Tesi: "Soil pollutants"

1

Cousins, Ian T. "Air-soil exchange of persistent organic pollutants (POPs)." Thesis, Lancaster University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310506.

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2

Teng, Xu, Zhang Wen-hua, and Shi Bi. "Characteristics of typical pollutants in tannery site soil - 75." Verein für Gerberei-Chemie und -Technik e. V, 2019. https://slub.qucosa.de/id/qucosa%3A34271.

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Content: This paper briefly introduced the process of leather manufacture and the potential pollution sources of soil in tannery sites. Pollutants are mainly derived from the use of a large number of various chemicals and organic matter decomposed by raw skin. The characteristics of typical pollutants in tannery sites soil were summarized, including tannery site soil pH, organic and inorganic compounds, and heavy metals, etc., especially the status of chromium contamination were reviewed. The pH of soil in the tanning workshop (6.65-7.8) is generally lower than tannery sludge dumping site (7.94-8.40). The main organic pollutants contained in the tannery site soil include nitrogen compound, grease, petroleum hydrocarbon. In tannery sludge dumping site soil, the content of nitrogen compound (10cm depth) is 28400 mg/kg, which is similar to tannery sludge. The content of petroleum hydrocarbon is 5-700 mg/kg, which partially exceed the limits of China agricultural land quality standard(<500 mg/kg). In tanning workshop soil, the content of grease is 220-62000 mg/kg. The main inorganic pollutants contained in the tannery site soil include sulfide, high concentration of salt, lime. The high salt content of tannery sludge (99000 mg/kg) leads to high salt content in soil (5500-17500 mg/kg). Total hardness (>450mg/L), total dissolved solids (>1000mg/L), sulfate ions (>250mg/L), nitrite nitrogen (>0.02mg/L) partially exceed the limits of China groundwater quality standard, which are found in groundwater below the tannery site. Heavy metal pollutants in the tannery sites soil have many characteristics and large differences in content, due to the different tanning processes. Among them, chromium (Cr) is the most used heavy metal and the highest content of pollutants. Cr content in tanning process wastewater, dyeing process wastewater and chromiumcontaining sludge are about 2000-3000 mg/L, 30-40 mg/L and 8500-25800 mg/kg, respectively. Total Cr content in the partial tannery sites soil are higher than 800 mg/kg, which exceed the limits of China agricultural land quality standard(<150mg/kg). Surprisingly, Cr(VI) appears in tannery sites soil and the contents are partly higher than 40 mg/kg, which exceed the limits of China development land quality standard(<3.0mg/kg). Furthermore, the more effort needs to be directed toward the chemistry of chromium-organic complex pollutants, and an understanding of the speciation of Cr in highly organics contaminated tannery site soil is essential for the development of suitable remediation strategies for contaminated soil. Take-Away: 1. The pH of soil in the tanning workshop (6.65-7.8) is generally lower than tannery sludge dumping site(7.94-8.40). 2. Total Cr content in the partial tannery sites soil are higher than 800 mg/kg, which exceed the limits of China agricultural land quality standard(<150mg/kg). 3. Cr(VI) appears in tannery sites soil and the contents are partly higher than 40 mg/kg, which exceed the limits of China development land quality standard(<3.0mg/kg).

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3

Lafontaine, Marc Carleton University Dissertation Chemistry. "Supercritical fluid extraction of priority pollutants from soil matrices." Ottawa, 1993.

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4

Mwepu, Mireille K. M. "Attenuation of ionic pollutants in selected South African soils." Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/2516.

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Thesis (MScAgric (Soil Science))--University of Stellenbosch, 2007. Two–thirds of South Africa, including more than 280 towns and settlements are largely dependent on groundwater for their drinking water supply and development. However, groundwater resources in South Africa are limited both in terms of quantity and quality, especially in the semi–arid parts of the country (Sililo et al., 2001, p. i). Therefore, the importance of protecting groundwater resources from pollution has been recognized. The first objective of this research was to investigate the attenuation capacity of a selection of soil horizons and materials representing major types of diagnostic horizons and materials in the South African soil classification in order to validate their chemical attenuation ratings as provisionally specified by Sililo et al. (2001, p. 4.6). The second objective was to assess the pollutant attenuation capacity of South African soil horizons and materials as well as describe the diagnostic value of key chemical properties of soils for conveying information on their contaminant transport/attenuation potential. The third objective was to investigate whether it is possible to apply acid/base priming using H2SO4 and Ca(OH)2 to a bulk quantity of soil in order to reduce the mobility of contaminants.

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5

Kurt-Karakus, Perihan Binnur. "Persistent organic pollutants and soils : studies on their distribution, air-soil exchange and degradation." Thesis, Lancaster University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440375.

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6

Juck, David F. "Polyphasic examination of microbial communities in soils contaminated with organic pollutants." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38209.

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A polyphasic approach was used to examine the impact of contamination on soil microbial community structure. Two systems were examined using a combined biochemical and molecular biological approach. Petroleum hydrocarbon contaminated soils from two Northern Canadian sites, representing long-term contamination, were examined using Biolog GN plates and PCR-denaturing gradient gel electrophoresis (DGGE) analysis of total community 16S rDNA. Results obtained using both methods demonstrated a positive correlation between samples that was based on the geographical origin of the samples, not on contamination level. In the second system, non-contaminated soil was contaminated with the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) to monitor the effect of short- to medium-term contamination. Changes in the soil microbial community were examined using PCR-DGGE of total community 16S rDNA combined with RDX mineralization and chemical analysis of intermediates. The non-contaminated loam soil had an inherent RDX degradative capability and contamination of soil columns with 1000 mg RDX/kg soil did not significantly change the 16S rDNA bacterial community profile. The bacterial diversity remained high as estimated by the number of bands present in the DGGE and by NQ-78704 statistical rarefaction analysis of 16S rDNA clone RFLPs. The same soil, used in 10% soil slurries (w/v), demonstrated two apparently different RDX degradation mechanisms based on mineralization and chemical analysis. The differences were based on aerobic versus anaerobic conditions and the presence/absence of Na3 citrate. PCR-DGGE performed on 16S rDNA from aerobic slurries amended with Na3-citrate detected the stimulation of 3 operational taxonomic units, identified as Stenotrophomonas sp., Sphingomonas sp. and a member of the Alcaligenaceae. The results from the two systems examined (short- to medium-term and long-term contamination) demonstrated the utility of a polyphasic approach in the examina

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7

Mwepu, Mireille K. M. "Mobility of ionic pollutants in selected South African soils /." Link to the online version, 2007. http://hdl.handle.net/10019/370.

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8

Tiensing, Tinnakorn. "Novel techniques in assessing bioavailability of pollutants in soils." Thesis, University of Aberdeen, 2002. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU153957.

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Effective techniques for assessing soil environmental pollution are required to develop protective policy. Chemical methods have been traditionally used to determine total concentration of pollutants and biologically linked measurements have been used to assess the bioavailable fraction of pollutants. Bioluminescence-based microbial bioassays have been shown to respond to the bioavailable fractions. Growth and bioluminescence of lux-marked E. coli HB101 and P. fluorescens 10586r were characterised and optimised for freeze-drying culture. Freeze-drying cultures have been used effectively because of their ease of use, rapid assay response and sensitivity to a wide range of pollutants. An assessment of Zn and Cd amended soil was investigated. Two different techniques (centrifugation and Rhizon sampler) were used to obtain the interstitial pore water of soils. The concentrations of Zn and Cd were significantly higher in the soil solution extracted using the centrifugation technique compared to the Rhizon sampler technique. The biosensors responded to the free metal concentrations in the soil solution. An assessment of the toxicity of 2,4-dichlorophenol, 2,4,6-trichlorophenol and pentachlorophenol, individually and in combinations, was tested in deionised water (pH 5.5), soil solutions, and soils using lux-marked E. coli HB101 and P. fluorescens 10586r. Toxicity interaction responses of the mixture chlorophenols were predicted using a model. Synergistic interactions were observed for the response of P. fluorescens 10586r pUCD60-7 to all combinations of chlorophenol tested, while the response of E. coli HB101 pUCD607 varied with the matrix solutions tested. Bioavailability of naphthalene was studied using cyclodextrin-based extractions caused to the luminescence response of Pseudomonas fluorescens KH44 pUTK21. Increasing the concentrations of beta-cyclodextrin (b-CD) and hydroxylpropyl-b-cyclodextrin (HPBC) in the extract solutions increased the apparent concentration of naphthalene in the soil solutions. The luminescence response of P. fluorescens HK44 was associated with bioavailable of naphthalene.

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9

Mashreghi, Mansour. "Survival and activity of genetically engineered degradative inocula in soil." Thesis, University of Aberdeen, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302452.

