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Upgrading the Performance of Urban Wastewater Facultative Ponds by changing to Attached Baffled Process Полный текст
2018
Sasani, Hossein | Mehrdadi, Naser | Aminzadeh, Behnoush | Takdastan, Afshin
This study aims at evaluating the improved facultative ponds performance in pilot scale. Wastewater has been collected from primary settling basins of Ahvaz wastewater treatment plant. Treatment efficacy of the four systems (three systems in parallel with a control system) has been evaluated over a period of 12 months at various hydraulic retention times (HRT) and organic loading rates (OLR). There has been no baffle and no attached growth media (AGM) in the control system (S0), while other three systems (S2, S3, and S4) have been equipped with different numbers of baffles and AGM packages, containing the mineral shells. Results show that efficiency of BOD5 removal for S0, S2, S3, and S4 are 53.4%, 60.8%, 64.7%, and 67.6%, respectively, while for COD these rates alter to 28.1%, 37.7%, 45.8%, and 50.1 % and of coliform to 66.7%, 76.6%, 80.7%, and 83.4%. Filtered BOD5 in the effluent of S0, S2, S3, and S4 is 32.5, 27.6, 24.6, and 22.3 mg/l, respectively and 60.2, 52.1, 47, and 44.3 mg/l for TSS. Also the 10-day HRT has been optimum among applied HRTs. As such, attached growth-baffled ponds function better than conventional ones, making the technique, examined in the present paper a low-cost process to establish new wastewater treatment plants or upgrading the existent WSPs, especially in case of warm areas of southwestern Iran.
Показать больше [+] Меньше [-]Estimation of Annual Effective Dose of 222 Rn and 220 Rn in indoor Air of Rohilkhand region, Uttar Pradesh state, India Полный текст
2018
Rastogi, N. | Singh, I. | Goswami, V.
The annual exposure to indoor radon and thoron imparts a major contribution to inhalation doses received by the public. In this study, we report results of time integrated passive of indoor radon and thoron concentrations that were carried out in Rohilkhand region with health risk to the dwellers in the region. In present study, Solid State Nuclear Track Detectors (SSNTDS ) based twin chamber dosimeter with LR-115 track detector were used for estimating Radon (222Rn) and Thoron (220Rn) gas concentration levels in the dwellings of Moradabad city. The average Radon and thoron concentration levels in the studied dwellings were found to vary from 13.5 to 21.8 Bq m-3 and thoron concentrations is found to vary from 11.7 to 19.5 Bqm-3 and its corresponding geometric mean of equilibrium-equivalent 222Rn and 220Rn concentration were found 7.07 to 1.7 Bqm-3 . The total annual effective dose due to the exposure to radon and thoron was found to vary from3.7 to 6.2 mSv/y whereas from thoron found to vary from 0.3 to 0.61 mSv/y.
