Corsaro D.,University of Lausanne |
Pages G.S.,Aigues de Barcelona |
Catalan V.,Labaqua |
Loret J.-F.,SUEZ Environment |
Greub G.,University of Lausanne
International Journal of Hygiene and Environmental Health | Year: 2010
In this study, we enlarged our previous investigation focusing on the biodiversity of chlamydiae and amoebae in a drinking water treatment plant, by the inclusion of two additional plants and by searching also for the presence of legionellae and mycobacteria. Autochthonous amoebae were recovered onto non-nutritive agar, identified by 18S rRNA gene sequencing, and screened for the presence of bacterial endosymbionts. Bacteria were also searched for by Acanthamoeba co-culture.From a total of 125 samples, we recovered 38 amoebae, among which six harboured endosymbionts (three chlamydiae and three legionellae). In addition, we recovered by amoebal co-culture 11 chlamydiae, 36 legionellae (no L. pneumophila), and 24 mycobacteria (all rapid-growers).Two plants presented a similar percentage of samples positive for chlamydiae (11%), mycobacteria (20%) and amoebae (27%), whereas in the third plant the number of recovered bacteria was almost twice higher. Each plant exhibited a relatively high specific microbiota. Amoebae were mainly represented by various Naegleria species, Acanthamoeba species and Hartmannella vermiformis. Parachlamydiaceae were the most abundant chlamydiae (8 strains in total), and in this study we recovered a new genus-level strain, along with new chlamydiae previously reported. Similarly, about 66% of the recovered legionellae and 47% of the isolated mycobacteria could represent new species. Our work highlighted a high species diversity among legionellae and mycobacteria, dominated by putative new species, and it confirmed the presence of chlamydiae in these artificial water systems. © 2010 Elsevier GmbH.
Martin Ruel S.,CIRSEE |
Esperanza M.,CIRSEE |
Choubert J.-M.,IRSTEA |
Valor I.,Labaqua |
And 2 more authors.
Water Science and Technology | Year: 2010
The next challenge of wastewater treatment is to reliably remove micropollutants at the microgram per litre range in order to reduce the discharge for priority substances and to meet the environmental quality standards set by the European Water Framework Directive. The present work assessed the occurrence of 60 organic substances (priority substances and other relevant pollutants) in municipal wastewater and sludge. Their fate in the treatment processes and their removal efficiencies were quantified. Thorough on-site mass balances were carried out at 8 municipal wastewater treatment plants chosen among conventional and advanced secondary processes. It was found that 70% of the substances were quantified in raw wastewater and 50% in effluent, with a transfer without a limited degradation for most of them. Low loaded activated sludge (AS) process reduced the emission of more than half of micropollutants. At low sludge retention time (AS under high load), lower removal efficiencies were measured compared to low loaded AS. No influence of temperature of the biological reactor was shown. The membrane bioreactor process increased the removal efficiencies for one third of the substances that were partially removed with AS. Still, five substances were measured at concentrations exceeding the environmental quality standards at the outlet of the studied plants. In addition to efforts for source-reduction, complementary treatments need to be set-up. © IWA Publishing 2010.
Martin Ruel S.,CIRSEE |
Choubert J.M.,IRSTEA |
Esperanza M.,CIRSEE |
Miege C.,IRSTEA |
And 5 more authors.
Water Science and Technology | Year: 2011
The next challenge of wastewater treatment is to reliably remove micro-pollutants at the microgram per litre range in order to meet reuse applications and contribute to reach the good status of the water bodies. A hundred priority and relevant emerging substances were measured to evaluate at full-scale the removal efficiencies of seven advanced treatment lines (one membrane bioreactor process and six tertiary treatment lines) that were designed for reuse applications. To reliably compare the processes, specific procedures for micro-pollutants were applied for sampling, analysis and calculation of removal efficiencies. The membrane bioreactor process allowed to upgrade the removal efficiencies of about 20% of the substances measured, especially those that were partially degraded during conventional processes. Conventional tertiary processes like high rate clarification, sand filtration and polishing pond achieved significant removal for some micro-pollutants, especially for adsorbable substances. Advanced tertiary processes, like ozonation, activated carbon and reverse osmosis were all very efficient to complete the removal of polar pesticides and pharmaceuticals; metals and less polar substances were better retained by reverse osmosis. © IWA Publishing 2011.