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In this study bioluminescence-marker systems were used to investigate the fate of two genetically engineered degradative bacteria in soil under different conditions. These bacteria were chromosomally lux-marked Alcaligenes eutrophus H850 Lr with luxAB genes which was able to degrade polychlorinated biphenyls (PCBs), and Pseudomonas stutzeri P16. P. stutzeri P16 was genetically marked with the luxAB tet cassette by insertional mutagenesis using mini Tn5-transposons and was characterised for lux gene stability, phenanthrene degradability and sensitivity to aldehyde. Insertion of lux gene into genome of P. stutzeri P16 provided a novel strain with lower maximum specific growth rate and less sensitivity to high concentrations of phenanthrene in liquid culture. Survival and activity of P. stutzeri P16 luxAB4 was further investigated in soil amended with low and high concentrations of phenanthrene. Initially high concentrations of phenanthrene had a less toxic effect on viable cell concentrations and luminescence activity of genetically engineered P. stutzeri P16 comparing with its wild type showing that lux-marking the above degradative strain made the marked strain more suitable for environmental application in heavily polluted sites. However, resistant cells to high concentration of phenanthrene were not able to survive longer than those which was inoculated to microcosms with lower concentrations of phenanthrene. This indicates that toxicity of the target compound and its concentration have to be considered before releasing the GEMs. Degradation of phenanthrene was enhanced in both sterile and non-sterile soil inoculated with P. stutzeri P16 luxAB4. This study could be used as model for further investigated of degradation of other PAHs such as fluoranthene, benz[a]anthracene, benzo[a]pyrene, by degradative bacteria and also monitoring the survival and activity of those bacteria in the environment using bioluminescence-marker systems.

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10

Eastling, Paul Michael. "Polychlorinated biphenyls in Cedar Rapids soil." Thesis, University of Iowa, 2010. https://ir.uiowa.edu/etd/492.

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Extreme flooding of rivers may contribute to increased loading of persistent organic pollutants (POPs) to the Great Lakes, the Mississippi river, and other large lakes and surface waters downstream of industrial and urban areas. This study examines the fate of POPs that were mobilized during heavy flooding of the Cedar River and the small urban city of Cedar Rapids, Iowa during the summer of 2008. This study focuses polychlorinated biphenyls (PCBs). We hypothesize that these PCBs were mobilized by the flood water and that residues remained in the soils and sediments of the residential areas of the city. To test our hypothesis, soil samples were collected from ~200 of residential locations in the downtown Cedar Rapids area and analyzed for the three compound groups. Samples were extracted using an accelerated solvent extraction (ASE 300), and analyzed using GC/ECD, GC/MSD and GC/MS/MS.

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11

Hrapovic, L. "Laboratory study of intrinsic degradation of organic pollutants in compacted clayey soil." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ58216.pdf.

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12

Persson, Ylva. "Chlorinated organic pollutants in soil and groundwater at chlorophenol-contaminated sawmill sites." Doctoral thesis, Umeå : Department of Chemistry, Umeå University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-989.

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13

Eriksson, Johan. "Retention and mobilisation of trinitrotoluene, aniline, nitrobenzene and toluene by soil organic matter /." Umeå : Dept. of Forest Ecology, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/s266.pdf.

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14

Howsam, Mike. "The role of woodlands in the cycling of polycyclic aromatic hydrocarbons (PAHs) in the environment." Thesis, Lancaster University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310455.

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15

Magoha, Happy Steven. "Destruction of polycyclic aromatic hydrocarbons (PAH's) and aliphatic hydrocarbons in soil using ball milling thesis submitted in (partial) fulfilment of the Master of Applied Science, Auckland University of Technology, May 2004." Full thesis. Abstract, 2004. http://puka2.aut.ac.nz/ait/theses/MagohaH.pdf.

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16

Eigenhuis, Bernhard. "Developing the soil pollution potential as an environmental management cost estimation index for washing inorganic pollutants from soils / B. Eigenhuis." Thesis, North-West University, 2004. http://hdl.handle.net/10394/283.

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This study investigated the concept of the Soil Pollution Potential (SPP), a concept analogous to the Global Warming Potential used to compare various chemicals during Life Cycle Analysis of industrial projects. The objective of the study was to identify a reference soil pollution scenario and a reference inorganic soil pollutant that provide the basis for calculating Soil Pollution Potentials for a wide range of soil pollution scenarios. The reference inorganic soil pollutant has been identified as Aluminium and a reference soil pollution scenario is also described in this dissertation, proving the hypothesis that such a reference pollutant could be identified through the use of statistical analysis of resulting modelling data for a wide range of parameter values. The reference pollutant was identified through a statistical evaluation of the model simulation time required to simulate the remediation of the soil profile. It was found that lower diffusion coefficients resulted in more time required, effectively limiting mass transfer in the soil profile. A regression equation was developed that simplifies the calculation of SPP values, reducing the need for complex numerical modelling. The regression equation describes approximately 96% of the variation found in the modelling data and is considered sufficiently accurate. A simpler form of the regression equation was also derived exhibiting a R2 of approximately 0.87. This dissertation also provides a simple equation to calculate the volume of flushing water required to remediate polluted soil profiles in other soil pollution scenarios within the parameter value ranges identified in this study. It is possible to repeat this study, but focussing on organic pollutants in the soil profile. Azelate has been identified as a possible candidate reference organic pollutant based on a similar diffusion coefficient in water as compared to that of Aluminium. A similar approach has been followed by ICI using Environmental Quality Standards and toxicity characteristics of Copper and Formaldehyde in the aquatic environment to select inorganic and organic reference chemicals. Such an organic reference will provide an important link in the SPP continuum and should be further investigated. This study has clearly and conceptually illustrated how the SPP can be used as an environmental management cost estimation index for different soil washing (flushing) scenarios. A generic equation for relative cost (cost index) was derived. Finally, SPP values were found to range from 9.81E-06 to 9.67 for the parameter values in this study, with an associated water cost ranging from R0.00 to R145.00 per m3 at an assumed cost of R3.00 per m3. Published soil flushing cost (water and operation of equipment) was found to range from R140.00 to R1400.00 per m3 of soil (year 2004); it appears less expensive than the published cost of soil washing. Furthermore does it appears that the cost of water accounts for approximately 10% of the published cost of soil flushing, but further investigation is required in future to confirm this. Thesis (Ph.D. (Geography and Environmental Studies))--North-West University, Potchefstroom Campus, 2004.

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17

Liu, Fuzhen. "Remediation of soil contaminated by organic pollutants using Tween 80 and electrochemical advanced oxidation processes." Thesis, Paris Est, 2020. http://www.theses.fr/2020PESC2055.

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Sous la direction du professeur Mehmet Oturan et du professeur Hui Zhang, j’ai fini toutes les parties des thèses. Un article a été publié dans SCI et les autres parties sont prêtes à se soumettre à la revue. Maintenant, je modifie les papiers et les thèses. Les difficultés sont la détection des contaminants parce qu’il a besoin de la machine de fluorescence et de la méthode d’extraction complexe Soil contaminated by petroleum-hydrocarbons is a serious environmental problem since it is toxic to agriculture and human. And the polycyclic aromatic hydrocarbons (PAHs) in petroleum-hydrocarbons possess carcinogenicity, teratogenicity, mutagenicity, low volatility and poor solubility properties. Moreover, PAHs are persistent in soil and difficult to be degraded. Hence, effective methods are essential to remedy soil contaminated by petroleum-hydrocarbons and particularly the PAHs. Among various remediation methods, soil washing (SW) combined with surfactant is a promising techniques since it is an economical and effective approach. This technology promotes the transformation of contaminants from soil to aqueous solution, which is especially applied for heavily contaminated soil. However, a soil washing solution highly loaded with surfactant and contaminants is produced. Therefore, effective treatment of soil washing solution is a challenge for promoting the application of surfactants and the remediation of contaminated soil. The combination of soil washing process and electrochemical advanced oxidation processes (EAOPs) constitutes an effective technique for the treatment of soil washing solution. In this paper, Tween 80 was applied as surfactant during soil washing process. The lipophilic part of Tween 80 tends to contaminants or soil particles and the hydrophilic part has tendency to the aqueous phase. Thus, Tween 80 promotes the transformation of hydrophobic organic contaminants from soil to aqueous phase. Then the soil washing solution highly loaded with contaminants and surfactant was treated by EAOPs, processes based on the generation of strong oxidant species such as hydroxyl radicals (•OH), sulfate radicals (SO4•−) and active chlorine (•Cl), are one of the most efficient methods for degrading refractory organic pollutants in soil washing solution. The effect of EAOPs including electro-oxidation (EO), electro-Fenton (EF), sulfate radical-based advanced oxidation processes (AOPs) was investigated in the degradation of petroleum-hydrocarbons. Besides, a potential advanced oxidation process including the presence of chlorine s was applied for treating soil washing solution which contains polycyclic aromatic hydrocarbons (PAHs) and Tween 80

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18

Meijer, Sandra N. "The role of air-soil exchange in the global transport and distribution of persistent organic pollutants." Thesis, Lancaster University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404221.

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19

Yao, ZhengXin. "Natural Metal/Oxides for Catalytic Oxidation of Persistent Organic Pollutants (POPs) in Contaminated Water and Soil." Thesis, Curtin University, 2021. http://hdl.handle.net/20.500.11937/88252.

