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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.
11

TOXAPHENE METABOLISM BY THE BOVINE

Maiorino, Richard Morrow, 1941- January 1980 (has links)
No description available.
12

The interactive effects of toxaphene, toxaphene congeners, and hyperglycemia on cultured rat embryos /

Calciu, Cristina Dana. January 1997 (has links)
The presence of persistent organic pollutants, including the pesticide toxaphene, has been reported even in remote regions such as the Arctic and is becoming a health concern. The technical mixture of toxaphene contains over 800 different congeners; however, the numbers decrease along the food chain. Only two major congeners, 2-exo, 3-endo, 5-exo, 6-endo,8,8,9,10,10-octachlorobomane (T2) and 2-exo, 3-endo, 5-exo, 6-endo,8,8,9,10,10-nonachlorobomane (T12) have been found in humans. Information on the embryotoxicity of toxaphene is based only on studies using the toxaphene technical mixture and not its major congeners. Diabetes mellitus, one of the most common maternal illness resulting in congenital defects, is now on an upgrowth trend in many native communities. Xenobiotics, such as toxaphene, may induce interactive effects with hyperglycemia, a teratogenic metabolic agent. / In the present study, the relative dysmorphogenic effects of the toxaphene technical mixture or its congeners (T2 and T12) and the interactive effects of these compounds and high glucose concentrations were investigated using rat embryo culture. Early stage embryos (0--2 somite) were treated with three different doses of the toxaphene technical mixture, T2, T12, or 50:50 mixture of T2 and T12 and incubated in normal or hyperglycemic culture media for 48 h. (Abstract shortened by UMI.)
13

A study of the effects of Toxaphene on the bottom fauna of Paul Lake, British Columbia

Ellickson, Peter Joseph January 1965 (has links)
The density of the animals forming the bottom fauna of Paul Lake, British Columbia has been estimated for two successive seasons, based on 250 Ekman dredge samples from all zones for each year. After the sampling of the first year, the lake was treated with .004 p.p.m. Toxaphene. Density changes in the invertebrate population were considered on the basis of increase, decrease and changes in zonal distribution. Following poisoning and elimination of predatory fish, density increases occurred in the Physidae, Lymnae-idae, Oligochaeta, Planoribae, and Hirudinea. Density decreases occurred in the Watermites, Amphipods, Chiron-omidae, Planaria, Sphaeriidae and Odonata. Tricoptera, Ephemeroptera and Ceratopogonidae were not taken in any of the samples after poisoning. / Science, Faculty of / Zoology, Department of / Graduate
14

The interactive effects of toxaphene, toxaphene congeners, and hyperglycemia on cultured rat embryos /

Calciu, Cristina Dana. January 1997 (has links)
No description available.
15

Total toxaphene and specific congeners in Inuit foods and diets

Chu, Fong Lam, 1976- January 2001 (has links)
Elevated toxaphene levels have been reported in the biota of the Arctic. The purpose of this study is to measure total toxaphene levels in food samples commonly consumed by the Canadian Inuit and study the relationship between concentrations of total toxaphene and individual congeners. A total of 127 Inuit food samples were collected for toxaphene analysis. Total toxaphene and the specific toxaphene congeners including Parlar #26, #40/41, #42, #44, #50 and #62 were detected in the food samples. Total toxaphene concentrations ranged from 13 to 2800 ng/g and various congener concentrations ranged from 0 to 610 ng/g. Concentrations of total toxaphene were strongly correlated with congener concentration in marine mammals and weaker in fish. The sum of congeners Parlar #26, #50 and #62 accounted for 0--15% of total toxaphene in fish and 0--66% in marine mammals. Regression models were used to estimate total toxaphene based on individual or combinations of congener concentrations. Dietary intake was estimated to be 1.07 and 0.78 mug/kg body weight per day in Chesterfield Inlet and Igloolik. Our results show that there is no general conversion factor that can be used to estimate total toxaphene concentrations based on congener measurements.
16

