Navajo Coal Combustion and Respiratory Health Near Shiprock, New Mexico

Abstract

Indoor air pollution has been identified as a major risk factor for acute and chronic respiratory diseases throughout the world. In the sovereign Navajo Nation, an American Indian reservation located in the Four Corners area of the USA, people burn coal in their homes for heat. To explore whether/how indoor coal combustion might contribute to poor respiratory health of residents, this study examined respiratory health data, identified household risk factors such as fuel and stove type and use, analyzed samples of locally used coal, and measured and characterized fine particulate airborne matter inside selected homes. In twenty-five percent of homes surveyed coal was burned in stoves not designed for that fuel, and indoor air quality was frequently found to be of a level to raise concerns. The average winter 24-hour PM2.5 concentration in 20 homes was 36.0 μg/m3. This is the first time that PM2.5 has been quantified and characterized inside Navajo reservation residents' homes.

Patterns and predictors of personal exposure to indoor air pollution from biomass combustion among women and children in rural China

“…Instead, much of the published epidemiologic work assessed exposure using crude proxies such as fuel and stove type (Johnson and Aderele, 1992;Mishra, 2003;Mishra et al, 1999;Morris et al, 1990;Sharma et al, 1998;Victora et al, 1994). Health studies with direct pollution measurements have substituted cooking area PM for personal PM exposure (Albalak et al, 1999;Bunnell et al, 2010;Liu et al, 2007;Mengersen et al, 2011;Robin et al, 1996) or combined area PM measurements with the time spent in different microenvironments to approximate personal exposure (Bautista et al, 2009;Ezzati et al, 2000). Several IAP exposure assessment studies used personal carbon monoxide exposure as a proxy for personal PM exposure (Dionisio et al, 2008;Naeher et al, 2001).…”

Estimating the Number of Low-Income Americans Exposed to Household Air Pollution from Burning Solid Fuels

“…The search revealed only a few studies that documented indoor air quality in U.S.-based homes using solid fuels as a primary heating source (Bunnell et al 2010; Noonan et al 2012a; Paulin et al 2013; Robin et al 1996; Ward et al 2008, 2011). For each study, we attempted to determine the percentage of homes whose 24-hr average for PM 2.5 (particulate matter with diameter ≤ 2.5 μm) exceeded the WHO recommended level of 25 μg/m 3 (WHO 2005).…”

Emission factors of fine particulate matter, organic and elemental carbon, carbon monoxide, and carbon dioxide for four solid fuels commonly used in residential heating by the U.S. Navajo Nation

“…Wood is affordable, widely available within the reservation, and culturally significant to the Navajo (Champion et al, 2017). High-volatile bituminous coal (Kirschbaum and Biewick, 2000) is provided at no cost to residents near mines (Hickmott et al, 1997;Bunnell et al, 2010). Many Navajo homes burn wood and coal in combination using homestoves (i.e., residential noncatalytic wood stoves) that are old and/or leaky (Bunnell et al, 2010), impacting indoor air quality in many Navajo homes.…”

“…High-volatile bituminous coal (Kirschbaum and Biewick, 2000) is provided at no cost to residents near mines (Hickmott et al, 1997;Bunnell et al, 2010). Many Navajo homes burn wood and coal in combination using homestoves (i.e., residential noncatalytic wood stoves) that are old and/or leaky (Bunnell et al, 2010), impacting indoor air quality in many Navajo homes. Bunnell et al (2010) found that 19 coal-burning homes in Shiprock, New Mexico, had a mean indoor 24-hr fine particulate matter (aerodynamic diameter ≤2.5 μm; PM 2.5 ) concentration much higher than one propane-burning home studied (38 vs. 0.29 µg/m 3 ).…”

“…Many Navajo homes burn wood and coal in combination using homestoves (i.e., residential noncatalytic wood stoves) that are old and/or leaky (Bunnell et al, 2010), impacting indoor air quality in many Navajo homes. Bunnell et al (2010) found that 19 coal-burning homes in Shiprock, New Mexico, had a mean indoor 24-hr fine particulate matter (aerodynamic diameter ≤2.5 μm; PM 2.5 ) concentration much higher than one propane-burning home studied (38 vs. 0.29 µg/m 3 ). Previously, Robin et al (1996) reported higher median PM 10 concentrations in wood-burning Navajo homes compared with homes that used gas or electric heating (101 vs. 22 µg/m 3 ).…”