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This study proposed an effective strategy by utilizing natural minerals consisting of transition metal elements as the substitute for conventional synthetic catalysts in PMS activation to decompose organic pollutants in situ, which enables the manufactory to markedly reduce the processing cost, contributing to the industrial application of natural minerals in environment remediation technology.

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20

Ahmad, Faheem. "Numerical modelling of transport of pollutant through soils." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08182009-040239/.

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21

Forsberg, Sverker. "Behaviour of ¹³⁷Cs and ⁹⁰Sr in agricultural soils : influence of ageing and soil type on availability, migration and plant uptake /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2000. http://epsilon.slu.se/avh/2000/91-576-5735-1.pdf.

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22

Taylor, Tammy Palmer. "Characterization and surfactant enhanced remediation of organic contaminants in saturated porous media." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/19899.

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23

Wang, Jian Chyun. "A study of contaminant transport in porous media." Thesis, The University of Sydney, 1997. https://hdl.handle.net/2123/27630.

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The contamination of the environment from waste disposal activities and industry is of great concern to engineers. Also of interest are ways of preventing the further spreading of contaminants by the use of well-designed disposal facilities and methods for rehabilitating existing contaminated areas. It is the objective of this thesis to develop a computationally efficient numerical technique and to carry out experimental work in order to investigate contaminant migration in porous or fractured media such as soil and rock.

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24

龍銀花 and Yinhua Long. "Determination of organic pollutants in air and soil by supercritical fluid extraction, capillary electrophoresis, chromatographic andelectrochemical methods." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31242108.

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25

Quinn, Laura Penelope. "Persistent organic pollutants (POPs) in soil associated with an active incinerator in Potchefstroom, South Africa / L.P. Quinn." Thesis, North-West University, 2005. http://hdl.handle.net/10394/1013.

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POPs are a group of chemicals that have been extensively studied over the last few years. The main reason that these chemicals have received so much scientific attention is the myriad of negative effects they have on the environment and human health. The properties that cause the deleterious effects include a high molecular stability, rendering them highly persistent. Added to this is the lipophilic and hydrophobic nature of the compounds. POPs will thus tend to bio-accumulate and bio-magnify in the environment, causing a direct threat to humans and wildlife. To address this threat, the Stockholm Convention on Persistent Organic Pollutants, under the supervision of United Nations Environment programme (UNEP), was initiated and became legally binding on 17 May 2004. All countries, including South Africa, which ratified this agreement, will be expected to monitor and regulate the formation of POPs. Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) are all members of the dioxin-like family of POPs. This family of chemicals pose serious health threats such as carcinogenic effects and negative effects on reproduction. These substances, with the exception of PCBs, are formed unintentionally as by-products of industrial and thermal processes. One of the main sources of dioxin-like chemicals is medical waste incinerators. In this project the area surrounding a medical waste incinerator was monitored using a bio-assay technique. The determination of dioxin concentrations is usually preformed by chemical analysis, however, bio-assays have proven themselves to be a cheaper and time-saving screening method. The Toxic Equivalency Quotient (TEQs) determined through bio-assays can support chemical analysis in determining biologically-relevant risk assessments since bio-assay data has ecotoxicological relevance. These assays represent an integrated biological response to chemical pollutants, where biological effects are accounted for which is not possible in chemical analyses. One of the bio-assays used in the determination of the dioxin-like chemical TEQ is the H411 E reporter gene bio-assay. This assay is based on the Ah-receptor mediated toxicity of dioxin-like chemicals. Using this technique the TEQs for areas surrounding an active incinerator were determined, to indicate the distribution of these substances. The TEQs for the soil samples collected ranged between nondetectable and 154 ngTEQ/kg. There was no clear distributional pattern and the total organic carbon content in the soil did not seem to play a crucial role in the distribution of dioxin-like chemicals. Although a decrease in soil tillage showed a corresponding increase in TEQ. The predominant wind direction was taken into account but no correlation could be seen. However, meteorological parameters such as the ambient temperature and low precipitation in the area may have contributed to lower TEQ values. Cytotoxicity excluded data points and the phenomenon has to be addressed. High TEQ values in a residential area where free-range chickens are raised pose a serious concern to the level of dietary dioxin-like chemical intake. Eggs in the area could theoretically contain between 2.75 and 28.75 pgTEQ/g egg fat. Further studies are needed to determine how much dioxin-like chemicals are being transferred to humans through the consumption of free-range eggs Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2006.

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Long, Yinhua. "Determination of organic pollutants in air and soil by supercritical fluid extraction, capillary electrophoresis, chromatographic and electrochemical methods /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B23316834.

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27

Hollinger, Eric, of Western Sydney Hawkesbury University, and Faculty of Environmental Management and Agriculture. "Links between management of a market garden and stormwater losses of sediment, nitrogen and phosphorus." THESIS_FEMA_XXX_Hollinger_E.xml, 1998. http://handle.uws.edu.au:8081/1959.7/306.

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Market gardening is commonly characterised by intensive cultivation, high inputs of both organic and inorganic fertilisers, chemical over/misuse, frequent irrigation, and a low degree of soil cover. While market gardening is readily perceived to be detrimental to waterways, there is remarkably little data to quantify the impacts. Soil and nutrient loss in stormwater runoff varies with soil type, climate and production systems. Therefore local data are needed to determine the impact of market gardening on the Hawkesbury-Nepean. This should lead to a better understanding of how land management influences runoff quantity and quality so that practices can be improved. Objectives of this research were to : quantify sediment, N and P loss and assess the implications for waterways; relate sediment, N and P losses to specific land management practices and assess their impacts on profitability; and, reflect on this research in terms of extension and adoption of better land management. An 8.8 ha property with 6.6 ha of market garden was used as a case study in the Hawkesbury-Nepean Catchment. Soil samples were collected at the beginning and end of the study. Sediment core samples were collected from the drainage channel. A rainfall simulator was used to compare runoff volume from green manure and bare fallow beds. The research produced several recommendations for the extension and adoption of improved land management. In order to reduce sediment, N and P losses in stormwater, the primary focus should be on improving soil and nutrient management, in particular matching fertiliser inputs more closely to nutrient requirements. The secondary focus should be on utilising structural measures, in particular farm dams, to prevent pollutants from entering waterways. The outcome should be decreased costs to the farmer and decreased impacts on waterways. The use of N-fixing green manure to decrease the use of poultry manure should be explored. Master of Science (Hons)

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Schuster, Jasmin. "Temporal and spatial trends of persistent organic pollutants in air and soil : implications for their sources and environmental cycling." Thesis, Lancaster University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618816.

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Persistent organic pollutants (POPs) are defined by their characteristic properties in the environment, such as adverse effects on humans and other organisms, a low degradation rate, a potential for bioaccumulation and long range-transport. These properties are the reason that POPs are monitored in remote regions, like the Polar Regions and open oceans, even though they were mostly used in populated areas (urban or rural). A group of POPs was banned under the Stockholm Convention on Persistent Organic Pollutants in 2001 by a number of countries and more chemicals have been added to the list subsequently. To assess the effect of international regulation more information about the long-term fate of these chemicals, the transport processes and the exchange between different environmental media is needed. The first part of this thesis describes long-term trends of POPs such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in the environmental compartment air. One study discusses the trends that were observed with passive air samplers in remote locations along a transect across the UK and Norway. The air• concentrations monitored from 1994 to 2008 at 11 sites showed a general decline. While the total air concentrations decreased with increasing latitude, the decline rates did not differ between sampling sites. A second study discusses the trends of PCBs in the UK atmosphere for urban and rural sites. As in the remote areas, a steady decline was observed following first order kinetics. The PCB concentrations at each sampling site were directly proportional to the population density of the area. It was therefore concluded that air concentrations of PCBs are currently still defined by the direct input from primary source emissions and the observed decline mirrors a decline in emission. In order to assess the fate of POPs in other environmental media soil cores were collected following the transect for the passive air data across the UK and Norway. The soil cores were collected at identical locations ten years earlier. A direct comparison of the data between the sampling years proved that the decline in soil is more variable than in air for most monitored POPs. While there were nearly no changes in soil concentrations of organochlorine pesticides, there was a slight decline for PCBs and a strong decline for PBDEs. Changes in the burden, of PCBs per unit soil organic matter between 1998 and 2008 indicate the approach of soil-air equilibrium for the monitored sites. However chiral data and atmospheric data from the regions indicate that the influence of re-volatilization contributed only a minor component of the air burden of PCBs in remote areas of northern Europe. Important tools in monitoring regional and temporal trends of POPs are passive air samplers, which can be deployed at low cost in remote areas. A new type of sampling medium. the sorbent-impregnated polyurethane foam (SIP) disk, was assessed for its applicability for long-term monitoring of PCBs, PBDEs and hexachlorobenzene. Long-term deployment is a necessity for areas with low concentrations. In order to estimate the most precise atmospheric concentrations from the chemicals sequestered on the sampling medium, it would be preferable if the sampler and atmosphere are not in equilibrium and the sampled air volume is therefore directly proportional to the deployment time. It was found that the SIP disk presents a valid alternative to other established passive air sampling media. The last part of the thesis discusses a group of emerging POPs, the perfluorinated compounds (PFCs). PFCs were monitored in a passive air sampling campaign in different Asian countries. Differences were observed in the PFC composition at different sampling sites. These were explained with different usage pattern and regulations in the different countries. Further research is required to gain deeper understanding the transfer mechanism between different environmental compartments for POPs. The application of a model is needed to assess the increasing influence of secondary sources, i.e. revolatilisation from soils on atmospheric concentrations. While long-term studies for emerging compounds already exist, it is necessary to establish similar monitoring campaigns for emerging chemicals.