Jacquet R.,IRSTEA |
Miege C.,IRSTEA |
Smedes F.,Deltares |
Smedes F.,Masaryk University |
And 9 more authors.
Chemosphere | Year: 2014
This study aimed at evaluating and comparing five integrative samplers for the monitoring of indicator and dioxin-like polychlorinated biphenyls (PCBs) in water: semi-permeable membrane device (SPMD), silicone rubber, low-density polyethylene (LDPE) strip, Chemcatcher and a continuous-flow integrative sampler (CFIS). These samplers were spiked with performance reference compounds (PRCs) and then simultaneously exposed under constant agitation and temperature in a 200 L stainless steel tank for periods ranging from one day to three months. A constant PCB concentration of about 1ng·L-1 was achieved by immersing a large amount of silicone rubber sheets ("dosing sheets") spiked with the target PCBs. The uptake of PCBs in the five samplers showed overall good repeatability and their accumulation was linear with time. The samplers SPMD, silicone rubber and LDPE strip were the most promising in terms of achieving low limits of quantification. Time-weighted average (TWA) concentrations of PCBs in water were estimated from uptake of PCBs using the sampling rates calculated from the release of PRCs. Except for Chemcatcher, a good agreement was found between the different samplers and TWA concentrations ranged between 0.4 and 2.8 times the nominal water concentration. Finally, the influence of calculation methods (sampler-water partition coefficients, selected PRCs, models) on final TWA concentrations was studied. © 2013 Elsevier Ltd.
PubMed | IRSTEA, Masaryk University, University of Nantes, Suez Environnement CIRSEE and 3 more.
Type: | Journal: Chemosphere | Year: 2014
This study aimed at evaluating and comparing five integrative samplers for the monitoring of indicator and dioxin-like polychlorinated biphenyls (PCBs) in water: semi-permeable membrane device (SPMD), silicone rubber, low-density polyethylene (LDPE) strip, Chemcatcher and a continuous-flow integrative sampler (CFIS). These samplers were spiked with performance reference compounds (PRCs) and then simultaneously exposed under constant agitation and temperature in a 200 L stainless steel tank for periods ranging from one day to three months. A constant PCB concentration of about 1 ngL(-1) was achieved by immersing a large amount of silicone rubber sheets (dosing sheets) spiked with the target PCBs. The uptake of PCBs in the five samplers showed overall good repeatability and their accumulation was linear with time. The samplers SPMD, silicone rubber and LDPE strip were the most promising in terms of achieving low limits of quantification. Time-weighted average (TWA) concentrations of PCBs in water were estimated from uptake of PCBs using the sampling rates calculated from the release of PRCs. Except for Chemcatcher, a good agreement was found between the different samplers and TWA concentrations ranged between 0.4 and 2.8 times the nominal water concentration. Finally, the influence of calculation methods (sampler-water partition coefficients, selected PRCs, models) on final TWA concentrations was studied.
Bergeron P.,Rivages Pro Technology Technopole Izarbel |
Oujati H.,Lonza Bioscience SAS |
Catalan Cuenca V.,Labaqua |
Huguet Mestre J.M.,Aigues de Barcelona |
Courtois S.,Suez Environment CIRSEE
International Journal of Hygiene and Environmental Health | Year: 2011
For accompanying actions to pollution crisis management of recreational waters, rapid methods providing a quantified faecal indicator which can be completed in less than half a day, are currently needed. Two sensitive rRNA-targeted Reverse Transcription-quantitative PCR (RT-qPCR) methods were developed for quantifying Escherichia coli and Enterococcus spp. cells in marine bathing waters. Threshold cycle (Ct) values were found to be linear with a target quantity over a 4log dynamic range (from 105 to 100 cell equivalents per 100ml). In order to confirm the scope of application of such alternative methods, 80 and 85 seawater samples from the Atlantic Ocean and Mediterranean sea were analysed by both RT-qPCR and ISO culture-based methods for E. coli and Enterococcus spp. enumerations. This study demonstrates that by giving reliable results in 3. h, the RT-qPCR method has high potential as a rapid test for recreational water quality monitoring. In natural waters, significant linear log-log relations between the RT-qPCR and culture method measurements for E. coli and Enterococcus spp. assays were shown (correlation coefficient (r) values of 0.814 and 0.715, p< 0.0001, respectively). The sensitivities (defined as the probability of a sample testing positive if the criterion number is exceeded) of RT-qPCR for E. coli and Enterococcus spp. were respectively 94.4% and 83.9%. By contrast, specificities (defined as the probability of a test being negative if a contamination is truly absent) could be considered as lower (65.9% and 50.0% for E. coli and Enterococcus spp.). This reflects that RT-qPCR assays detect all viable cells (culturable and non-culturable) whereas culture methods only detect cells which are viable and culturable. © 2011 Elsevier GmbH.
