Date(s) - 2017/05/26
12:30 pm - 1:30 pm
Speaker: Dr. Curtis Noonan (About)
The global burden of disease attributed to household air pollution is primarily driven by exposures to smoke from burning of biomass fuels for cooking and heating in developing countries. However, wood-burning is also an importance source of ambient and household air pollution in developed countries, particularly in rural communities. Intervention strategies for reducing the health burden from exposure to biomass combustion smoke in developed countries include community-level and household-level approaches, but contemporaneous evaluations of health impacts following these intervention strategies have been limited. We review here a selection of such studies, ranging from natural experiments to controlled experiments. Two natural experiment studies tracked population-level health outcomes during community-wide strategies to reduce ambient biomass combustion exposures. In the small rural community of Libby, Montana, USA over 1,100 woodstoves were replaced predominantly with improved technology wood burning heaters. A four year survey-based study tracked parent reported respiratory symptoms and conditions among school children, showing significant percent reductions in reported frequency per 5 µm/m3 reduction in ambient PM2.5 for wheeze (27%), cold (25%), bronchitis (55%), flu (52%), and throat infection (45%). In Launceston, Tasmania, Australia substantial mortality changes were observed from the period before (1994-2000) and after (2001-07) the government-coordinated fuel switching effort. Investigators demonstrated significant reductions in male, but not female, mortality. Two controlled experimental trials tracked individual health outcomes following household-level interventions. A filter intervention crossover study examined changes in microvascular endothelial function as measured by reactive hyperemia index (RHI) as well as changes in serum and urine markers of oxidative stress and inflammation. The use of the filter was associated with significantly higher mean percent measures of RHI (9.4%) and significantly lower mean percent measures of the inflammatory marker C-reactive protein (32.6%). Finally, a randomized trial of filter interventions compared to placebo control was conducted among children with asthma living in a woodstove home. No improvements in quality of life measures were observed, but the intervention group did show improvements in diurnal peak flow variability, an indicator of airway hyper-reactivity. Collectively, these studies demonstrate some beneficial health effects following wood stove interventions, but these investigations are few and varied with remaining questions and no repeat observation for any particular outcome or approach.
You can attend this event either online or at NIWA, Auckland.
The webinar will be live and will be followed by a brief Q&A session.
The link for the recording will be available soon!