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29

Desborough, Jennifer L. "Exploring the utility of chiral signatures to further understanding of soil-to-herbage transfer of Persistent Organic Pollutants (POPs)." Thesis, University of Birmingham, 2012. http://etheses.bham.ac.uk//id/eprint/3537/.

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Chiral signatures were utilised as a means of determining the pathways of PCBs in the environment. Concentrations of HBCD diastereoisomers, enantiomers and degradation products were also determined in top soils from both the UK and Australia. Concentrations of PCBs 28/31, 52, 101, 118, 138, 153, and 180 and enantiomer fractions (EFs) of PCB 95 and 136 were determined in air, top soil and grass from an urban site in Birmingham, UK. Samples were taken approximately every 14 days at 5 graduating heights from the ground in summer 2009 (114 days) and spring 2010 (84 days). EFs of PCB 95 in air at 3cm height (average of 0.453 in 2009 and 0.468 in 2010), differed significantly (p<0.05) from the racemic EFs in air at 10, 40, 90, and 130 cm. The EFs of PCB 95 in soil were on average 0.452 in 2009 and 0.447 in 2010 and matched those in air at 3cm particularly in the 2009 campaign. Grass displayed an average EF of 0.468 (2009) and 0.484 (2010); values which were intermediate between those in soil and the racemic EFs in air measured at 10 cm and above. These data imply that at the study site, PCBs volatilise from soil to an extent discernible only at the soil:air interface, and that PCBs in grass arise due to foliar uptake of volatile emissions from soil. Atmospheric concentrations of PCBs increased significantly (p<0.05) with increasing height above the soil surface. This combined with the PCB 95 chiral signature data, suggests that the influence of PCB emissions from soil on airborne concentrations decreases with height while emissions from indoor air increases. HBCD chiral signatures were found to be racemic or near-racemic in all the air, grass and soil samples from the same urban site in Birmingham, UK used for sampling PCBs. Soils from 24 ii sites across the UK were also found to contain near racemic chiral signatures of HBCDs. This indicates that enantioselective microbial degradation is not occurring and the sites were unsuitable for a study like that used for PCBs to determine pathways of HBCDs into plants using chiral signatures. Concentrations of ΣHBCD from soils from the UK (n=24) were found to be 22 ng/g ranging between <0.03 to 420 ng/g. By comparison, the average concentration of ΣHBCD in soils from Australia (n=17) was 0.74 ng/g ranging between <0.0005 to 5.6 ng/g. Degradation products of HBCD, pentabromocyclododecenes (PBCDs) and tetrabromocyclododecadienes (TBCDs) were also semi-quantitatively determined in the soil samples. In the UK soils, PBCDs and TBCDs were determined in 7 and 6 of the soil samples respectively with concentrations ranging from 10-7300 pg/g for ΣPBCDs and 10-1300 pg/g for ΣTBCDs. In the Australian soils only TBCD was detected in soil at concentrations ranging from 2.3 to 450 pg/g ΣTBCDs. A preliminary environmental budget found soil to be the principal sink for HBCD in the UK.

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30

Lindeberg, Carola. "Long-term changes of mercury, lead and persistent organic pollutants in arctic environments." Doctoral thesis, Umeå : Department of Ecology and Environmental Science, Umeå Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1060.

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31

Larsson, Martin. "Quantifying macropore flow effects on nitrate and pesticide leaching in a structured clay soil : field experiments and modelling with the MACRO and SOILN models /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5489-1.pdf.

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32

Abu-Lail, Laila I. "An atomic force microscopy study of bacterial adhesion to natural organic matter-coated surfaces in the environment." Link to electronic thesis, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-050206-163823/.

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33

Yu, Xiezhi. "Assessment and bioremediation of solis contaminated by uncontrolled recycling of electronic-waste at Guiyu, SE China." HKBU Institutional Repository, 2008. http://repository.hkbu.edu.hk/etd_ra/876.

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34

Gardfors, Lars. "Föroreningsspridning via ledningsgravar : en fältstudie på Köpmanholmens industriområde." Thesis, Uppsala University, Department of Earth Sciences, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-88902.

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Sewer trenches usually contain material with a higher hydraulic conductivity then the adjacent soil. Thus they can serve as paths of preferential flow in a polluted area. Wastewater from factories can also leak from wastewater pipes and pollute the soil in the sewer trenches.The purpose of this project was to investigate pollutions in sewer trenches and in sewer pipes in the industrial area of Köpmanholmen, 20 km south of Örnsköldsvik in the north of Sweden. To make an estimation concerning the potential of transport of pollutions in sewer trenches, hydrological calculations were performed.Leakage to any greater extent did not seem to be a problem in the area. This is the case both for the concrete and the wooden pipes that have served as factory wastewater pipes. A large transport in the lengthwise direction of the sewer trenches was not shown to exist. Instead the greatest risk of transport from a polluted area seems to come from infiltration into wastewater pipes, where the pollutants can flow readily to the recipient or wastewater treatment plant. Rörgravar innehåller ofta grövre material med högre hydraulisk konduktivitet än omgivande jord och kan därför tjäna som spridningsvägar från förorenade områden. Avloppsvatten från fabriksområden kan också misstänkas ge upphov till föroreningar i rörgravar via läckage från avloppsrören.Detta arbete har haft som mål att utreda föroreningssituationen i ledningsgravar och avloppsledningar på Köpmanholmens industriområde, ca 2 mil söder om Örnsköldsvik. För att bedöma ledningsgravarnas potential att sprida föroreningar har också hydrologiska beräkningar har gjorts.Läckage i någon större omfattning från avloppsledningar har inte kunnat påvisas. Detta gäller både betongledningar och den trätub som har utgjort fabriksavlopp på området. Inte heller har någon föroreningsspridning kunnat påvisas i ledningsgravarnas längdriktning. Den största risken för spridning av föroreningar verkar istället vara via infiltration till avloppsledningarna. Detta ger en snabb transport från förorenade områden till recipient eller reningsverk.

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35

Ding, Guo-chun [Verfasser], and Kornelia [Akademischer Betreuer] Smalla. "Analyses of microbial communities at biogeochemical interfaces and their interaction with organic pollutants in soil / Guo-chun Ding ; Betreuer: Kornelia Smalla." Braunschweig : Technische Universität Braunschweig, 2011. http://d-nb.info/1175824798/34.

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36

Moulodi, Shler, and Jessica Thorsell. "Evaluation of the levels of selected trace metal pollutants in groundwater and soil from protected springs in peri-urban Kampala, Uganda." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171837.

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The current urban infrastructure and demographic development of Uganda and in particular of Kampala city is rapid and does not correspond to the planned socio-economic and industrial infrastructure. This project was justified by the existence of numerous peri-urban areas with unplanned and no monitored san-itary as well as water supply systems. The unsanitary handling and disposal, of domestic and industrial solid waste, sewerage and small car related industries pose a serious threat to the quality of the groundwater resources. Field studies were conducted at different occasions between February and March 2012. These included soil and water sampling in and around five protected springs for analysis of the concentrations of four trace metals: Cu, Pb, Cd and Zn. The method used for leaching tests of the soil samples was the European Standard ISO/TS21268-1, and the samples produced were analyzed in a ICP-MS. Addi-tionally, metal concentrations and dissolved organic content of water samples were analyzed. The ICP-MS results showed that the concentration of the trace metals in the waters were below guideline values stated by the WHO, which implies that the residents are not exposed to notable trace metal contamination in the drinking water. As the total metal content in the soils were below the Swedish Environmental Protection Agency (Swedish EPA) guidelines, it was assumed that trace metal contamination was not of significance under the pre-vailing circumstances. However, the leachable metal contents in a number of the soils were high, which may pose a future risk to groundwaters.

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37

Ding, Guo-Chun [Verfasser], and Kornelia [Akademischer Betreuer] Smalla. "Analyses of microbial communities at biogeochemical interfaces and their interaction with organic pollutants in soil / Guo-chun Ding ; Betreuer: Kornelia Smalla." Braunschweig : Technische Universität Braunschweig, 2011. http://nbn-resolving.de/urn:nbn:de:gbv:084-12020911118.

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38

Maloney, Phillip. "Investigation of a Novel Magnesium and Acidified Ethanol System for the Degradation of Persistent Organic Pollutants." Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5987.

