade dichloroacetic acid at 18°C but not at 10°C. Conclusions The microbial diversity evolved throughout the experiment, but the bacterial community was distinct during the summer. Results obtained on the capacity of Cupriavidus to degrade DCAA only at 18°C but not at 10°C indicate that water temperature is a major element affecting DCAA degradation and confirming observations made regarding season influence on HAA degradation in the drinking water distribution network. Significance and Impact of the Study This is the first demonstration of the HAA biodegradation capacity of the genus Cupriavidus.
  • Publication
    Accès libre
    Open the SterivexTM casing : an easy and effective way to improve DNA extraction yields
    (Wiley, 2017-10-31) Cruaud, Perrine; Culley, Alexander; Vigneron, Adrien; Rodriguez, Manuel J.; Fradette, Marie-Stéphanie; Dorea, Caetano Chang; Charette, Steve
    We describe an inexpensive, reliable, and easily executed improvement for the extraction of DNA from SterivexTM filter units, that involves the separation of the SterivexTM filter from its casing. Our study demonstrates that our modification of the original extraction protocol significantly increased DNA yields, with an average increase of 4.1‐fold more DNA than with the standard approach. A comparison of the diversity after Illumina MiSeq sequencing of bacterial communities extracted with both the standard approach and the proposed one indicated that our modified protocol has no or little impact on the results. This protocol provides a relatively straight forward means to achieve higher yields of DNA from the extraction of SterivexTM cartridges without altering the community composition and will likely be of interest to a wide range of scientists that use techniques based on the recovery of DNA from filters.
  • Publication
    Modelling the regional variability of the probability of high trihalomethane occurrence in municipal drinking water
    (Springer, 2015-11-12) Cool, Geneviève; Rodriguez, Manuel J.; Sadiq, Rehan; Lebel, Alexandre
    The regional variability of the probability of occurrence of high total trihalomethane (TTHM) levels was assessed using multilevel logistic regression models that incorporate environmental and infrastructure characteristics. The models were structured in a three-level hierarchical configuration: samples (first level), drinking water utilities (DWUs, second level) and natural regions, an ecological hierarchical division from the Quebec ecological framework of reference (third level). They considered six independent variables: precipitation, temperature, source type, seasons, treatment type and pH. The average probability of TTHM concentrations exceeding the targeted threshold was 18.1 %. The probability was influenced by seasons, treatment type, precipitations and temperature. The variance at all levels was significant, showing that the probability of TTHM concentrations exceeding the threshold is most likely to be similar if located within the same DWU and within the same natural region. However, most of the variance initially attributed to natural regions was explained by treatment types and clarified by spatial aggregation on treatment types. Nevertheless, even after controlling for treatment type, there was still significant regional variability of the probability of TTHM concentrations exceeding the threshold. Regional variability was particularly important for DWUs using chlorination alone since they lack the appropriate treatment required to reduce the amount of natural organic matter (NOM) in source water prior to disinfection. Results presented herein could be of interest to authorities in identifying regions with specific needs regarding drinking water quality and for epidemiological studies identifying geographical variations in population exposure to disinfection by-products (DBPs).
  • Publication
    Impact of catchment geophysical characteristics and climate on the regional variability of dissolved organic carbon (DOC) in surface water
    (Elsevier, 2014-06-07) Cool, Geneviève; Rodriguez, Manuel J.; Sadiq, Rehan; Lebel, Alexandre
    Dissolved organic carbon (DOC) is a recognized indicator of natural organic matter (NOM) in surface waters. The aim of this paper is twofold: to evaluate the impact of geophysical characteristics, climate and ecological zones on DOC concentrations in surface waters and, to develop a statistical model to estimate the regional variability of these concentrations. In this study, multilevel statistical analysis was used to achieve three specific objectives: (1) evaluate the influence of climate and geophysical characteristics on DOC concentrations in surface waters; (2) compare the influence of geophysical characteristics and ecological zones on DOC concentrations in surface waters; and (3) develop a model to estimate the most accurate DOC concentrations in surface waters. The case study involved 115 catchments from surface waters in the Province of Quebec, Canada. Results showed that mean temperatures recorded 60 days prior to sampling, total precipitation 10 days prior to sampling and percentages of wetlands, coniferous forests and mixed forests have a significant positive influence on DOC concentrations in surface waters. The catchment mean slope had a significant negative influence on DOC concentrations in surface waters. Water type (lake or river) and deciduous forest variables were not significant. The ecological zones had a significant influence on DOC concentrations. However, geophysical characteristics (wetlands, forests and slope) estimated DOC concentrations more accurately. A model describing the variability of DOC concentrations was developed and can be used, in future research, for estimating DBPs in drinking water as well evaluating the impact of climate change on the quality of surface waters and drinking water.
