There is currently high demand for new building materials which are considered "environmentally friendly" or "green" for both new construction and renovations. Spray polyurethane foam (SPUF) insulation has gained significant acceptance by both consumers and the construction industry due to its high R-value, which results into significant energy savings among other things. Despite its acceptance by consumers and the construction industry, consideration must be given to potential chemical exposures to applicators installing these products. This study sought to determine, through quantitative experimentation, if there was a release of glycol derivatives including, diethylene glycol (DEG), ethylene glycol (EG), and propylene glycol (PEG), during the application of SPUF. In addition, total volatile organic Compounds (tVOCs) and various environmental parameters were also collected during this research. This study utilized a two-component small-scale SPUF kit manufactured by the Dow Chemical Company, known as the FROTH-PAK™ kit. This specific kit is typically used by the construction industry to fill cavities, cracks, floor and wall penetrations, and expansion joints of buildings. In order to determine the presence of these glycol derivatives, personal breathing zone samples were collected during the application of the SPUF during three application trials. Glycols derivatives were measured using active sampling techniques. Supplementary parameters including tVOCs, ambient and wet-bulb temperature, relative humidity, carbon monoxide, and carbon dioxide, were measured using direct-reading techniques. During this study several modifications were made to the work area and the air sampling methodology to assist in verifying the presence of the glycols and the conditions in which they may be present in the air during the application of SPUF insulation. All samples were sent to an accredited laboratory and were analyzed by the Nation Institute of Occupational Safety and Health Method 5523. During this study, measurable amounts of diethylene glycol and propylene glycol were detected in two of the trials in which no ventilation in the work area was utilized. During one trial in which a work area ventilation system was utilized, none of the glycols were detected in the laboratory analysis above the limit of detection given the analytical method. Ethylene glycol was not detected in any of the samples submitted for analysis. The results for the tVOC measurements were inconclusive. Based on the results of the air sampling, it is likely that exposure to diethylene glycol and propylene glycol may occur under certain conditions. However, due to the limited number of samples and the variation between the samples collected in this study, a generation rate or concentration buildup estimate for comparison of the OELs was not conducted. These conditions include the quantity of ventilation used during application, the application duration, and proper operation of the SPUF application equipment. Based on the results, there is evidence that additional research may be needed in this area.

Cigarette butts are rapidly accumulating on our planet; trillions of them are discarded every year. In this paper, I examine why cigarette litter is a problem. I first discuss the biodegradability of filters and its scientific basis, including ways to enhance degradation rates by chemically manipulating filters. I also talk about the persistence of cigarette chemicals and their potential toxic effects on children and animals. I consider other social, economic, and environmental consequences of cigarette filters and chemicals. Furthermore, I discuss various solutions smokers and non-smokers alike have created to address the problem of cigarette litter; these methods come from a wide range of artistic, science-based, and policy-based perspectives. Finally, my thesis examines this issue in the context of a college campus – Pomona College in Claremont, CA. I discuss a map showing the number of cigarette litter around buildings and sidewalks on campus and consider factors that influence the location and high counts of litter. Finally, I make recommendations for the college based on my findings.

This study examined United States Environmental Protection Agency (US EPA) methods 507 and 508.1; analytical methods used to test drinking water for Atrazine. Additionally, this study examines the seasonal variation of Atrazine in Kentucky drinking water. Atrazine is a triazine herbicide used to control and inhibit the growth of broad leaf and grassy weeds. Atrazine’s ability to be transported to community drinking water supplies makes it a significant public health issue, as it has been linked to myriad negative health endpoints ranging from endocrine disruption to various forms of cancer, including stomach and ovarian cancer. To date, there is little research examining the current methods used to test for Atrazine and its seasonal variation in drinking water. Drinking water samples previously collected by the Kentucky Division of Water and the Kentucky Geological Survey from 117 of 120 counties throughout the state from January 2000 to December 2008 were used for this study. To examine inter-method comparison between methods 507 and 508.1, samples were subjected to the Mann-Whitney U test. Median values of methods 507 and 508.1 were found to be similar (p=0.7421). To examine seasonal variation, data from each year from 2000 to 2008, as well as the entire 2000-2008 period, were analyzed using the Kruskal-Wallis One Way Analysis of Variance. Years 2000, 2002, 2003, 2004, 2007, and 2008 as well as the full 2000-2008 span were found to have significantly different Atrazine concentrations from season to season. Years 2001, 2005, and 2006 were not found to have significantly different concentrations from season to season. The 2000-2008 span was then subjected to the Seasonal Kendal Test for Trend, which determined a significant (p=0.000092) decreasing linear trend of -7.6 x 10-6 mg/L/year of Atrazine in Kentucky. Similar decreasing linear trends were seen throughout the five regions in the state during this time period as well. This study further expands on knowledge of the occurrence and persistence of Atrazine in the environment. Comparative analysis of US EPA analytical methods and the seasonal variation of Atrazine in drinking water provide a background for future research.