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For centuries chemists have sought to improve humankind's quality of life and address many of society's most pressing needs through the development of chemical processes and synthesis of new compounds, often with phenomenal results. Unfortunately, there also are many examples where these chemicals have had unintended, detrimental consequences that are not apparent until years or decades after their initial use. There are numerous halogenated molecules in this category that are globally dispersed, resistant to natural degradation processes, bioaccumulative, and toxic to living organisms. Chemicals such as these are classified as persistent organic pollutants (POPs), and due to their negative environmental and health effects, they require safe, effective, and inexpensive means of remediation. This research focuses on the development and optimization of a reaction matrix capable of reductively dehalogenating several POPs. Initial experiments determined that powdered magnesium and 1% V/V acetic acid in absolute ethanol was the most effective system for degrading polychlorinated biphenyl (PCB), an extraordinarily recalcitrant environmental contaminant. Further studies showed that this matrix also was capable of degrading polychlorinated dibenzo-p-dioxins (PCDDs), polybrominated diphenyl ethers (PBDEs), and four organochlorine pesticides (OCPs); dieldrin, heptachlor, heptachlor epoxide, and chlordane. During this phase of testing, field samples contaminated with chlordane were washed with ethanol and this ethanol/chlordane solution was degraded using the same reaction matrix, thereby demonstrating this technology's potential for “real-world” remediation projects. Finally, a set of experiments designed to provide some insight into the mechanism of dechlorination seems to indicate that two distinct processes are necessary for degradation to occur. First, the passivated outer layer of the magnesium must be removed in order to expose the zero-valent magnesium core. Next, an electron is transferred from the magnesium to the target molecule, causing the cleavage of the halide bond and the subsequent abstraction of either a hydrogen or proton from a solvent molecule. It is anticipated that an understanding of these fundamental chemical processes will allow this system to be tailored to a wide range of complex environmental media. Ph.D. Doctorate Chemistry Sciences Chemistry

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39

Su, Lingcheng. "Soil contamination and plant uptake of metal pollutants released from Cu(In, Ga)Se₂ thin film solar panel and remediation using adsorbent derived from mineral waste material." HKBU Institutional Repository, 2018. https://repository.hkbu.edu.hk/etd_oa/552.

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The Cu(In,Ga)Se2 (CIGS) thin-film solar panels (TFSPs) are widely used in integrated photovoltaic (PV) and solar power systems because of their perfect PV characteristics and ductility. However, the semiconductor layers of these panels contain potentially toxic metals. In this study, the potential environmental pollution arisen by CIGS TFSP treated as construction trash at the end of their useful life was examined. Acid extraction was used to simulate leaching toxicity followed by burying CIGS TFSP material in different soils, namely a synthetic soil, a Mollisol, and an Oxisol, to determine whether metal pollutants might be released into the soil. A vegetable, Brassica parachinensis L. H. Bariley (VegBrassica), was selected to grow in these polluted soils to investigate the uptake of metals and their bioaccumulation. The simulative remediation of contaminated soils was carried out using a remediation module created by the combination of activated carbon and modified mineral waste material (MMWM) in this research. The activated carbon derived from the waste biomass material was produced by an environmental friendly method, and the MMWM was obtained through a thermal dehydroxylation treatment. The physiochemical properties of MMWM, with focusing on mineral phase transformation, were related to the changes in surface morphology due to dehydroxylation occurred during the process of thermal treatment of MMWM samples, and the adsorption performances of metal (lead, Pb) and organic compound (methyl orange, MO) onto this newly modified MMWM were studied. Furthermore, an end-of-life treatment method was designed and proposed for harmless disposal of CIGS TFSP. Various metals, including Pb, zinc (Zn), nickel (Ni), chromium (Cr), gallium (Ga), copper (Cu), indium (In) and aluminum (Al) were found to be released into the soil and caused contamination when scrapped end-of-life CIGS TFSP were buried, and the rates of metal release changed with the variations of both the amounts of CIGS TFSP material in the soil and the soil properties. The increases in concentrations of heavy metals such as Zn, Cu, Ni, Ga, Pb, In, and Cr were correlated with the amounts of CIGS TFSP material added in soils. The Pollution Index and the Nemerow Contamination Index calculated from our results confirmed that, when buried, the CIGS TFSP material polluted the soil. Plants grew well in the synthetic soil and the Mollisol, but those in the Oxisol showed prominent signs of chlorosis and died after 30 days. The bioaccumulation factor (BF) and concentration of Zn were 3.61 and 296 mg/kg, respectively in VegBrassica grown in the synthetic soil with 10% (200 g to 2 kg of soil) of added CIGS TFSP, while the BF and concentration of In were 3.80 and 13.72 mg/kg, respectively in VegBrassica grown in the Mollisol, indicating that bioaccumulation occurred. The thermally treated MMWM samples showed morphological transformation mainly on surface based on the scanning electron microscopy (SEM) observations, and an increasing trend in BET specific surface area (SSA) from 120 to 500 ℃ followed by a decreasing trend up to 1000 ℃. Thermal modification had successfully improved Pb adsorption capacity up to 515 mg/g, corresponding to MMWM modified at 600 ℃ with an SSA of 6.5 m2/g. The MO adsorption capacity was also improved after thermal treatment of MMWM, which performed the best adsorption of 87.6 mg/g at 400 ℃. The adsorption of Pb and MO were mainly chemisorption and monolayer coverage, as pseudo-second-order model and Langmuir equation displayed good relationships of correlation for Pb and MO adsorption data. It is therefore indicated that the newly designed soil remediation modules could significantly remove metals from the contaminated soils. In summary, c

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40

Mousset, Emmanuel, and Emmanuel Mousset. "Integrated processes for removal of persistent organic pollutants : soil washing and electrochemical advanced oxidation processes combined to a possible biological post-treatment." Phd thesis, Université Paris-Est, 2013. http://tel.archives-ouvertes.fr/tel-00976552.

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Soils contaminated by hydrophobic organic pollutants like polycyclic aromatic hydrocarbons (PAHs) are a common concern since they are extremely difficult to remove and their potential toxicological impacts are significant. As an alternative to traditional thermal or physical treatments, soil washing and soil flushing processes appear to be conceivable and efficient approaches, especially for higher level of pollution. However, the treatment of highly loaded soil washing/flushing solutions is another challenge to overcome. In that way, a new integrated approach is suggested: soil washing/flushing processes combined to an electrochemical advanced oxidation process (EAOP) in a combination with a recirculation loop (to save extracting agents) and/or a biological post-treatment step (to minimize energy cost).Extraction efficiency of the extracting agent like hydroxypropyl-beta-cyclodextrin (HPCD) is compared to the traditional non-ionic surfactant Tween 80 in synthetic and real soil washing solutions. A new simple fluorescent sensitive and selective quantification method is developed to monitor Tween 80 oxidation. Two EAOPs were compared: electro-Fenton (EF) and anodic oxidation (AO). Platinum (Pt) (in EF process) and boron doped diamond (BDD) (in both treatment) anodes are the respective electrodes employed to recycle effluents and to consider a biological post-treatment, respectively. Regarding the extracting agent recovery, the biodegradability evolution of effluent and the energy consumption (in kWh (kgTOC)-1) during EAOP, HPCD is more advantageous than Tween 80. However, in terms of extraction efficiency, costs of extracting agents and impact on soil respirometry, Tween 80 is much more efficient. By considering all these advantages and drawbacks, Tween 80 could still appear to be the best option

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41

Mousset, Emmanuel. "Integrated processes for removal of persistent organic pollutants : soil washing and electrochemical advanced oxidation processes combined to a possible biological post-treatment." Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST1130/document.

