Indoor particulate matter in rural, wood stove heated homes

Abstract

Ambient particulate matter (PM) exposures have adverse impacts on public health, but research evaluating indoor PM concentrations in rural homes in the United States using wood as fuel for heating is limited. Our objectives were to characterize indoor PM mass and particle number concentrations (PNCs), quantify infiltration of outdoor PM into the indoor environment, and investigate potential predictors of concentrations and infiltration in 96 homes in the northwestern US and Alaska using wood stoves as the primary source of heating. During two forty-eight hour sampling periods during the pre-intervention winter of a randomized trial, we assessed PM mass (< 2.5 μm) and PNCs (particles/cm3) in six size fractions (0.30–0.49, 0.50–0.99, 1.00–2.49, 2.5–5.0, 5.0–10.0, 10.0+ μm). Daily mean (sd) PM2.5 concentrations were 28.8 (28.5) μg/m3 during the first sampling period and 29.1 (30.1) μg/m3 during the second period. In repeated measures analyses, household income was inversely associated with PM2.5 and smaller size fraction PNCs, in particular. Time of day was a significant predictor of indoor and outdoor PM2.5 concentrations, and infiltration efficiency was relatively low (Finf (sd) = 0.27 (0.20)). Our findings demonstrate relatively high mean PM concentrations in these wood burning homes and suggest potential targets for interventions for improving indoor air quality and health in rural settings.

Impact of Biomass Home Heating, Cooking Styles, and Bread Toasting on the Indoor Air Quality at Portuguese Dwellings: A Case Study

“…A range from 6 µg·m −3 to 55 µg·m −3 was documented by these authors. A study in 50 homes (Montana, USA) [40] with wood stoves reported PM 2.5 concentrations of 32.3 ± 32.6 µg·m −3 (ranging from to 6.0 µg·m −3 to 163 µg·m −3 ) for a sampling period of 48 h. Results in the same range were obtained in a study in 96 homes (USA) [41] where, for two sampling periods, the mean daily concentrations of 28.8 ± 28.5 µg·m −3 and 29.1 ± 30.1 µg·m −3 were observed. When comparing particulate matter levels in living rooms of houses with central heating or wood heating [42], PM 10 levels were found to be six times higher in houses equipped with wood heating systems (203 ± 201 µg·m −3 ) than in dwellings with central heating.…”

Variation of Indoor Particulate Matter Concentrations and Association with Indoor/Outdoor Temperature: A Case Study in Rural Limpopo, South Africa

“…Studies conducted in rural areas have shown that the use of wood and/or coal for cooking or heating can be a significant source of particulate matter inside homes [8,9]. PM 10 in homes that use biomass fuel was found to be 10-70 times above ambient concentrations observed in some of the world's most polluted cities [10].…”

Impact of home remediation and household education on indoor air quality, respiratory visits and symptoms in Alaska Native children

“…The varied PM2.5 response across homes in our studies and others may be due to factors (e.g. household size, household activities, ventilation) other than the introduction of a new woodstove [25,27]. The recent Asthma Randomized Trial of Indoor Wood Smoke study demonstrated that air filtration units were superior (68% decrease) to woodstove change-out (no significant reductions) in reducing PM2.5 in homes; however, their effectiveness in reducing LRTIs is unknown [28].…”