Toxicology Commons^™

Microbial Competition In The Biodegradation Of Phenol, Mary Ellen Frank

Theses

Three phenol degraders were isolated from the mixed liquor of the Livingston, NJ municipal treatment plant. Shaker flask experiments using one of the degraders (a Pseudomonas sp.) resulted in the determination of its kinetic rate constants. The second phenol degrader (a Xanthamonas) lost its phenol degrading ability while being stored, and its kinetic rate constants could not be determined. The third phenol degrader (a Pseudomonas cepacia) formed flocs which interfered with the spectrophotometric determination of biomass and therefore its kinetic rate constants also could not be determined.

Mixed culture experiments were carried out using a the Pseudomonas sp. and a …

Thermal Desorption Of Hazardous And Toxic Organic Compounds, Manuel S. Nolau

Theses

The purpose of this thesis is to study the thermal desorption behavior of toxic organic compounds, specifically o-xylene, p-xylene, ethyl benzene, p-chlorotoluene, and anthracene, from soil with respect to temperature and time, and to develop a mathematical model that will describe this desorption behavior. The model will allow prediction of the concentration of an organic contaminant in commercial soil desorption system over time given a known set of parameters of the specific chemical as well as flow rate and temperature. For this purpose, two sets of experiments were done: These are identified as 1. Thermal desorption and 2. plug flow …

Study Of An Analytical Method For Benzo(A)Pyrene Metabolites In Human Urine, Zheng Ouyang

Theses

A method developed by Becher and Bjorseth for analysis of PAH metabolites in urine was employed to investigate human exposure to benzo(a)pyrene (BaP) - an ubiquitous environmental carcinogen. Preliminary results are presented showing the relationship between exposure to BaP and urinary elimination. Although the correlation between the two variables is not statistically significant, there appears to be a positive association with selected exposure varibles such as smoking. The identification of an association may establish urinary BaP as a marker of exposure.

However, detailed study of the analytical procedure indicated that recoveries with this method were as low as 3-8% for …

A Quantitative Assessment Of Minerals Of Toxicological Importance In Utah Fast Foods, Lisa R. Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

X-ray flourescence (XRF) and atomic absorption spectrophotometry (AAS) measurements for manganese, iron, copper, and zinc were compared for 96 samples of 21 foods from different sources. Correlation coefficients were 0.94 for manganese, 0.99 for iron, 0.93 for copper, and 0.91 for zinc for XRF vs. AAS determinations.

Similiar comparisons were performed on 228 samples of fast foods purchased in Utah retail outlets. Correlation coefficients ranged from 0.91 for copper to 0.97 for iron and zinc. Comparisons of values generated by XRF for manganese, iron, copper, zinc, selenium, arsenic, and aluminum to values certified by the National Bureau of Standards indicated …

Selenium And Iron In The Rat Intestine: Effects On Lipid Peroxidation, Sileny Vega

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Effects of Fe and Se status on GSHPx activity and lipid peroxidation in liver and intestinal mucosa were studied. Rats were Se and Fe supplemented (+Se+Fe), Se-deficient and Fe-supplemented (-Se+Fe), Se supplemented and Fe overloaded (+Se++Fe) by intramuscular injection, or Se deficient and Fe overloaded (-Se++Fe) for 20d. Fe overloaded tissues had more Fe, but hemoglobin was unaffected. Liver and mucosal GSHPx activity was low in Se-deficient rats. Thiobarbituric acid reactive substances (TBARS) were higher in Fe overloaded and -Se++Fe vs +Se++Fe tissues. Mucosal TBARS was higher in -Se++Fe rats gavaged with CBrCl₃. In experiment 2, Fe overload …

Immunologic, Hematologic, And Endocrine Responses To Subacute And Subchronic Exposures To Graded, Subanesthetic Levels Of Nitrous Oxide In Cd-1 Mice, Charles E. Healy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrous oxide (N₂O) oxidizes vitamin B12. disrupting deoxyribonucleic acid (DNA) synthesis. Occupational exposures to subanesthetic levels of the gas have been documented that may result in suppressed proliferative cell activities. Male CD-I mice were exposed to 0, 50, 500, and 5000 parts of N₂O per million parts of air (ppm) for 6 hr/day, 5 days/week for 2 and 13 weeks. Splenic lymphocytes were assayed for responsiveness to mitogens and for the ability to produce interleukin-2 (lL-2) . Tritiated-thymidine ([³H]-TdR) uptake was measured in CD-I splenic lymphocytes cultured in a mixed-lymphocyte culture (MLC). Cytolytic cell …

Environmental Assessment In Bioethanol Technology Using Immobilized Yeast Cells, Minoo Kandy Zarnegar

Theses

This study is undertaken from the standpoint of water pollution evaluation in bioethanol technology, using immobilized yeast cells. Evaluation of water pollution caused by immobilized yeast fermentation is the main objective of this research.

The pollution in water remaining at the end of ethanol production, which is normally discharged in the wastewater stream, has been analyzed by the measurement of biological oxygen demand (BOD), since BOD measurement is one of the widely used parameters for water pollution evaluation. BOD obtained from produced water (stillage) was between the range of 115- 360 mg/l. The variation in BOD depended upon the removal …

Agenda For Action - Casco Bay, Department Of Environmental Protection

Maine Collection

Agenda For Action - Casco Bay

Department of Environmental Protection, Augusta, Maine (January, 1989)

Contents: Introduction / The Problems : Bacteria, Toxics, Nutrients / The Solutions / Recommendations / References

Maine Nonpoint Source Pollution Assessment Report, Bureau Of Water Quality Control

Maine Collection

Maine Nonpoint Source Pollution Assessment Report

Prepared by the Maine Department of Environmental Protection, Bureau of Water Quality Control, Augusta, Maine 1989.

Contents: Executive Summary / Introduction / Methodology / Statewide Water Quality Summary / State And Local Agency Programs for Control of Nonpoint Source Pollution / Process for Identification of Best Management Practices and Associated Standards / List of References / List of Figures / List of Tables