Показать больше [+] Меньше [-]Contaminants in Atlantic walruses Part 2: Relationships with endocrine and immune systems Полный текст
2018
Routti, Heli | Diot, Beatrice | Panti, Cristina | Duale, Nur | Fossi, Maria Cristina | Harju, Mikael | Kovacs, Kit M. | Lydersen, Christian | Scotter, Sophie | Villanger, Gro Dehli | Bourgeon, Sophie
Contaminants in Atlantic walruses Part 2: Relationships with endocrine and immune systems Полный текст
2018
Routti, Heli | Diot, Beatrice | Panti, Cristina | Duale, Nur | Fossi, Maria Cristina | Harju, Mikael | Kovacs, Kit M. | Lydersen, Christian | Scotter, Sophie | Villanger, Gro Dehli | Bourgeon, Sophie
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Показать больше [+] Меньше [-]Contaminants in Atlantic walruses Part 2: Relationships with endocrine and immune systems Полный текст
2018
Routti, Heli | Diot, Beatrice | Panti, Cristina | Duale, Nur | Fossi, Maria Cristina | Harju, Mikael | Kovacs, Kit M. | Lydersen, Christian | Scotter, Sophie | Villanger, Gro Dehli | Bourgeon, Sophie
Accepted manuscript version. Published version available at <a href=https://doi.org/10.1016/j.envpol.2018.11.097> https://doi.org/10.1016/j.envpol.2018.11.097</a>. Licensed <a href=http://creativecommons.org/licenses/by-nc-nd/4.0/> CC BY-NC-ND 4.0.</a> | Marine mammals in the Barents Sea region have among the highest levels of contaminants recorded in the Arctic and the Atlantic walrus (<i>Odobenus rosmarus rosmarus</i>) is one of the most contaminated species within this region. We therefore investigated the relationships bewteen blubber concentrations of lipophilic persistent organic pollutants (POPs) and plasma concentrations of perfluoroalkyl substances (PFASs) and markers of endocrine and immune functions in adult male Atlantic walruses (n = 38) from Svalbard, Norway. To do so, we assessed plasma concentrations of five forms of thyroid hormones and transcript levels of genes related to the endocrine and immune systems as endpoints; transcript levels of seven genes in blubber and 23 genes in blood cells were studied. Results indicated that plasma total thyroxine (TT4) concentrations decreased with increasing blubber concentrations of lipophilic POPs. Blood cell transcript levels of genes involved in the function of T and B cells (FC like receptors 2 and 5, cytotoxic T-lymphocyte associated protein 4 and protein tyrosine phosphatase non-receptor type 22) were increased with plasma PFAS concentrations. These results suggest that changes in thyroid and immune systems in adult male walruses are linked to current levels of contaminant exposure.
Показать больше [+] Меньше [-]Indoor PM2.5 in an urban zone with heavy wood smoke pollution: The case of Temuco, Chile Полный текст
2018
Jorquera, Héctor | Barraza, Francisco | Heyer, Johanna | Valdivia, Gonzalo | Schiappacasse Poyanco, Luis | Montoya, Lupita D.
Indoor PM2.5 in an urban zone with heavy wood smoke pollution: The case of Temuco, Chile Полный текст
2018
Jorquera, Héctor | Barraza, Francisco | Heyer, Johanna | Valdivia, Gonzalo | Schiappacasse Poyanco, Luis | Montoya, Lupita D.
Temuco is a mid-size city representative of severe wood smoke pollution in southern Chile; however, little is known about the indoor air quality in this region. A field measurement campaign at 63 households in the Temuco urban area was conducted in winter 2014 and is reported here. In this study, indoor and outdoor (24-hr) PM2.5 and its elemental composition were measured and compared. Infiltration parameters and outdoor/indoor contributions to indoor PM2.5 were also determined. A statistical evaluation of how various air quality interventions and household features influence indoor PM2.5 was also performed. This study determined median indoor and outdoor PM2.5 concentrations of 44.4 and 41.8 μg/m3, respectively. An average infiltration factor (0.62 ± 0.06) was estimated using sulfur as a tracer species. Using a simple mass balance approach, median indoor and outdoor contributions to indoor PM2.5 concentrations were then estimated as 12.5 and 26.5 μg/m3, respectively; therefore, 68% of indoor PM2.5 comes from outdoor infiltration. This high percentage is due to high outdoor pollution and relatively high household air exchange rates (median: 1.06 h−1). This study found that S, Br and Rb were dominated by outdoor contributions, while Si, Ca, Ti, Fe and As originated from indoor sources. Using continuous indoor and outdoor PM2.5 measurements, a median indoor source strength of 75 μg PM2.5/min was estimated for the diurnal period, similar to literature results. For the evening period, the median estimate rose to 135 μg PM2.5/min, reflecting a more intense wood burning associated to cooking and space heating at night. Statistical test results (at the 90% confidence level) support the ongoing woodstove replacement program (reducing emissions) and household weatherization subsidies (reducing heating demand) for improving indoor air quality in southern Chile, and suggest that a cookstove improvement program might be helpful as well. In the city of Temuco, southern Chile, 68% of indoor PM2.5 comes from severe outdoor pollution due to intensive wood burning, enhanced by poor household building standards and fuel poverty
Показать больше [+] Меньше [-]Indoor PM2.5 in an urban zone with heavy wood smoke pollution: The case of Temuco, Chile Полный текст
2018
Jorquera, Héctor | Barraza, Francisco | Heyer, Johanna | Valdivia, Gonzalo | Schiappacasse, Luis N. | Montoya, Lupita D.
