Daniel Farcas

Date of Graduation

2015

Document Type

Dissertation

Degree Type

PhD

College

Davis College of Agriculture, Natural Resources and Design

Department

Agricultural and Resource Economics

Committee Chair

Alan R Collins

Committee Co-Chair

Jamison F Conley

Committee Member

Martin Harper

Committee Member

Michael A McCawley

Committee Member

Dennis K Smith

Abstract

Chapter 1. Introduction to erionite. Erionite is an emerging naturally-occurring carcinogen that through continued and frequent exposure can lead to mesothelioma. Erionite exposure is mostly environmental and it affects individuals that live in areas where a natural deposit of the mineral exists.;Chapter 2. What is mesothelioma? Why should I should be afraid? How do you calculate the risk of mesothelioma? What are the results? Mesothelioma, a rare cancer and the most dreaded asbestos-related disease affects the lining of the chest cavity and extremely debilitating and terminal. Rates of Malignant Mesothelioma (MM) are dependent on exposure times, concentrations, smoking, age of first exposure, etc. Although there is currently no proof of emerging erionite-related illnesses in the U.S., mesothelioma normally takes 30 to 50 years to develop. In this chapter, a preliminary risk assessment calculation was conducted considering time weighting factors for different activities and exposure years based on the expected age of first exposure according to EPA's excess lifetime cancer risks (ELCRs). The results show an increased probability of mesothelioma occurrence as exposure is prolonged, ranging from 2 to 26 cases in 10,000 individual exposure. This is higher than EPA's acceptability risk standard of 1:10,000.;Chapter 3. How do you find these fibers in the environment? How do you separate them? How do you identify them? What was found? Asbestos or asbestos-like fibers (erionite) may be present in trace quantities in the environment which are non-detectible with the current analytical techniques. A recent advance in technology, the Fluidized Bed Asbestos Segregator (FBAS), is enabling us to identify and measure very small concentrations of erionite and asbestos in soil. This technique effectively and efficiently separates out erionite fibers from sampled soils while maintaining the integrity of the erionite fibers. Thus, the true structural characteristics and quantity of erionite fibers in the soils can be determined. The results show that traces of erionite in the analyzed soil samples, although well below the detection limit of 1% by traditional PCM/PLM methods, were reliably detected by the FBAS method and identified by Transmission Electron Microscopy (TEM) / Scanning Electron Microscopy (SEM) analysis.;Chapter 4. Where is erionite found? How did you map its location using soil sample data? The soil samples were collected by Center for Disease Control (CDC) / National Institute for Occupational Safety and Health (NIOSH), North Dakota University, and the U.S. Forest Service (USFS) in Slim Buttes region of the Sioux Ranger District on the Custer National Forest (CNF) in Harding County, South Dakota. The spatial variation of erionite concentrations in the soil across this research area was mapped using ArcGIS 10.2 software. The results show that the typical soil concentration of erionite on the surface of erionite-hosting geological layers is significantly higher, reaching almost 23%, compared to surrounding soils where the concentration was less than 0.01%. Figure 45 presents a map the predicted priority areas for additional research and investigation into erionite concentrations.;Chapter 5. What is the purpose of risk communication? How can it be accomplished within Harding County? The purpose of this chapter is to describe potential risk communication methods that can be used to convey a general sense of the increased risk of developing mesothelioma from breathing in erionite in Harding County. All the risk calculations presented in Chapter 2 have significant uncertainties associated with them. However, these calculations show similar results, i.e. there exists an amplified risk of mesothelioma from erionite exposure in the CNF. This last chapter provides an outline for developing recommendations for a risk communication plan that could be used by the local officials to formulate and convey risk messages to the three main audiences potentially impacted by exposure to erionite on the CNF: Harding County residents, USFS workers and CNF visitors. Based on extended risk literature research, demographic and epidemiological data and risk assessment calculations from previous chapters provide a framework for dialogue between community and authorities. Demonstrations of risk assessment results are communicated through visual displays in the form of numerical data, log scale presentation, and persuasive graphic images.;General conclusions. Naturally occurring erionite is generally consider safe if it is left undisturbed and encapsulated by soil and/or vegetation. There is currently very little evidence that living above or near geology that includes mineral fibers is a hazard, although risk calculations indicate a level of concern about erionite that justifies further investigations. (Abstract shortened by UMI.).

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