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Ranc B.,CNRS Interdisciplinary Laboratory for Continental Environments | Ranc B.,CNRS Reactions and Process Engineering Laboratory | Faure P.,CNRS Interdisciplinary Laboratory for Continental Environments | Croze V.,ICF Environnement | Simonnot M.O.,CNRS Reactions and Process Engineering Laboratory
Journal of Hazardous Materials

In situ chemical oxidation (ISCO) is a promising alternative to thermal desorption for the remediation of soils contaminated with organic compounds such as polycyclic aromatic hydrocarbons (PAHs). For field application, one major issue is the selection of the optimal doses of the oxidizing solution, i.e. the oxidant and appropriate catalysts and/or additives. Despite an extensive scientific literature on ISCO, this choice is very difficult because many parameters differ from one study to another. The present review identifies the critical factors that must be taken into account to enable comparison of these various contributions. For example, spiked soils and aged, polluted soils cannot be compared; PAHs freshly spiked into a soil are fully available for degradation unlike a complex mixture of pollutants trapped in a soil for many years. Another notable example is the high diversity of oxidation conditions employed during batch experiments, although these affect the representativeness of the system. Finally, in this review a methodology is also proposed based on a combination of the stoichiometric oxidant demand of the organic pollutants and the design of experiments (DOE) in order to allow a better comparison of the various studies so far reported. © 2016 Elsevier B.V. Source

Chen Zee E.,University Pierre and Marie Curie | Cornet P.,University Pierre and Marie Curie | Lazimi G.,University Pierre and Marie Curie | Rondet C.,University Pierre and Marie Curie | And 4 more authors.
Gynecologie Obstetrique Fertilite

Background Endocrine disruptors are ubiquitous chemicals contaminants in the environment, wildlife, and humans. Their adverse effects on reproduction are well-documented. There is growing evidence that they can contribute to the current emergence of chronic diseases. Objectives Our aim is to assess the relationships between endocrine disruptors and the neonatal health outcomes. Methods Two persons have independently reviewed Medline and Toxline databases about the following pollutants: bisphenol A, phthalates, parabens, brominated flame retardants and perfluorinated compounds. Only the human epidemiological studies, in general population with an abstract available, published between 2007 January the 1st and 2011 December the 31st, were analysed. The quality of each study was assessed with the Strobe score. Results Twenty-five out of 680 studies were included in the analysis. All pollutants were widely detected in maternal and new borns samples. Most of the studies have shown associations between bisphenol A, brominated flame retardants and perfluorinated compounds and lower birth weight. The effects on gestational age were less documented and have shown no clear connection. Results for phthalates were more ambiguous. Only one non-instructive study was found on parabens. Discussion Due to the inherent methological bias on endocrine disruptors research, further additional studies on environmental health must be investigated. It seems necessary to adopt preventive health measures first for vulnerable population. © 2013 Elsevier Masson SAS. All rights reserved. Source

Ponsin V.,Aix - Marseille University | Ponsin V.,French Environment and Energy Management Agency | Coulomb B.,Aix - Marseille University | Guelorget Y.,ICF Environnement | And 2 more authors.
Journal of Contaminant Hydrology

The main aim of this study was to explore the feasibility of source zone bioremediation by nitrate and nutrient injection in a crude-oil contaminated aquifer using a recirculating well dipole. Groundwater pumped from a downgradient well at a rate of 2.5 m3 h-1 was enriched with bromide (tracer), nitrate and ammonium phosphate and injected in a well 40 m upgradient. The test was run for 49 days with solute injection, followed by 65 days of dipole operation without solute addition. The resulting bromide breakthrough curve allowed quantifying a first-order leakage coefficient of 0.017 day-1 from the dipole, whereas from the nitrate data a first-order nitrate consumption rate of 0.075 day-1 was determined. Dissolved hydrocarbon concentrations including benzene decreased to non-detect in 84 days but experienced important rebounds after ending circulation. Nitrite accumulated temporarily but was consumed entirely when solute injection stopped. The mass balance calculations revealed that about 83% of the nitrate was used for hydrocarbon degradation, with the remaining being used for oxidation of reduced sulfur. A reactive transport model was used for the delineation of the treated zone. This model suggested that denitrification influenced flow and transport in the dipole. It is concluded that successful promotion of denitrifying hydrocarbon degradation is easily obtained in this aquifer and enables to abate dissolved concentrations, and that dipole configuration is a good option. © 2014 Elsevier B.V. All rights reserved. Source

Ponsin V.,ICF Environnement | Guelorget Y.,ICF Environnement
Eau, l'INDUSTRIE, les Nuisances

The rupture of a pipeline in the La Crau plain on August 7th 2009 was an accident unique in Europe by the volumes spilled and by its location at the heart of a nature resen,e. Two years after this event, it appears appropriate to present an initial experience feedback on this accident that was one of the triggering events in the changes to the industria' equipment safety act (order of December 20th 2010). Source

Lemaire J.,University of Lorraine | Croze V.,ICF Environnement | Maier J.,ICF Environnement | Simonnot M.-O.,University of Lorraine

An industrial coating site in activity located on a chalky plateau, contaminated by BTEX (mainly xylenes, no benzene), is currently remediated by in situ chemical oxidation (ISCO). We present the bench scale study that was conducted to select the most appropriate oxidant. Ozone and catalyzed hydrogen peroxide (Fenton's reaction) were discarded since they were incompatible with plant activity. Permanganate, activated percarbonate and activated persulfate were tested. Batch experiments were run with groundwater and groundwater-chalk slurries with these three oxidants. Total BTEX degradation in groundwater was reached with all the oxidants. The molar ratios [oxidant]:[Fe 2+]:[BTEX] were 100:0:1 with permanganate, 100:100:1 with persulfate and 25:100:1 with percarbonate. Precipitation of either manganese dioxide or iron carbonate (siderite) occurred. The best results with chalk slurries were obtained with permanganate at the molar ratio 110:0:1 and activated persulfate at the molar ratio 110:110:1. To avoid precipitation, persulfate was also used without activation at the molar ratio 140:1. Natural Oxidant Demand measured with both oxidants was lower than 5% of initial oxidant contents. Activated percarbonate was not appropriate because of radical scavenging by carbonated media. Permanganate and persulfate were both effective at oxidant concentrations of ca 1gkg -1 with permanganate and 1.8gkg -1 with persulfate and adapted to site conditions. Activation of persulfate was not mandatory. This bench scale study proved that ISCO remediation of a chalky aquifer contaminated by mainly xylenes was possible with permanganate and activated or unactivated persulfate. © 2011 Elsevier Ltd. Source

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