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Les sols contaminés par les polluants organiques hydrophobes tels que les Hydrocarbures Aromatiques Polycycliques (HAPs) constituent un problème majeur puisqu'ils sont difficilement éliminés et leurs impacts toxicologiques restent significatifs. Comme alternative aux procédés thermiques et physiques traditionnels, les procédés de lavages de sol in situ et ex situ apparaissent être une solution envisageable et efficace et particulièrement pour les fortes pollutions. Cependant, le traitement des solutions fortement chargées de lavages de sol est une autre barrière à surmonter. Une nouvelle approche combinée est proposée pour répondre à ce problème: les procédés de lavages de sol in situ/ex situ combinés à un Procédé Electrochimique d'Oxydation Avancée Electrochimique (PEOA) avec possibilité de recirculer l'effluent (pour réutiliser l'agent extractant) et/ou de combiner avec un post-traitement biologique (pour minimiser le coût énergétique).L'efficacité d'extraction de l'agent extractant tel que l'hydroxypropyl-beta-cyclodextrine (HPCD) est comparé au traditionnel tensioactif non-ionique dénommé Tween 80, dans les solutions synthétiques et réelles de lavages de sol. Une nouvelle méthode sensible d'analyse du Tween 80, basée sur la fluorescence, est développée pour suivre l'oxydation du Tween 80. Deux PEOAs sont comparés : l'électro-Fenton (EF) et l'oxydation anodique (OA). Les anodes de platine (Pt) (dans le procédé EF) et de diamant dopés au bore (BDD) (dans les deux procédés) sont respectivement utilisées pour étudier la recirculation des effluents et la possibilité d'une combinaison avec un post-traitement biologique. Concernant la réutilisation des agents extractants, l'évolution de la biodégradabilité des solutions et l'énergie consommée (en kWh (kg COT)-1) pendant les PEAOs testés, l'HPCD est trouvée être plus avantageuse que le Tween 80. En revanche, en terme d'efficacité d'extraction, de coût des agents extractants et d'impact sur la respirométrie du sol, le Tween 80 paraît être plus avantageux. En prenant en compte tous ces avantages et inconvénients, le Tween 80 pourrait être retenu comme la meilleure solution Soils contaminated by hydrophobic organic pollutants like polycyclic aromatic hydrocarbons (PAHs) are a common concern since they are extremely difficult to remove and their potential toxicological impacts are significant. As an alternative to traditional thermal or physical treatments, soil washing and soil flushing processes appear to be conceivable and efficient approaches, especially for higher level of pollution. However, the treatment of highly loaded soil washing/flushing solutions is another challenge to overcome. In that way, a new integrated approach is suggested: soil washing/flushing processes combined to an electrochemical advanced oxidation process (EAOP) in a combination with a recirculation loop (to save extracting agents) and/or a biological post-treatment step (to minimize energy cost).Extraction efficiency of the extracting agent like hydroxypropyl-beta-cyclodextrin (HPCD) is compared to the traditional non-ionic surfactant Tween 80 in synthetic and real soil washing solutions. A new simple fluorescent sensitive and selective quantification method is developed to monitor Tween 80 oxidation. Two EAOPs were compared: electro-Fenton (EF) and anodic oxidation (AO). Platinum (Pt) (in EF process) and boron doped diamond (BDD) (in both treatment) anodes are the respective electrodes employed to recycle effluents and to consider a biological post-treatment, respectively. Regarding the extracting agent recovery, the biodegradability evolution of effluent and the energy consumption (in kWh (kgTOC)-1) during EAOP, HPCD is more advantageous than Tween 80. However, in terms of extraction efficiency, costs of extracting agents and impact on soil respirometry, Tween 80 is much more efficient. By considering all these advantages and drawbacks, Tween 80 could still appear to be the best option

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42

Wiegert, Charline. "Application of two dimensional compound specific carbon-chlorine isotope analyses for degradation monitoring and assessment of organic pollutants in contaminated soil and groundwater." Doctoral thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-93923.

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Nearly 250,000 sites with past and present potentially polluting activities need urgent remediation within Europe. Major pollutants include organochlorines (OCls), e.g. chlorinated ethenes (CEs) and hexachlorocyclohexanes (HCHs), mainly used as industrial solvents and pesticides, respectively. Due to improper handling and disposal, OCls contaminants are present in the soil or groundwater surrounding sites, where they have been produced or used. CEs and HCHs can undergo degradation by microorganisms indigenous to the soil or groundwater. Therefore natural attenuation (NA), relying on the in situ biodegradation of pollutants, is considered as a cost effective remediation strategy, yet it requires accurate monitoring methods. Compound specific isotope analysis (CSIA) is a powerful tool to provide information on the extent of degradation and, when combining two isotope systems (2D-CSIA), such as carbon (δ13C) and chlorine (δ37Cl), on reaction mechanisms. The diagnostic reaction-specific isotope enrichment factors (εC and εCl) were determined in laboratory experiments for the anaerobic degradation of PCE, TCE (Paper II) and α-HCH (Paper III) by mixed bacterial cultures enriched from CEs and HCHs contaminated sites, respectively. The related mechanism-specific εCl/εC ratios were calculated as 0.35 ± 0.11 (PCE), 0.37 ± 0.11 (TCE) and 0.52 ± 0.23 (α-HCH). These values are smaller than previously reported values for pure cultures. This is explained by the microbial community composition changes observed during degradation of PCE and α-HCH, which also reflect the variability of the microbial community at the field level. Furthermore, εCl/εC ratio might be bacteria specific. These values allowed the estimation of the extent of contaminant degradation at the respective study sites (Paper III and IV). Application of both isotope systems (δ13C and δ37Cl) led to comparable estimates. However the choice of representative ε values is crucial for an accurate assessment. These studies show that CSIA is useful to quantify in situ degradation of OCls contaminants and identify reaction pathways, by combining δ13C and δ37Cl. At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Manuscript.

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43

McMillan, Oliver. "Characteristics and mechanisms of atrazine sorption to biochar for land remediation." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/277807.

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Contaminated land is a widespread, global issue affecting millions of people. Atrazine is a commonly used herbicide which often contaminates groundwater and drinking water supplies and is associated with adverse health outcomes. Biochar is the solid product of pyrolysis and is associated with several environmental benefits. It may be an effective remediation tool when used as a soil amendment. This thesis investigates the mechanisms through which biochar can immobilise atrazine, and the implications of the mechanisms for remediating contaminated land. Nine biochar samples were obtained from the United Kingdom Biochar Research Centre , which were produced from softwood pellets (SWP), wheat straw pellets (WSP), miscanthus straw pellets (MSP), rice husk (RH) and oil seed rape (OSR) each at pyrolysis temperatures of 550°C and 700°C (excluding OSR at 700°C). The sorption mechanisms controlling atrazine sorption to these biochars were determined through various characterisation methods and batch sorption experiments. The sorption tests showed that sorption to each of the standard biochars occurs via multiple simultaneously occurring mechanisms, which are each promoted under certain conditions. Studies investigating sorption kinetics, isotherms and interactions with humic acids showed that for all biochars in this study, pore filling was a significant process through which atrazine is transported to adsorption sites, although poor intraparticle diffusion for softwood and oil seed rape biochars can prevent efficient transport. Wheat straw and rice husk biochars showed effective pore diffusion, resulting in high sorption capacities. Partitioning was associated with poor remediation outcomes and was significant to softwood biochars, although adsorption dominated overall sorption for all other biochars. pH was shown to significantly influence the occurrence of various sorption mechanisms. At low pH values, most biochars showed evidence of electrostatic repulsion between positive atrazine species and the positively charged biochar surface. At intermediate pH values, all biochars showed strong hydrogen bonding between H+ groups on the surface of the biochar and atrazine. A meta-analysis of previous relevant studies provided further evidence for hydrogen bonding of atrazine to biochar and showed that hydrophobic effects likely play little role in adsorption after accounting for the effects of surface area. Varying contributions of π-π EDA interactions, hydrogen bonding involving biochar O- groups, and interactions with ash minerals resulted in different sorption profiles for each biochar at high pH values. In order to further determine the mechanisms controlling sorption at high pH, surface compositions of SWP550, RH700 and OSR550 biochars were modified using hydrofluoric acid. Modification with hydrofluoric acid successfully removed the ash contents of rice husk and oil seed rape biochars and reduced atrazine removal at high pH values. This suggested that the ash fraction increases atrazine removal at high pH through complexation or catalytic hydrolysis. The roles of the various mechanisms are related to remediation outcomes in a novel manner allowing for the improved design of biochar for environmental remediation.

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44

Prange, Joelle, and n/a. "Origin of Dioxins in Queensland: Investigations into the Distribution and Sources of Polychlorinated Dibenzo-P-Dioxins in the Queensland Terrestrial Environment." Griffith University. School of Public Health, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040615.161651.

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Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) are persistent organic pollutants of global concern as they are persistent, toxic and can biomagnify through the food chain. PCDD/Fs are generally regarded as trace contaminants in a number of chemical products and they are formed as by-products from various industrial, chemical and combustion processes. The pollution with PCDD/Fs occurs with the release of these chemicals into the environment, resulting in the contamination of various compartments including; air, soil, sediment and biota. Studies that have investigated the distribution of PCDD/Fs in the environment suggest that the highest concentrations of these pollutants are found in locations with a history of industrial or chemical PCDD/F sources. Queensland is the north-eastern state of Australia. Queensland has a low population density, few industrial activities and is considered predominantly rural. Therefore it was somewhat surprising that elevated concentrations of PCDD/Fs (in particular the higher chlorinated PCDDs) have been observed in soil and sediments samples collected from various locations along the Queensland coast. The concentrations of PCDDs in Queensland samples were comparable to or higher than concentrations in similar matrices from highly polluted regions elsewhere. To investigate the origin of PCDDs in Queensland, the geographical distribution of PCDD/Fs in topsoil was investigated in the coastal and inland environments to provide information on the potential sources and to estimate the extent of the PCDD contamination. Distinct east-west gradients were detected in topsoil collected from bushland areas across the state with elevated PCDD concentrations confined to the coastal region. Within the coastal region, the contamination could not be associated with specific land uses. In fact, the PCDD/F congener profile was similar in the majority of samples from the coastal region, with a dominance of the higher chlorinated PCDDs (in particular OCDD), whereas PCDFs were low or below the limit of detection. The similarity in the PCDD/F congener profiles in the soils along the coastal region indicated that a source of PCDDs of similar origin has resulted in the contamination of soil extending more than 3000 km and estimations suggest that more than 50 tonnes of OCDD is stored in the topsoil of Queensland.s coastal region. Investigation into the vertical distribution of PCDDs in Queensland coastal soils revealed elevated concentrations of PCDDs, (in particular OCDD) in soils to at least 3.5 m. These results indicated that the extent of the PCDD contamination is significantly greater than anticipated and it was estimated that there is in the order of 3 000 tonnes of OCDD stored in Queensland's coastal soils. The specific PCDD/F congener profile in Queensland coastal soils is unlike known PCDD/F source profiles which led to the suggestion that some yet unidentified formation mechanism may have resulted in the contamination. Potential natural sources of PCDD/Fs, including forest fires, geogenic and biogenic processes were assessed as possible origins for the PCDD contamination in Queensland. Elevated concentrations of PCDDs were detected in the atmosphere during a 'prescribed burn'. This study demonstrated that although forest fires influence atmospheric PCDD/F concentrations substantially, forest fires are not the source of PCDDs in Queensland; rather they are an important mechanism for the redistribution of PCDDs and may have attributed to the widespread PCDD contamination. In this study geological materials (oil shale and kaolin) were analysed as a proxy to assess a geogenic origin of PCDDs. Elevated concentrations of PCDDs were observed in the kaolin samples, however similar and higher concentrations were detected in surface and sub-surface soils, suggesting that specific geogenic formation processes investigated are not the source of PCDDs in Queensland. A preliminary indication for a biogenic origin of PCDDs was identified during the anaerobic incubation of sugarcane irrigation sediments. An increase in the concentration of OCDD in the anaerobic treatment, compared to the control was observed after incubation for 90 days. In these same experiments, a dechlorination of OCDD to lower chlorinated (1,4,6,9-substituted) PCDDs was also observed. Similar transformation processes were observed in other anaerobic environments in Queensland, which led to the suggestion that a biogenic formation of PCDDs (possibly from a precursor) may be responsible for the origin of PCDDs in Queensland.

