Master of Science, The Ohio State University, 1950, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1918, Graduate School

Committee: Not Provided (Other) Subjects:

Doctor of Philosophy, The Ohio State University, 2019, Public Health

Background: Occupational exposure to airborne chemical agents is a concern for thousands of workers in the United States. Regulatory limits determine the level at which workers may be exposed to chemical agents, and exposure over these limits may indicate a risk for health hazards. The main purpose of this study was to evaluate exposure to specific airborne chemical agents by industry group, by occupation group, and over time using occupational exposure monitoring data in order to determine potential groups of workers that should be targeted for intervention and future research. In addition, this study used an auto-coding program in order to code the free text job descriptions to standardized occupation codes for the first time, as only industry was provided as a standardized code within the applied dataset. Methods: The study employed the Occupational Safety and Health Administration (OSHA) Integrated Management Information System (IMIS) and Occupational Safety and Health Information System (OIS) databases to evaluate personal air monitoring samples taken from 1979 through 2015. The OSHA IMIS/OIS is the largest occupational exposure database in the United States. Analyses were conducted in SAS. Exceedance fractions over an agent's threshold limit value (TLV) or permissible exposure limit (PEL) were calculated through frequency analyses and linear regression was used to determine changes in geometric mean of exposure level over time. Statistical procedures included using logistic regression and mixed-model analyses to obtain odds ratios for the likelihood of exposure over an agent's TLV or PEL in comparison to other industry or occupation groups. The NIOSH Industry and Occupation Computerized Coding System (NIOCCS) version 3.0 was used to auto-code free text job descriptions into standardized occupation codes. Results: Examination of benzene, toluene, ethyl benzene, and xylene (BTEX) occupational exposure indicated that manufacturing industry groups inclu (open full item for complete abstract)

Committee: Michael Bisesi PhD (Advisor); John Crawford PhD (Advisor); Carolyn Sommerich PhD (Committee Member); Christopher Weghorst PhD (Committee Member); Olorunfemi Adetona PhD (Committee Member) Subjects: Occupational Health; Public Health

Doctor of Philosophy, The Ohio State University, 1983, Graduate School

Committee: Not Provided (Other) Subjects: Chemistry

Doctor of Philosophy, The Ohio State University, 2003, Chemistry

Advances in surface broad bandwidth sum frequency generation (BBSFG) spectroscopy and investigations of liquid surfaces are discussed in this dissertation. The technique implemented uses a double amplifier ultrafast laser system to produce a narrow bandwidth visible beam and a broad bandwidth infrared beam. The two beams are overlapped in time and space on a liquid surface to produce a broad bandwidth sum frequency signal. The double amplifier system allows for higher peak powers resulting in a stronger sum frequency generation response from characteristically low signal liquid surfaces. Several organic liquids are investigated using BBSFG spectroscopy and Raman spectroscopy to investigate the surface structure and the bulk liquids, respectively. The series of liquids selected are applicable to atmospheric aerosol processing. Initially, a surrogate hydrophilic compound ethylene glycol was investigated. In addition to ethylene glycol, several aromatic compounds were probed at their air-liquid interfaces. The aromatic compounds studied were benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, and mesitylene. The final aromatic compound to be studied was 1-methyl naphthalene. The surface of the neat 1-methyl naphthalene liquid is dramatically altered upon the addition of small amounts of water into the bulk liquid.

Committee: Heather Allen (Advisor) Subjects: Chemistry, Physical

Master of Science, University of Akron, 2010, Chemistry

A method for solventless extraction and determination of gasoline components in water has been developed. This method uses silicone polycarbonate permeation membranes to extract the components, and collect them on a Tenax TA adsorbent. Samples were thermally desorbed into a gas chromatograph with flame ionization detection for separation and determination of the components. Time-weighted average (TWA) concentrations were determined by plotting the amount of analyte collected versus the product of concentration and time (ppb•hr). A linear response was seen in the TWA curves for benzene, toluene, ethylbenzene and the three isomers of xylene (BTEX). These components had detection limits from 1.4 ppb for m- and p-xylene to 2.7 ppb for toluene. The effects of temperature and common environmental contaminants were examined. The advantages of this method include being environmentally friendly due to the lack of solvent and having less steps for analysis than many standard methods.

Committee: James Hardy PhD (Advisor) Subjects: Analytical Chemistry; Chemistry; Environmental Science; Experiments