Briefs: Is air conditioning good for health?

Air conditioning (AC) could blunt the ill effects of air pollution, according to a recent study by Bell et al. from Yale University, published in Epidemiology in September 2009. The study investigated the short-term effects of particulate matter (PM) on mortality and cardiovascular or respiratory hospitalizations, comparing various AC prevalence levels. It showed that higher AC prevalence had lower PM effects as each additional 20% of households with central AC was associated with a 43% decrease in PM effects on cardiovascular hospitalization. However, Dr Sverre Vedal of the University of Washington School of Public Health notes that analysing the long-term effects of air conditioning (strongly linked to window closing) for individuals might be more useful than looking at communities as a whole. The current findings, he notes, could be blurred by the effects of other factors such as temperature, humidity, etc. on pollutants and health. Bell concluded "As scientists study how climate change may affect human health, understanding how air conditioning affects health, both positively and negatively, will be critically important, especially as air conditioning use continues to grow.