Download or read book Bioavailability of Polycyclic Aromatic Hydrocarbons PAHs in Soils written by Luchun Duan and published by . This book was released on 2014 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fate and distribution of contaminants in soil are controlled by their bioavailability which is of great importance to human and ecological health risk assessments. Risk assessments based on total contaminant loading that assumes 100% bioavailability in soils may overestimate exposure resulting in unnecessarily low remediation goals. Such remediation goals may be neither technically or economically feasible.
Download or read book Polycyclic Aromatic Hydrocarbon Bioavailability in Contaminated Soils and Sediments written by Joseph Paul Kreitinger and published by . This book was released on 2007 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessment of Bioavailability of Polycyclic Aromatic Hydrocarbon PAH in Coal tar Contaminated Soils written by Insoo Joo and published by . This book was released on 2004 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: The bioavailability of polycyclic aromatic hydrocarbons (PAHs) in coal-tar contaminated soils plays an important role in determining the risk of these compounds to the environment and humans. Developing an understanding of organic compounds bioavailability will assist in improving risk assessment and developing bioremediation strategies. In the first part of study, the degradation of 16 EPA priority PAHs in soil slurry reactors were investigated along with the change in microbial population. Using DAPI-stained organisms, maximum microbial populations were found to correspond with the depletion of 2- and 3-ring PAHs. Degradation of PAHs was sequential with the 2- and 3-ring PAHs degrading first, followed by the 4- and 5-ring PAHs. There was negligible degradation of 6-ring PAHs. The Modified Gompertz equation, an empirical model, was used to estimate the lag phase, degradation rate, and maximum degraded fraction of individual PAHs. The Monod equation was also applied but did not model the experimental data well especially the change in microorganism population. In the second part of study, several chemical methods were performed to assess the bioavailability of PAHs in three coal-tar contaminated soils from former manufactured gas plant (FMGP) sites. The methods tested were hydroxypropyl-[beta]-cyclodextrin (HPCD), persulfate oxidation, acetone-water mixture extraction, butanol extraction, and solid phase extraction using XAD-2. Residual PAHs in each soil following extraction were compared with the PAHs remaining after biodegradation in soil slurry reactors. Of the five methods tested, the XAD-2 desorption method was determined to the best method for predicting the bioavailability in coal-tar contaminated soils.
Download or read book WHO Guidelines for Indoor Air Quality written by and published by World Health Organization. This book was released on 2010 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents WHO guidelines for the protection of public health from risks due to a number of chemicals commonly present in indoor air. The substances considered in this review, i.e. benzene, carbon monoxide, formaldehyde, naphthalene, nitrogen dioxide, polycyclic aromatic hydrocarbons (especially benzo[a]pyrene), radon, trichloroethylene and tetrachloroethylene, have indoor sources, are known in respect of their hazardousness to health and are often found indoors in concentrations of health concern. The guidelines are targeted at public health professionals involved in preventing health risks of environmental exposures, as well as specialists and authorities involved in the design and use of buildings, indoor materials and products. They provide a scientific basis for legally enforceable standards.
Download or read book Measuring and Reducing Bioavailability of PAHs in Soils written by Huan Xia and published by . This book was released on 2017 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycyclic aromatic hydrocarbons (PAHs) are a group of organic contaminants that are widely distributed in soils. Some PAHs are potent human carcinogens. When released into soils, PAHs are often emitted within a certain source matrix (e.g. soot, coal tar or oils). In addition to the diversity of the PAH source matrix, soils are also very heterogeneous mixtures containing many different components, such as sand, clay, organic matter and black carbon which can have varying capacity and affinity for sorbing hydrophobic organic contaminants. Together, these different matrices in soil control the PAH bioavailability to receptors such as soil invertebrates and human beings via various exposure pathways. In terms of soil remediation, numerous recent studies have demonstrated the prominent effectiveness of condensed, black carbon particles, such as biochar or activated carbon (AC), in reducing the bioavailability of hydrophobic contaminants in ecological receptors.
Download or read book Bioavailability of Polycyclic Aromatic Hydrocarbons and Its Impact on Bioremediation written by Ilia Rostami and published by . This book was released on 2010 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis investigated the microbial degradation of polycyclic aromatic hydrocarbons (PAHs) in liquid and soil matrices and the influence of PAH bioavailability on biodegradation and ecological/ human exposure. These research themes were investigated using three PAH contaminated Soils collected from a former wood preservation site, a former manufacturing gas plant and a tram yard site in South Australia.
