Evaluation of mass and surface area concentration of particle emissions and development of emissions indices for cookstoves in rural India.

Mass-based dose parameters (for example, PM(2.5)) are most often used to characterize cookstove particulate matter emissions. Particle surface area deposition in the tracheobronchial (TB) and alveolar (A) regions of the human lung is also an important metric with respect to health effects, though very little research has investigated this dose parameter for cookstove emissions. Field sampling of cookstove emissions was performed in two regions of rural India, wherein PM(2.5), particulate surface area concentration in both TB and A regions, and carbon monoxide (CO) were measured in 120 households and two roadside restaurants. Novel indices were developed and used to compare the emissions and efficiency of several types of household and commercial cookstoves, as well as to compare mass-based (PM(2.5)) and surface area-based measurements of particle concentration. The correlation between PM(2.5) and surface area concentration was low to moderate: Pearson's correlation coefficient (R) for PM(2.5) vs surface area concentration in TB region is 0.38 and for PM(2.5) vs surface area concentration in A region is 0.47, indicating that PM(2.5) is not a sufficient proxy for particle surface area concentration. The indices will also help communicate results of cookstove studies to decision makers more easily.