Temuco is a mid-size city representative of severe wood smoke pollution in southern Chile; however, little is known about the indoor air quality in this region. A field measurement campaign at 63 households in the Temuco urban area was conducted in winter 2014 and is reported here. In this study, indoor and outdoor (24-hr) PM2.5 and its elemental composition were measured and compared. Infiltration parameters and outdoor/indoor contributions to indoor PM2.5 were also determined. A statistical evaluation of how various air quality interventions and household features influence indoor PM2.5 was also performed.This study determined median indoor and outdoor PM2.5 concentrations of 44.4 and 41.8 μg/m3, respectively. An average infiltration factor (0.62 ± 0.06) was estimated using sulfur as a tracer species. Using a simple mass balance approach, median indoor and outdoor contributions to indoor PM2.5 concentrations were then estimated as 12.5 and 26.5 μg/m3, respectively; therefore, 68% of indoor PM2.5 comes from outdoor infiltration. This high percentage is due to high outdoor pollution and relatively high household air exchange rates (median: 1.06 h−1).This study found that S, Br and Rb were dominated by outdoor contributions, while Si, Ca, Ti, Fe and As originated from indoor sources. Using continuous indoor and outdoor PM2.5 measurements, a median indoor source strength of 75 μg PM2.5/min was estimated for the diurnal period, similar to literature results. For the evening period, the median estimate rose to 135 μg PM2.5/min, reflecting a more intense wood burning associated to cooking and space heating at night.Statistical test results (at the 90% confidence level) support the ongoing woodstove replacement program (reducing emissions) and household weatherization subsidies (reducing heating demand) for improving indoor air quality in southern Chile, and suggest that a cookstove improvement program might be helpful as well.
Показать больше [+] Меньше [-]Development of a flux DMT with integrated adsorptive stripping voltammetry for free metal ions detection in solution Полный текст
2018
Janot, Noemie | Rotureau, Elise | Pinheiro, Jose Paulo
Development of a flux DMT with integrated adsorptive stripping voltammetry for free metal ions detection in solution. Interfaces Against Pollution
Показать больше [+] Меньше [-]Solid-solution partitioning of Rare Earth Elements in mine-tailings and soils in China: experimental results and multi-surface modelling Полный текст
2018
Janot, Noemie | Huot, Hermine | Otero-Fariña, Alba | Leguédois, Sophie | Groenenberg, Jan E.
Solid-solution partitioning of Rare Earth Elements in mine-tailings and soils in China: experimental results and multi-surface modelling. Interfaces Against Pollution
Показать больше [+] Меньше [-]Assessing agricultural soil pollution risks from organic waste recycling: informing regional participatory waste management Полный текст
2018
Wassenaar, Tom | Feder, Frédéric | Doelsch, Emmanuel
The well-informed recycling of organic waste to agricultural land becomes increasingly desirable in dynamic, developing regions worldwide. Pursuing locally optimal benefit-risk ratios, agro-environmental research in support of OW recycling does not focus on avoiding contamination perse, but on the control of dynamics, in soil and other environmental compartments, in order not to exceed risk thresholds. We present a series of empirical research efforts that inform decision making in regions under OW pressure on OW-contained trace contaminant fate under local conditions. Their results illustrate that the present understanding of trace elements fate allows for the ex-ante assessment of fate under specific use scenarios and local conditions, with a limited set of simplifications. A well-established set of analytical tools provides the information required by such assessments. Understanding of OW-borne organic contaminants is less advanced, but the present capacity to project fate under local conditions does allow for the approximate appreciation of risk levels, the major benefit of which is to focus subsequent research on substances of concern. Ongoing long-term field trials may critically advance our understanding of OW-borne contaminant fate in soil. Developing a reasonable capacity to assess biological contaminant fate is one of its priorities.
