Cave dwelling is an ancient and unique type of residence in the Loess Plateau of Northern China, where the economics are less-developed. The majority of the local dwellers rely on traditional solid fuels for cooking and heating, which can emit large amounts of particles into both indoor and outdoor environments. In this study, we measured the real-time household concentrations of PM2.5 and explored the association between personal daily PM2.5 exposure and blood pressure (BP). Cooking and heating activities with different energies made a great variation in the household PM2.5 air pollution, and residents using biomass had the highest personal PM2.5 exposure. Temperature and relative humidity are both significantly linear correlated with household PM2.5 air pollution. Besides, systolic blood pressure (SBP) was demonstrated to be positively associated with personal PM2.5 exposure: with each 10-μg/m3 incremental PM2.5 concentration when controlling all the other factors, SBP will increase by 0.36 mmHg (95% confident interval (CI) 0.05-0.0.77 mmHg). If solid fuels could be replaced with clean energies, personal PM2.5 exposure and SBP would reduce by more than 21% and 3.7%, respectively, calling for efficient intervention programs to mitigate household air pollution of cave dwellings and protect health of those residents.
Keywords: Blood pressure; Cave dwellings; Energy type; Indoor and outdoor air; PM2.5 exposure; Rural areas.