Download or read book Soil Biological Communities and Ecosystem Resilience written by Martin Lukac and published by Springer. This book was released on 2017-10-06 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume explores current knowledge and methods used to study soil organisms and to attribute their activity to wider ecosystem functions. Biodiversity not only responds to environmental change, but has also been shown to be one of the key drivers of ecosystem function and service delivery. Soil biodiversity in tree-dominated ecosystems is also governed by these principles, the structure of soil biological communities is clearly determined by environmental, as well as spatial, temporal and hierarchical factors. Global environmental change, together with land-use change and ecosystem management by humans, impacts the aboveground structure and composition of tree ecosystems. Due to existing knowledge of the close links between the above- and belowground parts of terrestrial ecosystems, we know that soil biodiversity is also impacted. However, very little is known about the nature of these impacts; effects on the overall level of biodiversity, the magnitude and diversity of functions soil biodiversity generates, but also on the present and future stability of tree ecosystems and soils. Even though much remains to be learned about the relationships between soil biodiversity and tree ecosystem functionality, it is clear that better effort needs to be made to describe and understand key processes which take place in soils and are driven by soil biota.
Download or read book Toxicological Profile for Polycyclic Aromatic Hydrocarbons written by and published by . This book was released on 1995 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bioavailability of Contaminants in Soils and Sediments written by National Research Council and published by National Academies Press. This book was released on 2003-05-03 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bioavailability refers to the extent to which humans and ecological receptors are exposed to contaminants in soil or sediment. The concept of bioavailability has recently piqued the interest of the hazardous waste industry as an important consideration in deciding how much waste to clean up. The rationale is that if contaminants in soil and sediment are not bioavailable, then more contaminant mass can be left in place without creating additional risk. A new NRC report notes that the potential for the consideration of bioavailability to influence decision-making is greatest where certain chemical, environmental, and regulatory factors align. The current use of bioavailability in risk assessment and hazardous waste cleanup regulations is demystified, and acceptable tools and models for bioavailability assessment are discussed and ranked according to seven criteria. Finally, the intimate link between bioavailability and bioremediation is explored. The report concludes with suggestions for moving bioavailability forward in the regulatory arena for both soil and sediment cleanup.
Download or read book Provisional Guidance for Quantitative Risk Assessment of Polycyclic Aromatic Hydrocarbons written by and published by . This book was released on 1993 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bioavailability of Polycyclic Aromatic Hydrocarbons in Soils written by Brian John Reid and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bioavailability of Polycyclic Aromatic Hydrocarbons in the Aquatic Environment written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the environment and have been shown to elicit toxicity in humans and other organisms. Therefore, it is important to monitor environmental concentrations of PAHs. Toxicologically, we are concerned not only with the total PAH concentration but, with that fraction available to partition into an organism (bioavailable fraction). This research fits within three areas concerning bioavailability of PAHs including; 1) development of methods to measure bioavailability in the field, 2) identification and characterization of mechanisms controlling bioavailability and, 3) development of models to predict bioavailability in the natural environment. In the first phase of this research, the role of black carbon (BC) in the bioavailability of PAHs in soil and sediment was examined by measuring sorption in systems containing BC, natural organic matter (NOM), and microorganisms. A model was developed to predict the bioavailable fraction of PAHs and factors that may alter sorption in the natural environment from that predicted by laboratory models were examined. In the second phase of this research, a novel passive sampling device was developed to monitor truly dissolved PAH concentrations in water. Sorption isotherms of pyrene-d10 were measured for diesel soot (DS), Suwannee River NOM, Leonardite humic acids (HA), DS previously exposed to NOM and HA, in binary systems containing both DS and NOM, and to DS exposed to lake water. When DS was previously exposed to NOM, competition for sorption sites was observed. However, when both pyrene-d10 and NOM were introduced to DS simultaneously, less competition occurred and sorption was predicted within 92% of observed values using additive sorption models (based on the unit-normalized Freundlich model and Polyani-Dubinin-Manes model). Weathering of DS significantly reduced adsorption capacity but many strong sorption sites still remained, possibly due to renewal of sorption sites b.