Показать больше [+] Меньше [-]Long term organochlorine soil pollution in agriculture: The lessons learnt from the Chlordecone pollution in French West Indies Полный текст
2018
Lesueur Jannoyer, Magalie | Cattan, Philippe | Mottes, Charles | Clostre, Florence | Della Rossa, Pauline | Woignier, Thierry
The French West Indies face nowadays a diffuse and long term environmental pollution related to historical use of organochlorine insecticide in banana fields, Chlordecone (CLD). Due to its stability, it now pollutes soil, waters, agricultural products and leads to a global exposure of people and ecosystems. We wonder how to manage such a complex pollution system involving all environmental compartments, linked each other. For that, we have been conducting research studies for more than 15 years in the field of agronomy and environment to explore the fate of the molecule in the environment, the impact on food safety, and also the remediation options. Three main points are addressed: i) how to characterize the pollution and to make easier the diagnosis? ii) how to assess the impacts on environmental compartments and agricultural products? iii) How to manage the pollution? The tools we developed make a diagnosis of such pollution easier at different scales (field, farm, watershed, and territory). We built monitoring support systems for the water quality of rivers with models helping to understand variability of water contamination. We built also decision support systems to farmers to manage their soil pollution and choose the crops that will ensure food security. Now CLD content of local crop products on the market complies with the Maximum Residue Limit. Management is more complex for animal products, and further investigations are needed. We investigated alternative solution to enhance CLD soil sequestration, using physical properties of French West Indies volcanic soil and organic matter amendment. Increased organic matter content in soil reduced drastically the CLD transfer from soil to water, but this effect was not perennial and amendment had to be regularly applied. Our results show that an integrative approach is needed to build efficient policies to manage such pollution than to prevent new ones.
Показать больше [+] Меньше [-]Resiliency of a healthy fish stock to recruitment losses from oil spills Полный текст
2018
Carroll, JoLynn | Vikebø, Frode Bendiksen | Howell, Daniel | Broch, Ole Jacob | Nepstad, Raymond | Augustine, Starrlight | Skeie, Geir Morten | Bast, Radovan
We simulate oil spills of 1500 and 4500 m3/day lasting 14, 45, and 90 days in the spawning grounds of the commercial fish species, Northeast Arctic cod. Modeling the life history of individual fish eggs and larvae, we predict deviations from the historical pattern of recruitment to the adult population due to toxic oil exposures. Reductions in survival for pelagic stages of cod were 0-10%, up to a maximum of 43%. These reductions resulted in a decrease in adult cod biomass of <3% for most scenarios, up to a maximum of 12%. In all simulations, the adult population remained at full reproductive potential with a sufficient number of juveniles surviving to replenish the population. The diverse age distribution helps protect the adult cod population from reductions in a single year's recruitment after a major oil spill. These results provide insights to assist in managing oil spill impacts on fisheries. | publishedVersion
Показать больше [+] Меньше [-]Solid-solution partitioning of Rare Earth Elements in mine-tailings and soils in China: experimental results and multi-surface modelling Полный текст
2018
Janot, Noemie | Huot, Hermine | Otero-Fariña, Alba | Leguédois, Sophie | Groenenberg, Jan E. | Laboratoire Sols et Environnement (LSE) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS) | Centre National de la Recherche Scientifique (CNRS) | Sun Yat-sen University [Guangzhou] (SYSU) | Wageningen University and Research [Wageningen] (WUR)
International audience | Solid-solution partitioning of Rare Earth Elements in mine-tailings and soils in China: experimental results and multi-surface modelling. Interfaces Against Pollution
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