Doctor of Philosophy, The Ohio State University, 2024, Environmental Science

Historical and current anthropogenic activity combined with land turnovers and rampant vacancies have increased human exposure risk to contaminants. This exposure risk disproportionately affects lower income communities and can have detrimental impacts on human health, particularly children. A management solution is needed to address this widespread contamination of vacant lots. Additionally, federal and state regulators continue to lower residential soil Pb standards which will likely require new risk-based approaches to address urban soil Pb contamination. This dissertation examines three different amendment types (P amendments, Fe oxide containing amendments, and potassium permanganate (KMnO4)) for their ability to address urban Pb soil contamination and reduce human health exposure risk. Remediation strategies that can address both organic and inorganic pollutants are also needed. This is addressed in Chapter 3. This dissertation is written as a series of manuscripts to be submitted to the appropriate journals; this will be reflected by slight differences in formatting. In Chapter 1, readily available P sources (biosolids incinerator ash, poultry litter, biosolids compost, and triple super phosphate) of varying solubility were assessed as soil amendments to reduce Pb bioaccessibility and serve as an inexpensive remediation strategy for urban soil. Contaminated soil from Cleveland, OH was treated with the P soil amendments at a 1:5 Pb:P molar ratio and incubated for 3 months. A slurry analysis was also conducted to assess reduction in bioaccessible Pb independent of time. Pb bioaccessibility was evaluated using US EPA Method 1340 at pH 1.5 and the Physiologically Based Extraction Test (PBET). Treatments were largely found ineffective regardless of IVBA extraction method, incubation duration, slurry analyses, or P source. Method 1340 had one significant treatment (combined poultry litter and BIA) but only resulted in a 8% IVBA Pb reduction. The same treatmen (open full item for complete abstract)

Committee: Nicholas Basta (Advisor); Brian Lower (Committee Member); Steven Lower (Committee Member); Darryl Hood (Committee Member) Subjects: Environmental Science; Soil Sciences

Doctor of Philosophy, Case Western Reserve University, 2016, Civil Engineering

Regulating pesticides in residential surface soil, air, drinking water, and food is a worldwide problem since pesticides exposure can significantly impact human health. Approximate 25% of the world's nations have provided pesticide soil standards, about half have provided pesticide drinking water standards, about 44% have provided pesticide food standards, and only the U.S. has provided pesticide air standards. Most regulatory jurisdictions regulate individual pesticide exposures independently, although the total pesticide exposure risk depends on the cumulative exposure from soil, water, air, and food. Even for a single source such as soil, jurisdiction pesticide guidance values often vary by five, six, and even seven orders of magnitude. The highest of these values are almost certainly too high to protect human health, especially for children, and the exposures are increased even further by food, air, and water. For the most common pesticides, the exposure contributions from different exposure pathways have been quantified by using risk models to convert guidance values into daily maximum implied dose limits. Most jurisdictions have higher pesticide standard values is that they derived their standards independently without consideration of all exposures. Few nations have promulgated standards for all exposures and most nations regulate pesticide standard for only one or two pesticide exposures. For many nations, the sum of the daily maximum implied dose limit from each exposure was compared. Also a ranking system based on standard completeness and numerical values has been developed to quantify how conservative a country's pesticide exposure standards are for each exposure pathway, and for a person's total pesticide exposure. Nations in Europe have better performance in pesticide standard regulations. Also human health risk models and recommended standard values were developed to help regulatory jurisdictions around the world rationalize their guidance values th (open full item for complete abstract)

Committee: Aaron Jennings (Committee Chair); Brynjarsdóttir Jenný (Committee Member); Rhoads Kurt (Committee Member); Xiong Yu (Committee Member) Subjects: Civil Engineering; Environmental Engineering