Toxicology Commons^™

Addressing Uncertainties Of Polychlorinated Biphenyls In Schools, Alice Fan

Master's Projects and Capstones

Despite the potential neurological health deficits resulting from polychlorinated biphenyls, there is a lack of inhalation studies and regulations to protect students and teachers who are widely exposed to PCBs in older (1950 to 1979) schools. To estimate the extent of PCB detections in Los Angeles County schools, I applied a mathematical model to estimate the range of PCB detections in schools built between 1950 and 1984. I estimate the range of 17-34% PCB detections of open schools within Los Angeles County. Next, I reviewed exposure tools provided by the US EPA to bridge the uncertainty gaps between ingestion and …

Pectin And Alginate Extraction To Treat Liquid Cafo Manure, Clare Sunderman

Honors Projects

For this project, various extraction methods were used to extract pectin from Pastinaca Sativa and alginate from Macrocystis. These extractions were then dried and used in treating 250mL of manure along with a CaCl₂ or FeCl₃ coagulant. It was found that CaCl₂ was not as effective as FeCl₃ in coagulating manure. But the results obtained suggest that pectin and alginate obtained with a simpler extraction method is just as effective as the highly purified and refined pectin and alginate produced for the food industry, in the treatment of CAFO manure. The liquid portion of the …

Eelgrass (Zostera Marina) Population Decline In Morro Bay, Ca: A Meta-Analysis Of Herbicide Application In San Luis Obispo County And Morro Bay Watershed, Tyler King Sinnott

Master's Theses

The endemic eelgrass (Zostera marina) community of Morro Bay Estuary, located on the central coast of California, has experienced an estimated decline of 95% in occupied area (reduction of 344 acres to 20 acres) from 2008 to 2017 for reasons that are not yet definitively clear. One possible driver of degradation that has yet to be investigated is the role of herbicides from agricultural fields in the watershed that feeds into the estuary. Thus, the primary research goal of this project was to better understand temporal and spatial trends of herbicide use within the context of San Luis …

Developing A Risk Assessment Protocol To Quantify Distribution And Uptake Of Persistent Organic Pollutants In Glacial Outflows, Kimberley Rain Miner

Electronic Theses and Dissertations

Pollutants released by industrialized nations between 1960 and 2004 have been transported northward through atmospheric processes and deposited into glaciated alpine ecosystems. Many of these chemicals retain their original structure and are absorbed into the biota thousands of miles away from where they were originally utilized. With a warming climate increasing the melt of alpine glaciers, these glaciers may be introducing growing amounts of toxins into the watershed. While studies have demonstrated the existence of resident pollutants within glaciated ecosystems, no one has developed a risk assessment to identify sources and quantity of risk posed by these compounds when released …

Addressing Public Health Risks Of Persistent Pollutants Through Nutritional Modulation And Biomimetic Nanocomposite Remediation Platforms, Bradley J. Newsome

Theses and Dissertations--Chemistry

Due to their relative chemical stability and ubiquity in the environment, chlorinated organic contaminants such as polychlorinated biphenyls (PCBs) pose significant health risks and enduring remediation challenges. Engineered nanoparticles (NPs) provide a novel platform for sensing/remediation of these toxicants, in addition to the growing use of NPs in many industrial and biomedical applications, but there remains concern for their potential long-term health effects. Research highlighted herein also represents a transdisciplinary approach to address human health challenges associated with exposure to PCBs and NPs. The objectives of this dissertation research are two-fold, 1) to develop effective methods for capture/sensing and remediation …

My Experience Exploring The Effects Of Lead (Pb +2) Toxicity In Drosophila Melanogaster Using Sociability Interaction Testing And Microarrays At The University Of Puerto Rico-Rio Piedras In San Juan, Puerto Rico, Charlton Diaz

Honors Theses

Lead is an environmental contaminant widely dispersed throughout the world. Exposure to lead causes neurological damage in humans and may be linked to neurodevelopmental pathologies such as attention deficit hyperactivity disorder, antisocial behavior, and autistic spectrum disorders (ASD). Drosophila melanogaster (fruit flies) have been used to understand the behavioral, synaptic, and molecular changes that occur after developmental exposure to lead and to study ASD-associated pathology. Flies were exposed through the mother and until eclosion to either a lead-laced medium or a control corn-based medium and were isolated until the beginning for the behavioral studies. Sociability testing was done using a …

Arsenic Contamination In Groundwater In Vietnam: An Overview And Analysis Of The Historical, Cultural, Economic, And Political Parameters In The Success Of Various Mitigation Options, Thuy M. Ly

Pomona Senior Theses

Although arsenic is naturally present in the environment, 99% of human exposure to arsenic is through ingestion. Throughout history, arsenic is known as “the king of poisons”; it is mutagenic, carcinogenic, and teratogenic. Even in smaller concentrations, it accumulates in the body and takes decades before any physical symptoms of arsenic poisoning shows. According to the World Health Organization (WHO), the safe concentration of arsenic in drinking water is 10 µg/L. However, this limit is often times ignored until it is decades too late and people begin showing symptoms of having been poisoned.

This is the current situation for Vietnam, …