Download or read book Bioavailability and Biodegradation of Organic Xenobiotic Recalcitrant Polycyclic Aromatic Hydrocarbons PAHs in Different Soil Environments written by Jamshid Jazestani and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Bacterial isolates from soils contaminated with a large range of organic pollutants were tested for their ability to metabolise selected recalcitrant PAHs as their sole energy and carbon source. Plating of soil microorganisms isolated from 12 petroleum-contaminated soils on solid medium, supplemented with the PAH phenanthrene as sole carbon source, yielded 228 phenanthrene-degrading bacterial strains, of which 60 were further characterized. Southern DNA-DNA hybridization identified 14 of the 60 colonies as potentially competent in naphthalene degradation (ndoB Positive). The 14 bacterial isolates were further screened for their capacity to mineralize six radiolabelled PAHs serving as their sole carbon and energy source. Under such conditions, bacterial isolate strain S65 cumulatively mineralized 61% of phenanthrene, 61% of pyrene, and 24% of fluoranthene over a 9-day period, but could not degrade naphthalene, anthracene or fluorene.Three different ...
Download or read book PAHs written by Peter E. T. Douben and published by John Wiley & Sons. This book was released on 2003-07-25 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycyclic aromatic hydrocarbons (PAHs), or polyarenes, are one of the largest and most structurally diverse class of organic molecules known. High percentages of polyarenes, representing a wide range of molecular sizes and structural types, are present in coal tars and petroleum residues. The major sources of PAHs are crude oil, coal and oil shale. The fuels produced from these fossil sources constitute the primary source of energy for the industrial nations of the world, and the petrochemicals from these raw materials are the basis of the synthetic fibre and plastics industries. PAHs are however, widespread pollutants and their impact on the environment and human health must be monitored and controlled. This book will review and assess our scientific understanding of the ecological exposure and effects PAHs have in different environments and habitats. It will accomplish this by taking the recipients of the pollution in the environment as starting points and working its way back through pathways to access what is required for our understanding of effects and rationale for control. Although this book will concentrate on ecological exposure of PAHs, the general impacts of PAHs on human populations will be touched upon. It is thought to be the first book to focus on the ecological aspects of PAHs.
Download or read book Measuring and Reducing the Bioavailabity of Polycyclic Aromatic Hydrocarbons in Contaminated Soil written by Jose Luis Gomez Eyles and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A large number of chemical methods to measure the bioavailability of polycyclic aromatic hydrocarbons (PAHs) have been proposed over the last decades. The main aim of this thesis is to evaluate the ability of these chemical methods to predict PAH bioavailability to earthworms and plants.
Download or read book A Study of the Effects of Nonaqueous Phase Liquits NAPLs on the Bioavailability of Polycyclic Aromatic Hydrocarbons Pahs to Worms and Bacteria written by Antonio Quin̋ones-Rivera and published by . This book was released on 2004 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Functions of Natural Organic Matter in Changing Environment written by Jianming Xu and published by Springer. This book was released on 2016-08-23 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Functions of Natural Organic Matter in Changing Environment presents contributions from the 16th Meeting of the International Humic Substances Society (IHSS 16) held in Hangzhou, China on September 9-14, 2012. It provides a comprehensive and updated research advance in the field of characterization, function, application of humic substances (HS) and natural organic matter (NOM) in environment, agriculture, and industry. A broad range of topics are covered: i) formation, structure and characteristics of HS and NOM; ii) HS/NOM and carbon sequestration; iii) HS/NOM and biogeochemical cycling of nutrients; iv) HS/NOM and the environmental processes of toxic elements and anthropogenic organics; v) HS/NOM, naturally occurring and engineered nanoparticles; vi) HS/NOM, biodiversity and ecosystem health; vii) HS/NOM in water and water treatment; viii) characterization and function of biochar in the environment; and ix) industrial products and application of HS. The book will be an invaluable reference for chemists, biologists, environmental scientists, ecologists, soil scientists, water scientists, agronomists, global change researchers and policy makers. Jianming Xu is Professor and Director at the Institute of Soil and Water Resources and Environmental Science, Zhejiang University, Hangzhou, China. Jianjun Wu is Professor at the Institute of Soil and Water Resources and Environmental Science, Zhejiang University, Hangzhou, China. Yan He is Associate Professor at the Institute of Soil and Water Resources and Environmental Science, Zhejiang University, Hangzhou, China.
