Given the perceived importance of winter space
heating in PM pollution exposure, it may seem
counterintuitive that our regression results failed to
find a significant effect for primary space heating fuel
on personal exposure. However, resolving the effect of
heating fuel on personal exposure in this region would
be difficult. In contrast to northern China where
heating fuel dominates domestic fuel consumption
in winter, cooking fuel may be the most important
source of exposure in the temperate climate of
Yunnan. Individuals typically spend more time in
the kitchen during winter when biomass combustion
for cooking indirectly serves as a space heater. Thus,
any reduction in exposure from use of wood-charcoal
as a primary heating fuel may be dominated by
cooking fuel use. Future IAP studies in regions with
space heating would benefit from the inclusion of
time-activity budgets to better estimate the relative
contribution of heating vs. cooking to personal
exposure.
Similarly, neither secondary cooking fuel nor envi