  • Publication
    Investigating social inequalities in exposure to drinking water contaminants in rural areas
    (Applied Science Publishers, 2015-09-11) Rodriguez, Manuel J.; Benmarhnia, Tarik; Lebel, Alexandre; Delpla, Ianis; Levallois, Patrick
    Few studies have assessed social inequalities in exposure to drinking water contaminants. This study explores this issue in 593 rural municipalities of Québec, Canada. Quartiles of an ecological composite deprivation index were used as a proxy of socioeconomic status. Total trihalomethanes (TTHMs) and lead were chosen as proxies of chemical drinking water quality. The results show that the majority of deprived rural municipalities apply no treatment to their water (26%) or use a basic treatment (51%), whereas a relative majority of the wealthiest municipalities (40%) use advanced treatment. The proportion of municipalities having important lead (>5 µg/L) levels is highest in most deprived municipalities. Moreover, most deprived municipalities have a higher risk of high tap lead levels (RR = 1.33; 95%CI: 1.30, 1.36). Conversely, most deprived municipalities have a lower risk of high TTHMs levels (RR = 0.78; 95%CI: 0.69, 0.86). These findings suggest an environmental inequality in drinking water contaminants distribution in rural municipalities.
  • Publication
    Low concentrations of bromodichloromethane induce a toxicogenomic response in porcine embryos in vitro
    (Reproductive Toxicology Center, 2016-09-23) Pagé-Larivière, Florence; Tremblay, Amélie; Rodriguez, Manuel J.; Campagna, Céline; Sirard, Marc-André
    Bromodichloromethane (BDCM) is one of the trihalomethanes present in chlorinated water. Humans are thus daily exposed. Previous contradictory results failed to clearly establish the adverse effects of low concentrations of BDCM. By using the porcine preimplantation embryo as a sensitive model, we showed that exposure to low concentrations of BDCM (10 and 100 ppb) during the first week of embryo development induced adverse effect on the blastocyst rate and alteration of the estradiol pathway. Our results also suggest that blastocysts exposed to BDCM present transcriptomic and epigenomic adaptive modifications compatible with the cardiac anomalies observed by previous studies of newborns exposed to BDCM during gestation. Thus, phenotypic observations and toxicogenomic adaptations of embryo to low concentration of BDCM provide insights for BDCM risk assessment. Indeed, our results support the use of sensitive toxicogenomic models using environmentally relevant concentrations to which humans are exposed in order to conduct the risk assessment.
  • Publication
    Haloacetic acid degradation by a biofilm in a simulated drinking water distribution system
    (IWA Publishing, 2013-03-01) Duchaine, Caroline; Sérodes, Jean-Baptiste; Pluchon, Cécile; Rodriguez, Manuel J.; Fournier-Larente, Jade; Berthiaume, C.; Gilbert, Yan.; Fillion, G.; Charette, Steve
    Haloacetic acids (HAAs) are disinfection by-products formed as a result of the reaction between chlorine and natural organic matter found in water. HAA concentrations have been observed to decrease at distribution system extremities. This decrease is associated with microbiological degradation by pipe wall biofilm. The objective of this study was to evaluate HAA degradation in a drinking water system in the presence of a biofilm and to identify the factors that influence this degradation. Degradation of dichloracetic acid (DCAA) and trichloroacetic acid (TCAA) was observed in a simulated distribution system. The results obtained showed that different parameters came into play simultaneously in the degradation of HAAs, including retention time, water temperature, biomass, composition of organic matter, and pipe diameter. Seasonal variations had a major effect on HAA degradation and biomass quantity was lower by 1 to 2 logs in the winter and spring compared with the fall. HAA removal decreased with increasingly large pipe diameters. The specific effects of each of these factors were difficult to isolate from each other owing to interactions.