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45

Prange, Joelle. "Origin of Dioxins in Queensland: Investigations into the Distribution and Sources of Polychlorinated Dibenzo-P-Dioxins in the Queensland Terrestrial Environment." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367289.

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Abstract (sommario):

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) are persistent organic pollutants of global concern as they are persistent, toxic and can biomagnify through the food chain. PCDD/Fs are generally regarded as trace contaminants in a number of chemical products and they are formed as by-products from various industrial, chemical and combustion processes. The pollution with PCDD/Fs occurs with the release of these chemicals into the environment, resulting in the contamination of various compartments including; air, soil, sediment and biota. Studies that have investigated the distribution of PCDD/Fs in the environment suggest that the highest concentrations of these pollutants are found in locations with a history of industrial or chemical PCDD/F sources. Queensland is the north-eastern state of Australia. Queensland has a low population density, few industrial activities and is considered predominantly rural. Therefore it was somewhat surprising that elevated concentrations of PCDD/Fs (in particular the higher chlorinated PCDDs) have been observed in soil and sediments samples collected from various locations along the Queensland coast. The concentrations of PCDDs in Queensland samples were comparable to or higher than concentrations in similar matrices from highly polluted regions elsewhere. To investigate the origin of PCDDs in Queensland, the geographical distribution of PCDD/Fs in topsoil was investigated in the coastal and inland environments to provide information on the potential sources and to estimate the extent of the PCDD contamination. Distinct east-west gradients were detected in topsoil collected from bushland areas across the state with elevated PCDD concentrations confined to the coastal region. Within the coastal region, the contamination could not be associated with specific land uses. In fact, the PCDD/F congener profile was similar in the majority of samples from the coastal region, with a dominance of the higher chlorinated PCDDs (in particular OCDD), whereas PCDFs were low or below the limit of detection. The similarity in the PCDD/F congener profiles in the soils along the coastal region indicated that a source of PCDDs of similar origin has resulted in the contamination of soil extending more than 3000 km and estimations suggest that more than 50 tonnes of OCDD is stored in the topsoil of Queensland.s coastal region. Investigation into the vertical distribution of PCDDs in Queensland coastal soils revealed elevated concentrations of PCDDs, (in particular OCDD) in soils to at least 3.5 m. These results indicated that the extent of the PCDD contamination is significantly greater than anticipated and it was estimated that there is in the order of 3 000 tonnes of OCDD stored in Queensland.s coastal soils. The specific PCDD/F congener profile in Queensland coastal soils is unlike known PCDD/F source profiles which led to the suggestion that some yet unidentified formation mechanism may have resulted in the contamination. Potential natural sources of PCDD/Fs, including forest fires, geogenic and biogenic processes were assessed as possible origins for the PCDD contamination in Queensland. Elevated concentrations of PCDDs were detected in the atmosphere during a 'prescribed burn'. This study demonstrated that although forest fires influence atmospheric PCDD/F concentrations substantially, forest fires are not the source of PCDDs in Queensland; rather they are an important mechanism for the redistribution of PCDDs and may have attributed to the widespread PCDD contamination. In this study geological materials (oil shale and kaolin) were analysed as a proxy to assess a geogenic origin of PCDDs. Elevated concentrations of PCDDs were observed in the kaolin samples, however similar and higher concentrations were detected in surface and sub-surface soils, suggesting that specific geogenic formation processes investigated are not the source of PCDDs in Queensland. A preliminary indication for a biogenic origin of PCDDs was identified during the anaerobic incubation of sugarcane irrigation sediments. An increase in the concentration of OCDD in the anaerobic treatment, compared to the control was observed after incubation for 90 days. In these same experiments, a dechlorination of OCDD to lower chlorinated (1,4,6,9-substituted) PCDDs was also observed. Similar transformation processes were observed in other anaerobic environments in Queensland, which led to the suggestion that a biogenic formation of PCDDs (possibly from a precursor) may be responsible for the origin of PCDDs in Queensland. Thesis (PhD Doctorate) Doctor of Philosophy (PhD) School of Public Health Full Text

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46

Salvia, Marie-Virginie. "Développement d’outils analytiques et méthodologiques pour l’analyse et le suivi de composés vétérinaires et stéroïdes hormonaux à l’état de traces dans l’eau et le sol." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10036/document.

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De nombreux produits chimiques se retrouvent dispersés dans l'environnement avec des conséquences parfois néfastes pour les hommes et les écosystèmes. Parmi ces substances figurent les antibiotiques et les stéroïdes hormonaux. Peu de données sont disponibles quant à la présence et le devenir de ces substances dans l'environnement notamment pour le sol, par manque de méthodologies. Nous avons donc mis au point des procédures d'analyse de traces de ces contaminants émergents, dans l'eau et le sol. Nous avons développé des méthodes multi-résidus et inter-familles basées sur des analyses LCMS/ MS. Pour les échantillons aqueux, l'extraction est menée sur phase solide (SPE, OASIS HLB). Les MLQs sont comprises entre 0.09 et 34 ng/L. Pour la matrice solide, la procédure d'extraction est inspirée de la méthode appelée QuEChERS suivie d'une purification SPE. Elle a été validée et des MLQs entre 0.013 et 3 ng/g ont été atteintes. Les tétracyclines et les fluoroquinolones, ont été étudiées séparément car elles ont des propriétés physico-chimiques bien spécifiques les rendant difficiles à extraire correctement du sol avec une méthode inter-familles. La méthode développée sur la matrice sol a permis une étude statistique mettant en exergue l'impact de certains paramètres du sol sur les rendements d'extraction et les effets matrice. Les méthodes ont été appliquées à une étude en colonnes de sol pour obtenir des données sur le transfert, l'accumulation et la dégradation des composés dans le sol Several chemical products are dispersed in the environment and the consequences can be sometimes harmful for humans and the ecosystems. Among these substances appear the antibiotics and the hormonal steroids. Nowadays, only few data are available on the presence and the fate of these substances in the environment in particular for solid matrices, mainly due to a lack of methodologies. Consequently, methods to analyze traces of « emergent » contaminants in water and soil were carried out. Therefore, multi-residues and inter-families procedures based on LC-MS/MS analysis were established. Concerning the aqueous samples, 23 analytes are extracted with the SPE technique (OASIS HLB). MLQs are between 0.09 and 34 ng/L. For the solid matrix, the extraction procedure of 31 compounds is inspired from the method called QuEChERS and followed by a purification step. This methodology was validated and MLQs between 0.013 and 3 ng/g were obtained. Two antibiotics families, tetracyclines and fluoroquinolones, were studied separately as they have specific physical/chemical properties and are therefore difficult to extract from soil with an inter-families method. Then, the method developed for the soil matrix allowed a statistic study which showed the impact of the soil parameters on the recoveries and matrix effects. Finally, the methodologies were applied to a soil column study which allowed obtaining data on the transfer, accumulation and degradation of the substances in soil

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47

Nording, Malin. "Rapid sample preparation and bioanalytical techniques for efficient screening of organic pollutants in the environment." Doctoral thesis, Umeå universitet, Kemi, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-842.

