Characterizing household air pollutant concentrations associated with an electrification program in the rural San Joaquin Valley

TL;DR

This study found that switching to electric stoves in rural low-income homes significantly reduces indoor nitrogen dioxide levels, improving air quality and potentially reducing health risks.

Contribution

The study provides new evidence on the health benefits of electrification in rural, low-income communities, an understudied population.

Findings

Electric stove homes had 63% lower median indoor NO2 concentrations compared to gas stove homes.

Shorter monitoring durations (2-4 days for NO2, one week for PM2.5) provided reliable estimates of indoor air quality.

PM2.5 concentrations were similar across electric and gas stove homes, indicating food-related emissions dominate.

Abstract

Indoor nitrogen dioxide (NO2) and fine particulate matter (PM2.5) are concerns in U.S. households, especially those that cook using gas or propane stoves. Exposures to these and other indoor pollutants are linked to a variety of adverse health outcomes, including asthma morbidity, that disproportionately affect low-income households. We conducted a cross-sectional study of 138 homes in four low-income rural communities in California’s San Joaquin Valley, comparing air pollutant concentrations between households that participated in a state electrification program and households using propane or natural gas for cooking. In each home, pollutants were monitored for approximately one month using personal air monitors and for 48 h using reference-grade instruments. Median 48-h average indoor NO2 concentrations were 63% lower in electric stove homes (electric: 6.0 ppb, gas: 16.0 ppb, p < 0.001). No electric stove homes had 48-h indoor NO2 concentrations exceeding the California annual guideline of 30 ppb, while 17% of gas homes did. Additionally, no electric stove homes had 1-h rolling-average NO2 concentrations exceeding the 100-ppb level deemed unhealthy for sensitive groups by the U.S. Environmental Protection Agency, whereas 41% of gas homes exceeded this threshold. PM2.5 concentrations were similar across groups, indicating that cooking-related emissions from food were the dominant contributor to PM2.5 mass concentrations rather than particles generated from gas combustion. Our evaluation of monitoring durations showed that two to four days of NO2 data and one week of PM2.5 data provided reliable estimates of longer-term averages, suggesting that shorter campaigns may yield robust estimates of indoor air quality. These results support the provision of electric cooking technologies as a strategy to address air quality-related health risks in rural, low-income communities and provide new evidence from an understudied population that can inform future indoor air quality research and energy transition policies.

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