Levels of PM₂.₅/PM₁₀ and associated metal(loid)s in rural households of Henan Province, China

Although a majority of China's rural residents use solid fuels (biomass and coal) for household cooking and heating, clean energy such as electricity and liquid petroleum gas is becoming more popular in the rural area. Unfortunately, both solid fuels and clean energy could result in indoor air pollution. Daily respirable particulate matter (PM ≤ 10 μm) and inhalable particulate matter (PM ≤ 2.5 μm) were investigated in kitchens, sitting rooms and outdoor area in rural Henan during autumn (Sep to Oct 2012) and winter (Jan 2013). The results showed that PM (PM₂.₅ and PM₁₀) and associated metal(loid)s varied among the two seasons and the four types of domestic energy used. Mean concentrations of PM₂.₅ and PM₁₀ in kitchens during winter were 59.2–140.4% and 30.5–145.1% higher than those during autumn, respectively. Similar with the trends of PM₂.₅ and PM₁₀, concentrations of As, Pb, Zn, Cd, Cu, Ni and Mn in household PM₂.₅ and PM₁₀ were apparently higher in winter than those in autumn. The highest mean concentrations of PM₂.₅ and PM₁₀ (368.5 and 588.7 μg m⁻³) were recorded in sitting rooms in Baofeng during winter, which were 5.7 and 3.9 times of corresponding health based guidelines for PM₂.₅ and PM₁₀, respectively. Using coal can result in severe indoor air pollutants including PM and associated metal(loid)s compared with using crop residues, electricity and gas in rural Henan Province. Rural residents' exposure to PM₂.₅ and PM₁₀ would be roughly reduced by 13.5–22.2% and 8.9–37.7% via replacing coal or crop residues with electricity. The present study suggested that increased use of electricity as domestic energy would effectively improve indoor air quality in rural China. Copyright © 2015 Elsevier B.V.