Field measurement on the emissions of PM, OC, EC and PAHs from indoor crop straw burning in rural China.

Field measurements were conducted to measure emission factors of particulate matter (EFPM), organic carbon (EFOC), elemental carbon (EFEC), 28 parent polycyclic aromatic hydrocarbons (EF28pPAHs), and 4 oxygenated PAHs (EF4oPAHs) for four types of crop straws burned in two stoves with similar structure but different ages. The average EFPM, EFOC, EFEC, EF28pPAHs, and EF4oPAHs were 9.1 ± 5.7 (1.8-22 as range), 2.6 ± 2.9 (0.30-12), 1.1 ± 1.2 (0.086-5.5), 0.26 ± 0.19 (0.076-0.96), 0.011 ± 0.14 (1.3 × 10(-4) - 0.063) g/kg, respectively. Much high EF28pPAHs was observed in field compared with the laboratory derived EFs and significant difference in EF28pPAHs was identified among different crop residues, indicating considerable underestimation when laboratory derived EFs were used in the inventory. The field measured EFPM, EFOC, and EFEC were significantly affected by stove age and the EFs of carbonaceous particles for the 15-year old stove were approximately 2.5 times of those for the 1-year old stove.