MEDICAL GEOLOGY IN THE NAVAJO NATION: ASSESSING THE HEALTH EFFECTS OF BURNING COAL

The purpose of this study is to assess the relative contributions to respiratory ailments in the Navajo Nation (such as asthma, chronic obstructive pulmonary disorder, and upper respiratory tract infections) that result from exposure to indoor coal smoke and outdoor air pollution from nearby industrial coal combustion. This project addresses issues in medical geology, human health, and environmental quality related to the occurrence, extraction, transport, utilization, and disposal of coal, the major energy resource in the Navajo Nation. Fossil fuels contain potentially toxic substances that may affect human health and environmental quality. Potential health impacts of emissions from power plants in the Shiprock area of the Navajo Nation and indoor burning of coal in stoves by Navajo Nation residents will be examined. Source material (coal), fly ash, and fine particulate matter 2.5 microns or smaller (PM 2.5) have been collected and analyzed by ICP/MS, AAS, SEM, and GC/MS to characterize the inorganic and organic matter associated with the particles and their likely sources. Since 2002, US EPA has regulated ambient PM 2.5 concentrations because this fraction poses the greatest risk to human health. This study represents the first quantification and characterization of ambient and indoor PM 2.5 in the Navajo Nation. The spatial distribution of the analytical results will be correlated with known disease occurrences using GIS. Groups participating in this multidisciplinary, multi-agency research project include the USGS, US EPA, George Washington University, DOE, CDC, Tribal College Initiative, Navajo EPA, and the Indian Health Service.