Total toxaphene and specific congeners in Inuit foods and diets

Chu, Fong Lam, 1976- January 2001 (has links)
No description available.
17

Sources and Fate of Organochlorine Pesticides in North America and the Arctic

Jantunen, Liisa M. 21 April 2010 (has links)
Atmospheric transport and air-water exchange of organochlorine pesticides (OCPs) were investigated in temperate North America and the Arctic. OCPs studied were hexachlorocyclohexanes (HCHs, a-, b- and g-isomers), components of technical chlordane (trans- and cis-chlordane, trans-nonachlor), dieldrin, heptachlor exo-epoxide and toxaphene. Air and water samples were taken on cruises in the Great Lakes and Arctic to determine concentrations and gas exchange flux direction and magnitude. The Henry’s law constant, which describes the equilibrium distribution of a chemical between air and water, was determined for several OCPs as a function of temperature and used to assess the net direction of air-water exchange. Air samples were collected in Alabama to investigate southern U.S. sources of OCPs. Chemical markers (isomers, and enantiomers of chiral OCPs) were employed to infer sources and trace gas exchange. Elevated air concentrations of toxaphene and chlordanes were found in Alabama relative to the Great Lakes, indicating a southern U.S. source. Profiles of toxaphene compounds in air were similar to those in soil by being depleted in easily degraded species, suggesting that soil emissions control air concentrations. Gas exchange fluxes in the Great Lakes indicated near-equilibrium between air and water with excursions to net volatilization or deposition. Net volatilization of a-HCH from the Arctic Ocean was traced by evasion of non-racemic a-HCH into the atmosphere.
18

Sources and Fate of Organochlorine Pesticides in North America and the Arctic

Jantunen, Liisa M. 21 April 2010 (has links)
Atmospheric transport and air-water exchange of organochlorine pesticides (OCPs) were investigated in temperate North America and the Arctic. OCPs studied were hexachlorocyclohexanes (HCHs, a-, b- and g-isomers), components of technical chlordane (trans- and cis-chlordane, trans-nonachlor), dieldrin, heptachlor exo-epoxide and toxaphene. Air and water samples were taken on cruises in the Great Lakes and Arctic to determine concentrations and gas exchange flux direction and magnitude. The Henry’s law constant, which describes the equilibrium distribution of a chemical between air and water, was determined for several OCPs as a function of temperature and used to assess the net direction of air-water exchange. Air samples were collected in Alabama to investigate southern U.S. sources of OCPs. Chemical markers (isomers, and enantiomers of chiral OCPs) were employed to infer sources and trace gas exchange. Elevated air concentrations of toxaphene and chlordanes were found in Alabama relative to the Great Lakes, indicating a southern U.S. source. Profiles of toxaphene compounds in air were similar to those in soil by being depleted in easily degraded species, suggesting that soil emissions control air concentrations. Gas exchange fluxes in the Great Lakes indicated near-equilibrium between air and water with excursions to net volatilization or deposition. Net volatilization of a-HCH from the Arctic Ocean was traced by evasion of non-racemic a-HCH into the atmosphere.
19

Lethal Concentrations and Detoxification Time of Toxaphene For Goldfish, Gambusia and Rainbow Trout

Workman, Gar W. 01 May 1959 (has links)
In the past few years the Utah Fish and Game Department, as well as the fish and game departments of other states, has been spending fisheries money for fish eradication on both lakes and streams. The Utah Fish and Game Department recently suggested to the University that research be initiated on the subject of toxaphene as a fish poison. Consequently, a better insight into conditions that exist for a given water type could be developed. To date there is a very small amount of material written on toxaphene. This is due primarily to the fact that toxaphene was not developed until the 19hO's. Toxaphene is used mainly as an insecticide. Such crops as tomatoes, beans, alfalfa, clover and cotton are protected by the use of toxaphene (Hudd and Genelly, 1956).
20

Growth, proximate composition and physiology of Arctic charr exposed to toxaphene and Diphyllobothrium dendriticum

Blanar, Christopher A. January 2001 (has links)
The Arctic charr (Salvelinus alpinus) is a top predator in northern lakes and accumulates persistent lipophilic contaminants. Toxaphene, a major organochlorine contaminant in Arctic charr, is known to be acutely toxic to fish but the effects of dietary exposure have not been examined. Furthermore, lake-resident Arctic charr are frequently infected with larvae of the cestode, Diphyllobothrium dendriticum. The objective of this study was to investigate the effects of toxaphene exposure on Arctic charr growth, nutritional quality, physiology, and susceptibility to infections of D. dendriticum. A preliminary experiment found no effect of toxaphene on charr visceral organ and fat weights, plasma Vitamin A and E and plasma cortisol, although dominance hierarchies within groups may have masked treatment effects. For the main experiment, hatchery-reared Arctic charr were subjected to one of four treatments: (i) a single oral dose of corn oil (control); (ii) a single oral dose of 10 mug/g wet weight toxaphene dissolved in corn oil; (iii) exposure to 15 larval D. dendriticum; and (iv) a combination of both. (Abstract shortened by UMI.)

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