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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Heavy Metal, Organochlorine Pesticide and Polychlorinated Biphenyl Contamination in Arctic Ground Squirrels (Spermophilus Parryi) in Northern Alaska

Allen-Gil, S. M., Landers, D. H., Wade, T. L., Sericano, J. L., Lasorsa, B. K., Crecelius, E. A., Curtis, L. R. 01 December 1997 (has links)
Heavy metal and organochlorine (OC) concentrations, including organochlorine pesticides and polychlorinated biphenyl congeners (PCBs), were determined in arctic ground squirrels (Spermophilus parryi) from three sites in the Brooks Range of northern Alaska in 1991-93. Heavy metals were present in most squirrel livers collected, with concentrations of trace elements (As, Cd, Hg, Ni, and Pb) averaging below 1 μg/g wet weight. Hexachlorobenzene (HCB), p,p'-DDE, gamma hexachlorocyclohexane (γ-HCH), trans-nonachlor, and PCBs 138, 153, and 170 were the most frequently detected OCs in fat and liver. Average concentrations of individual OC analytes were below 20 ng/g wet weight in liver and below 15 ng/g wet weight in fat. Rank correlations indicate that concentrations of heavy metals and of OCs accumulate in concert with one another (As, Cd, Cu, and Zn; PCBs 138, 170, and 180). Although heavy metal and OC concentrations are low relative to other areas and other arctic species, the occurrence of these compounds illustrates the global pervasiveness of persistent organic compounds and the potential for bioaccumulation in the terrestrial arctic food web.
122

Determination, mobilization and dechlorination of polychlorinated biphenyl (PCB) compounds in contaminated soils

Wu, Qixiang January 2001 (has links)
No description available.
123

Neurobehavioral and Neuroendocrine Assessment of Rats Perinatally Exposed to Polychlorinated Biphenyls: A Possible Model for Autism

Krishnan, Dena K. 25 June 2007 (has links)
No description available.
124

Investigating the Effects of Polychlorinated Biphenyls on Circulating Oxytocin Levels, Area of the Paraventricular Nucleus and Social Behavior in Juvenile Male Rats

Jolousjamshidi, Banafsheh 05 July 2007 (has links)
No description available.
125

Comparison Between PCB Exposure and Hypothyroidism: Behavioral Development in Sprague-Dawley Rats

Toth, Cynthia L. 29 July 2009 (has links)
No description available.
126

OCCURRENCE OF NONYLPHENOL POLYETHOXYLATES AND POLYCHLORO-BIPHENYLS IN AQUEOUS AND SOLID PHASES ALONG TWO PILOT-SCALE WASTEWATER TREATMENT PLANTS

GONZÁLEZ-FERNÁNDEZ, MARIA-CHRISTINA 27 September 2005 (has links)
No description available.
127

BIOACCUMULATION OF POLYCHLORINATED BIPHENYLS IN THE NORTHERN DIAMONDBACK TERRAPIN (Malaclemys terrapin terrapin)

Ismail, Niveen January 2010 (has links)
Polychlorinated biphenyls (PCBs) are persistent organic pollutants that can bioaccumulate in organisms. PCBs are documented endocrine disrupting chemicals and are known to cause developmental, reproductive, and neurobiological disorders. This study examines the bioaccumulation of PCBs in the northern diamondback terrapin (Malaclemys terrapin terrapin), a species that is endemic to the brackish waters of the East Coast salt marshes of the United States. The two populations studied are located in Cape May County, NJ, a site with low levels of contamination and Jamaica Bay, NY, which is a highly contaminated site. While PCBs bioaccumulation has been extensively researched, many studies involve lethal sampling techniques. Such techniques can be detrimental to populations and may not be viable for long-term studies. This study examined the utility of the chorioallantoic membrane (CAM) as a non-lethal sampling technique for PCB analysis. In order to determine the viability of the CAM, maternal transfer of contaminants was also analyzed. Ten terrapin samples from each field location were analyzed. Egg and CAM samples were obtained from both field sites and liver samples were also collected from Cape May County terrapins. PCB levels and congener profiles were similar in both field locations. While PCB congeners were detected in liver, egg, and CAM samples, less chlorinated congeners preferentially partitioned in the CAM. Liver and egg sample PCB concentrations were strongly correlated, but the CAM concentrations were weakly correlated to liver and egg samples. Examination of homolog groups indicated a strong correlation between hexachlorinated biphenyls in all three sample types. Preliminary study results indicated that maternal transfer of PCB contaminants does occur with selective partitioning of congeners into the CAM. / Biology
128

Particulate and gas-phase PCBs and OH-PCBs in Chicago air

Awad, Andrew Magdi 01 July 2015 (has links)
This study extends the work we have previously done by reporting on both gas-phase and particulate phase PCB concentrations in Chicago air as well as giving a first report on airborne OH-PCBs in Chicago. Gas phase PCB concentrations ranged from 43.1 pg/m³ to 2250 pg/m³, with an average concentration of 594 pg/m³ ± 445 pg/m³, and exhibited strong temporal trends. Particulate phase PCBs accounted on average for 4.3% of total PCBs in a sample. OH-PCBs were detected in both the gas and particulate phase and exhibit characteristics of either emission sources or atmospheric reactions depending on the congener.
129

Bioremediation of polychlorinated biphenyls (PCBs) on contaminated soils : a case study of Rietvlei Farm Borehole No. 11, Limpopo Province, South Africa

Sengani, David January 2015 (has links)
MENVM / Department of Ecology and Resource Management / Polychlorinated biphenyls (PCBs) are worldwide environmental pollutants which contaminate the environment through careless disposal practices and accidental spills or leakages from electrical transformers. These organic compounds are lipophilic chemicals soluble in fats, slightly soluble in water and readily bioaccumulated in the fatty tissues of fish, birds, animals and humans. The main objective of this study was to isolate and identify PCB degrading bacteria from PCB contaminated soils and test them for their degradation ability of PCBs in natural habitat conditions. Three bacteria species which comprise of Gram negative and Gram positive microorganisms were isolated and identified through biochemical tests, catalase tests, oxidase tests and morphological study and included Burkholderia cepacia, Pasteurella pneumotropica and Enterococcus faecalis. The results indicated that, there was an overall decrease of PCB concentration level and the readings ranged between -1.51 and -1.79 respectively for all the microorganisms. Enterococcus faecalis remove as much as 32% of PCBs in the contaminated soil samples. Whereas Pasteurella pneumotropica could remove 24% of PCBs, Burkholderia cepacia 21% of PCBs and the mixed culture removed 23%. Data showed that the 3 bacterial strains could tolerate high concentration of PCBs. The results provided the evidence that naturally occurring bacteria in soil contaminated with PCBs have the potential to degrade PCBs. Statistical analysis showed that there was a significant positive correlation between bacteria growth and treatment with a coefficient of (r) =0.1459 and p value <0.001.
130

Analysis of semi-volatile organic contaminants and their accumulation in remote aquatic ecosystems of the western U.S. /

Ackerman, Luke K. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 102-117). Also available on the World Wide Web.

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