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Large numbers of samples often need to be prepared and analysed in surveys of organic pollutants in the environment, but while the methods commonly used in such surveys can provide abundant detail they are generally costly, time-consuming and require large amounts of resources, so there is a need for simpler techniques. The work underlying this thesis assessed the potential utility of more convenient sample preparation and bioanalytical techniques for rapidly screening various environmental matrices that could be useful complements to higher resolution methods. Initially, the utility of a simplified extraction technique followed by an enzyme-linked immunosorbent assay (ELISA) for detecting polycyclic aromatic hydrocarbons (PAHs) in authentic (i.e. unspiked) contaminated soils was explored. The results showed that there are relationships between the structure and cross-reactivity among compounds that often co-occur with target PAHs. However, their potential contribution to deviations between estimates of total PAH contents of soils obtained using ELISA and gas chromatography-mass spectrometry (GC-MS) based reference methods were limited. Instead, the cross-reactivity of target PAHs and the failure to extract all of the PAHs prior to the ELISA determinations were the main reasons for these deviations. Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were detected in food and feed matrices, as well as in authentic contaminated soils using different bioanalytical techniques – ELISA and two cell-based bioassays: CAFLUX and CALUX (chemically activated fluorescent/luciferase gene expression) assays. In addition, enhanced sample preparation techniques based on accelerated solvent extraction (ASE) were developed. ASE with integrated carbon fractionation (ASE-C) in combination with CAFLUX produced estimates of PCDD and PCDF contents in fish oil and fish meal that agreed well with results obtained using reference methods. Furthermore, results from ELISA and GC-high resolution MS analyses of extracts of PCDD- and PCDF-contaminated soil samples obtained using an adjusted ASE-C technique were strongly correlated. Finally, the thesis reports the first experiments in which the results of CAFLUX, CALUX, and ELISA determinations of PCDDs and PCDFs in extracts of authentic contaminated soil samples were evaluated and compared to those obtained using a reference method. All of the bioanalytical techniques were found to be sufficiently sensitive, selective, and accurate for use in screening in compliance with soil quality assessment criteria. Overall, the improved sample preparation and bioanalytical techniques examined proved to be useful potential complements to conventional methods, enhancing the analytical framework for PAHs, PCDDs, and PCDFs. However, further validation has to be undertaken before they are applied on a large-scale.

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48

Loizeau, Vincent. "Prise en compte d'un modèle de sol multi-couches pour la simulation multi-milieux à l'échelle européenne des polluants organiques persistants." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1168/document.

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Les polluants organiques persistants (POPs) sont des substances toxiques ayant la capacité de se bioaccumuler le long de la chaîne alimentaire. Une fois émis dans l'atmosphère, ils sont dispersés par le vent puis se déposent au sol. Du fait de leur persistance, ils peuvent être réémis depuis le sol vers l'atmosphère et parcourir ainsi de longues distances. Ce processus est couramment appelé « effet saut de sauterelle ». On peut donc retrouver les POPs très loin de leurs sources d'émissions. Pour pouvoir prendre des décisions visant à réduire leur impact environnemental, il est nécessaire de comprendre leur comportement dans l'atmosphère mais également dans les autres milieux, tels que le sol, la végétation ou l'eau. De nombreux modèles numériques de complexité variable ont été développés dans le but de prédire le devenir des POPs dans l'environnement. La plupart d'entre eux considèrent le sol comme un compartiment homogène, pouvant ainsi mener à une sous-estimation des réémissions du sol vers l'atmosphère. Or, du fait de la mise en place de réglementations visant à réduire les émissions anthropiques des POPs, la concentration dans l'atmosphère tend à diminuer et le sol, qui semblait jusqu'alors être seulement un réservoir, devient une source potentielle de POPs pour l'atmosphère. Il apparaît donc nécessaire de coupler les modèles de dispersion atmosphérique à un modèle de sol réaliste. Mes recherches ont permis d'étudier l'impact des interactions entre le sol et l'atmosphère sur la concentration dans les différents milieux. Pour cela, nous avons développé un modèle de sol multi-couches permettant de mieux estimer le profil de concentration dans le sol et les échanges entre ces deux milieux. Une analyse de sensibilité a été effectuée afin d'identifier les paramètres clés dans la détermination des réémissions. Puis ce modèle a été couplé à un modèle 3D de chimie-transport atmosphérique. Une étude de cas à l'échelle européenne a alors été réalisée afin d'évaluer ce modèle et d'estimer l'impact des réémissions sur les concentrations de POPs dans l'environnement Persitent Organic Pollutants (POPs) are toxic substances that bioaccumulate in the food chain. Once emitted in the atmosphere, they are transported by the wind and deposited on soil. Since they are persistent, they can be reemited from soil to atmosphere by volatilization and travel over very long distances. This process is called grasshopper effect. Thus, POPs may be found at significant levels far from their emission source. It is necessary to understand the transport and fate of these pollutants in order to support the decision making process and reduce human exposure to POPs. Regulations over the last decades lead to a decrease of anthropogenic emissions and subsequent decrease of atmospheric concentration. In this context, the soil is no longer a sink of POPs but can be a source to the atmosphere. Many numeric models aim to study the behavior of POPs in the environment. Most of them consider soil compartment as a homogeneous box, leading to an underestimation of reemissions. Then, it appears of great importance to develop more realistic soil models. The objective of my thesis was to develop such a model, with vertical transport within the soil. This model was evaluated against measured concentration soil profile. We also conducted a sensitivity analysis to identify the key parameters involved in the process of reemissions. Then, the soil model was coupled with an atmospheric transport model. A case study was finally undertaken to estimate the impacts of reemissions on global-mass balance of POPs at European scale

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49

Florence, Darlene Christina. "Growth Performance of Six Plant Species and Removal of Heavy Metal Pollutants (Cu, Cr, Pb and Zn) in a Field-Scale Bi-Phasic Rain Garden." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250552547.

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50

Abdelouhab, Malya. "Contribution à l’étude du transfert des polluants gazeux entre le sol et les environnements intérieurs des bâtiments." Thesis, La Rochelle, 2011. http://www.theses.fr/2011LAROS329/document.

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Les outils d’évaluation des risques liés au transfert des polluants gazeux du sol vers les environnements intérieurs comportent de fortes incertitudes quant à la connaissance de certains paramètres et notamment ceux relatifs à l’interface sol-bâtiment : prise en compte des différentes typologies de soubassement, niveau de perméabilité des planchers bas. Ces incertitudes conduisent à une mauvaise estimation de l’impact de ces polluants gazeux sur la qualité d’air intérieur.Afin de contribuer à l’amélioration des modèles d’évaluation pour la gestion des risques vis-à-vis des pollutions gazeuses venant du sol, cette thèse présente dans une première partie, une méthodologie de développement de modèles analytiques adaptés à la prise en compte de différents soubassements, afin de mieux appréhender le transfert de polluants gazeux entre le sol et le bâtiment. Ces modèles ont été développés sur la base d’une analogie avec le transfert des flux de chaleur entre le sol et le bâtiment. Ils traitent, tout particulièrement, des transferts d’air convectifs au niveau de l’interface sol-bâtiment pour différentes typologies de soubassement. Parla suite, les modèles analytiques développés ont été intégrés dans un modèle aéraulique des bâtiments afin d’étudier l’impact des différentes typologies de soubassement sur l’entrée de polluants du sol et donc sur la qualité d’air intérieur résultante.En parallèle, des travaux expérimentaux ont été entrepris afin de compléter la connaissance actuelle relative à la perméabilité à l’air des bétons fissurés, pour laquelle un manque de données a été constaté. D’autre part, les débits d’air convectifs allant du sol vers le bâtiment ont également été quantifiés de façon expérimentale à l’aide de la maison expérimentale ‘MARIA’ dont dispose le CSTB. Ce type de quantification constitue une première base de données expérimentale.Enfin, une dernière partie de cette thèse traite de la réalisation d’un suivi expérimental annuel des performances d’un Système de Dépressurisation des Sols naturels, dans le but d’optimiser à terme les solutions de protection des bâtiments vis-à-vis des polluants gazeux du sol Risk assessment tools related to transfers of gaseous pollutant from soil to indoor environments present large uncertainties relative to the knowledge of certain parameters, particularly those relating to the soil-building interface: considering the different basement typology, permeability level of floor. These uncertainties lead to an inaccurate evaluation of the impact of gaseous pollutants on indoor air quality.In order to contribute to the improvement of risk assessment models of gaseous pollutants from the soil, thiswork present in a fist part the development of analytical and numerical models. These models have been adapted to consider the different basement, in order to estimate the transfer of gaseous pollutants from the soil to the building. An analogy with heat transfer phenomena between soil and building is used to develop these models.They predict convective airflow transfers between soils and building, for different soil-building interface.There after, the analytical model has been incorporated into an airflow model. This model enables us to study the impact of different types of basement on the entry of pollutants from soil and the indoor air quality.Besides, experimental works have been made to complete the knowledge of concrete air permeability, because of a lack of data. Furthermore, the convective airflows from soil to building have been quantified experimentally.These airflows have been determined in the experimental house ‘MARIA’ installed in the CSTB. Suchquantification constitutes the first experimental database.Finally, the last part of this work shows a one-year follow-up study about the ability of natural SoilDepressurisation System. This study has been carried out to optimize the solutions of buildings protection from the soil gaseous pollutants

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