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 Polycyclic Aromatic Hydrocarbons in Bottom Sediment and Bioavailability in Streams in the New River Gorge National River and Gauley River National Recreation Area West Virginia 2002 written by Terence Messinger and published by . This book was released on 2004 with total page 40 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 Bioremediation Technologies for Polycyclic Aromatic Hydrocarbon Compounds written by Andrea Leeson and published by . This book was released on 1999 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycyclic aromatic hydrocarbon compounds (PAHs) are common and challenging contaminants that affect soil and sediments. Methods for treating PAHs have undergone change and refinement in the recent past, and this volume presents the latest trends in PAH remediation theory and practice. The papers in this volume cover topics ranging from the remediation of manufactured gas plant (MGP) sites to the remediation of sediments. The papers present lab and field studies, characterization studies, comparison studies, and descriptions of technologies ranging from composting to thermally enhanced bioremediation to fungal technologies and other innovative approaches.
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 Organic Xenobiotics in the Environment written by P. Baveye and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the continuing fight against organic environmental xenobiotics, the initial success attributed to bioremediation has paled, in part due to the low availability of xenobiotics entrapped within a soil or sediment matrix. This has generated a very significant wave of interest in the bioavailability issue. However, much experimental evidence is puzzling or contradictory, mechanistic theories are embryonic, and implications for the practice of bioremediation or concerning the natural fate of xenobiotics are still tentative. The debate in Europe and the USA is vigorous. Eastern Europe, following the liberalisation of the economy and political life, is evolving in a similar direction. In many cases, however, limited access to literature sources, severe language barriers, and the lack of a strong pluridisciplinary tradition are hampering the adoption of state of the art techniques. Originally intended to allow scientists in East European countries to become acquainted with the key aspects of the bioavailability debate that is unfolding in the scientific literature in the West, and with its implications for bioremediation efforts, the present book presents a very complete coverage of the theoretical and practical aspects of the (limited) bioavailability of organic xenobiotics in the environment.
Download or read book Bioavailability and Biodegradation of Polycyclic Aromatic Hydrocarbons written by Frank Volkering and published by . This book was released on 1996 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Bacterial Biodegradation of Polycyclic Aromatic Hydrocarbons PAH and Potential Effects of Surfactants on PAH Bioavailability written by and published by . This book was released on 1996 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact of Anaerobic Conditions and Microbial Activity on the Bioavailability of High Molecular Weight Polycyclic Aromatic Hydrocarbons in Soils FY00 224 written by and published by . This book was released on 2000 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: The influence of imposed anaerobic conditions on aqueous phase polycyclic aromatic hydrocarbon (PAH) fate was investigated. Highly aged, PAH contaminated soil was incubated with an oxygen scavenging titanium (III) citrate complex, or water, or water that contained nitrate or sulfate in combination with a H2(g), N2(g), or N2:CO2(g) (80:20) headspace. The anaerobic conditions imposed in this study resulted in increased aqueous concentrations of fluoranthene, pyrene, BenzAanthracene and benzoApyrene. BenzAanthracene and benzoApyrene were above a aqueous solubility limits, by as much as an order of magnitude for the latter. The mechanism for this increased PAH solubility is hypothesized to be a combination of oxidation-reduction potential and microbially mediated pH alteration resulting in enhanced solubility of organic material with associated PAH. Methanogenic organisms and sulfate reducing bacteria were seen to have the most significant effect on an increase in aqueous phase PAH. In addition, incubations that changed from anaerobic to aerobic conditions assessed the effect of anaerobiosis conditions on bioavailability. The solvating effect of formalin, used as a metabolic inhibitor, was also examined.
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 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 Trace Polycyclic Aromatic Hydrocarbon Contaminants in San Pablo Bay and Their Bioavailability written by John Justin Baum and published by . This book was released on 2002 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Degradation of Polycyclic Aromatic Hydrocarbons by Actinomycetes written by Leticia Pizzul and published by . This book was released on 2006 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: otic transformation, and probably also the solubilisation, of the high-molecular-weight PAH.
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 Biosurfactant Assisted Bioremediation of Petroleum and Polycyclic Aromatic Hydrocarbons in Aquatic and Soil Media written by Fisseha Andualem Bezza and published by . This book was released on 2016 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt: Petroleum hydrocarbons are organic pollutants of major concern due to their wide distribution, persistence, complex composition, and toxicity. They can bioaccumulate in food chains where they disrupt biochemical or physiological activities and can affect genetic integrity of many organisms, resulting in carcinogenesis, mutagenesis and impairment of reproductive capacity. Polycyclic aromatic hydrocarbons (PAHs) have been recognized as priority pollutants due to their carcinogenic, mutagenic and teratogenic properties. Bioremediation, which utilizes the metabolic versatility of microorganisms such as bacteria and fungi to degrade or detoxify hazardous wastes into harmless substances has been recognized as a sustainable, economic, environmentally friendly and versatile alternative for the remediation of many contaminated environments; however its effectiveness is limited by low bioavailability of nonaquous phase and soil-bound PAHs and petroleum hydrocarbons due to their low aqueous solubility, high hydrophobicity and strong sorption to soil. The purpose of this study was to investigate the PAHs and petroleum hydrocarbons bioavailability and subsequent biodegradation enhancement potential of biosurfactants. Biosurfactants have steadily gained increased significance in environmental applications such as bioremediation dueto several advantages over surfactants of chemical origin, such as biodegradability, environmental compatibility, low toxicity, high selectivity and specific activity at extreme temperature, pH and salinity. A series of experiments was designed to investigate the bioavailability and subsequent biodegradation enhancement potential of the biosurfactants produced by the bacterial strains Bacillus subtilis CN2, Ochrobactrum intermedium CN3, Paenibacillus dendritiformis CN5 and Bacillus cereus SPL_4 in liquid culture and soil microcosms with PAH-enriched microbial consortium from chronically contaminated sites. The biosurfactants exhibited a high level of thermal stability, tolerance to extreme levels of salinity and a positive effect for increasing pH. They were identified after Fourier Transform Infrared (FT-IR) spectrometry, Thin Layer Chromatography (TLC) and Liquid Chromatography/Tandem Mass Spectrometry (LC MS/MS) analyses. The biosurfactants physicochemical characterization displayed vast structural diversity and potent surface active properties of surface tension reduction and emulsion formation with a range of hydrocarbons. The lipopeptide biosurfactants produced by CN3 and CN2 enhanced degradations of used motor oil and petroleum sludge in liquid culture. In a shake flask pyrene degradation study, lipopeptide supplementations at 600 and 300 mg L-1 enhanced pyrene degradation to 83.5% and 67% respectively in 24 days compared to 16% degradation in its absence. However, degradation of pyrene was reduced to 57% as the lipopeptide supplementation was raised to 900 mg L 1. This demonstrates that the biodegradation of pyrene was found to increase with an increase in the lipopeptide concentration up to a threshold level. In a soil bioremedial study, microcosms supplemented with 0.2 and 0.6% (w/w) lipopeptide, 51.2% of 4-ring and 55% of 5- and 6-ring PAHs, 64.1% of 4-ring and 79% of 5- and 6-ring PAHs were removed respectively, compared to, 29% of 4-ring and 25.5% of 5- and 6-ring PAHs removal in the surfactant free control after 64 days of incubation. However, there was no statistically significant change in the degradation rates of low molecular weight PAHs in surfactant amended and surfactant free controls. The degradation of 5 and 6 ring PAHs was significantly enhanced (p
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:
