AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Linking Cookstove Emissions to Indoor Air Quality: Outcome of a Multi-year Cookstove Intervention Trial in Rural India
MOHAMMAD MAKSIMUL ISLAM, Roshan Wathore, Grishma Jain, Karthik Sethuraman, Hisham Zerriffi, Julian Marshall, Rob Bailis, Andrew Grieshop, North Carolina State University
Abstract Number: 583 Working Group: Biomass Combustion: Emissions, Chemistry, Air Quality, Climate, and Human Health
Abstract Combustion of biomass in residential cookstoves is a major source of household air pollution, an acknowledged threat to human health. In this study, we assess indoor PM2.5 and its variability during a cookstove intervention trial in which multiple stoves were offered to households in two rural areas in India (Kullu in Himachal Pradesh; Koppal in Karnataka). We also aim to improve links between estimates of cookstove emissions and indoor PM2.5. The study had three ~3-month-long measurement periods (baseline, follow-up-1, follow-up-2) in each location. We measured real-time and gravimetric indoor PM2.5 concentrations during ~5000 cooking events of traditional and alternate biomass and modern-fuel stoves. We also conducted simultaneous emission measurements for a subset of those cooking events.
Intention-to-treat analysis in Koppal showed significant reduction in indoor PM2.5 in intervention households relative to control households only in follow-up-1, indicating mixed effectiveness. Black carbon concentrations showed significantly different distributions in different seasons. In general, Kullu households had ~50% lower PM2.5 concentration than Koppal, strong evidence of inter-site variability in PM2.5. Higher estimated air exchange rate (AER; 11±5 h-1) and lower cooking time (3.6±2.9 h) in Kullu households compared to Koppal (7±4 h-1 and 5.3±3.0 h) may explain the reduced PM2.5 concentration in Kullu. Households in Kullu and Koppal having LPG had median PM2.5 concentrations of 91 and 111 µg/m³ respectively, 1.5-2 times lower than households without LPG. In Koppal, PM2.5 concentrations were 1.5-2.5 times higher in households without chimneys than those with chimneys. We will apply mixed effect modeling using seasons, locations, AER, household ventilation characteristics (e.g. presence of chimney, doors and windows), stove types, fuel use, and presence of other emission sources (e.g. incense, lamp) as predictors to identify the factors contributing to indoor PM2.5 variability. Finally, we will develop a statistical model linking measured emissions rates and PM2.5 concentrations.