Foodborne illness continues to be a substantial public health issue in the United States, with fresh produce being one of the leading causes of outbreaks. Understanding routes of contamination of fresh produce and how pathogens survive on plant surfaces is paramount in improving food safety and reducing risk to public health. The objectives of this study were to select environmental E.coli isolates as pathogen surrogates of Salmonella typhimurium and E.coli O157:H7, assess lettuce plant contamination by spray irrigation water, and evaluate a common industry quality control (QC) E.coli strain (ATCC 25922). Selections of E.coli surrogates were made utilizing biofilm and leaf attachment data from lab scale assays. Five surrogates were found to be similar in biofilm formation and leaf attachment capabilities of the pathogens, while the common QC strain was significantly different than Salmonella in both biofilm formation and leaf attachment (p < 0.05). Persistence of surrogates, pathogens and the QC strain on lettuce plants was assessed in greenhouse scale experiments, where it was found that all isolates were above detection levels for 22 days. Die-off rates were calculated for all isolates, with the QC strain having the greatest rate of die-off in the first experiment (k = -4.52) and the second greatest in the second experiment (-2.82) while the pathogens and selected surrogates had statistically similar and lower rates of die-off. Based on this information, current policies concerning the sampling and management of irrigation waters and crops for microbial safety may be insufficient. It is recommended that sampling methods and frequencies be adjusted for irrigation waters and fresh produce, and the use of projected die-off rates not be used for the determination of time intervals needed before a crop is safe to harvest.

Phthalates are a class of ubiquitous environmental contaminants that cause health problems including reproductive disorders, asthma, and obesity. Advocacy against phthalates has been taking place in the US since the mid-1990s, and eight in-depth interviews were conducted with advocates and scientists in order to construct a history of this advocacy. There have been a variety of campaigns and victories; those around medical devices, children’s products, and personal care products are examined in detail. Phthalate exposure data for a representative sample of the US population indicates that exposure to DEP, DEHP, DnBP, and BBzP went down between 1999 and 2010. As these were the phthalates that had the largest volume of advocacy during the period researched, this decrease suggests that advocacy around specific phthalates is effective in reducing exposure and that more advocacy around phthalates, and potentially other harmful chemicals, could result in further decreased exposure and improved health in the US population. Additional research using more finely graded biomonitoring data would help deepen understanding about correlations between advocacy and phthalate exposure. In reviewing the health effects of phthalates, it was found that a disproportionate amount of the research is on male reproductive health effects, which is partially responsible for the fact that a disproportionate amount of phthalate advocacy is on heath effects relating to men, particularly male babies. Both phthalate science and advocacy sometimes treat women instrumentally, objectifying them or regarding them as incubators. To combat this, scientists could do more research on the health effects of phthalates on women and advocates could take more care not to neglect or instrumentalize women in their efforts to reduce phthalate exposure for all people.

Lyme disease is one of the most common infectious diseases present in the United States today and it is clear that the changing climate will affect the geographical range of it across the country. Climate change may impact the range of the Lyme vector species, ticks, which will in turn expand the range of human risk. Although I could not successfully map the possible spread of tick populations or Lyme disease incidence as a result of climate change, my research shows a direct connection between infected tick geographic distribution and key climatic variables, such as temperature, humidity, and precipitation. It is expected that as the climate changes, particularly as it warms, the range of suitable habitat for ticks will expand into high latitudes and altitudes. The expansion of tick populations will put previously unaffected human populations at greater risk of Lyme disease. It is essential that further research be done to confirm the possible consequences of climate change on Lyme disease in the United States and to gain a more precise understanding of how and where effects will be seen. Health officials and policymakers must be informed so they can properly educate and prepare people preemptively for potential Lyme disease outbreaks.

The United States possesses a well intentioned but misguided lunch program, leaving children overfed but malnourished. Currently, a revolution is under way to transform programs around the country by incorporating locally grown and fresh ingredients, as well as integrating hands-on educational experiences with gardening and nutrition. The Claremont Unified School District (CUSD) makes up a group of schools that once heavily relied on unhealthy processed foods for providing lunch. Through a series of modifications in the past three years, CUSD’s program has been remodeled to feature more local produce and fresh ingredients, independent of USDA commodities or large scale agriculture. This has led to a healthier student body as well as a more cohesive school community.

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