Ventura F.,AGBAR. Aigues de Barcelona |
Quintana J.,AGBAR. Aigues de Barcelona |
Gomez M.,Labaqua |
Velo-Cid M.,Augas de Galicia
Bulletin of Environmental Contamination and Toxicology | Year: 2010
A study of organic compounds which caused several odor problems in water supplies from NW Spain was carried out. Sour dish-cloths, potato bin and musty were the main descriptors associated with these events. Closed loop stripping analysis combined with sensory-GC and GC/MS detection was used. The compound producing the initial odor event was 3,5-dimethyl-2-methoxypyrazine, identified for the first time as the compound responsible for odor incidents in finished water. Concentration levels were up to 300 ng/L in the effluent from an activated sludge wastewater treatment plant (WWTP) and 3 ng/L in finished water. 3-isobutyl-2-methoxypyrazine and other alkyl methoxypyrazines were the compounds responsible for the odor events that occurred several months later. Concentration levels in the mg/L range were measured in the activated sludge of a WWTP. © 2010 Springer Science+Business Media, LLC.
Ubilla P.,Aqualogy |
Clavijo D.,ANAM Anlisis Ambientales |
Helgu'n R.,ANAM Anlisis Ambientales |
Cerda R.,LABAQUA |
And 2 more authors.
Chemical Engineering Transactions | Year: 2016
The relationship between the odours emitted by a given facility and the influence they cause on the population living in the surrounding area is very complex to determine, because this relationship include objective physical and chemical components, which are easily measured, as well as subjective elements which are much more difficult to evaluate. Nowadays there are Standarized Methodologies in order to obtain a reliable and complemented odour impact assessment. The application of these methodologies allows to assess the problem in a standardized way, and from technical and economical point of view. The most used methodologies are emission-based studies (EN-13725 / NCh 3190) and, immission-based studies (VDI 3940); and can be complemented by chemical analysis and complain management. Depending on the complexity and scope of the project, several methodologies can be used in order to obtain information from different points of view. This approach considering several methodologies has been carried out at the Municipality of 'San Francisco de Mostazal', in Chile, by means of conversations between the Authority, Companies and the Community. It was required a comprehensive study based on emission studies according to EN-13725/NCh 3190, complaint management (VDI 3883) and, chemical analysis (VOCs, H2S and NH3). As a result of this study, it was possible to determine the nuisance degree, possible origin, and therefore, the best way to face it. © 2016, AIDIC Servizi S.r.l.
Schlosser O.,Analysis and Health Division |
Huyard A.,Analysis and Health Division |
Water Science and Technology | Year: 2011
The objective of this study was to assess workers' exposure to bioaerosols in sludge drying units. Simultaneous collection of inhalable dust and airborne biological agents was carried out using rotating cup samplers (CIP 10, Arelco). Sixteen stationary and 30 personal measurements were performed in three drying plants, during summer and winter. Microbial content of air was characterized by high amounts of Gram-negative bacteria, endotoxin, and thermophilic actinomycetes. High differences between exposure levels were observed with regard to workplaces and tasks. Dryers and conveyors in operation were closed, and the monitoring task in the dryer room was associated with low levels of personal exposure, close to background levels. Conversely, cleaning and maintenance of the dryer and conveyors required the equipment to be opened, giving significantly higher task-based personal exposure levels. The fall of dried sludge into indoor containers resulted in high emission and spreading of dust. Mean personal exposure levels to fungi were moderate or low for all tasks. Based on the results of this study, appropriate means of operational control and personal protection are being developed and implemented on sites. © IWA Publishing 2011.