Extended Analysis of Harvard Six Cities Study Shows Decline in Pollution Leads to Reduction in Death
In 1993, the results of the landmark Harvard Six Cities cohort study were published reporting an association between long-term exposures to particulate air pollution and premature deaths. Now, researchers have extended the mortality follow-up in this study by eight additional years, during a period of reduced air pollution concentrations.
Using estimates of pollution levels derived from ambient monitors, they found that reductions in death rates followed reductions in PM2.5 levels, including to concentrations below the current annual average standard of 15 µg/m3. Total mortality and deaths from lung cancer and cardiovascular causes were all positively associated with PM2.5 concentrations. Reduction is risk was observed for deaths due to cardiovascular and respiratory disease, and not from lung cancer, a disease with a longer latency period and less reversibility.
Laden F, Schwartz J, Speizer FE, Dockery DW. Reduction in Fine Particulate Air Pollution and Mortality: Extended Follow-up of the Harvard Six Cities Study. Am J Respir Crit Care Med 2006; Published online January 19, 2006 as doi:10.1164/rccm.200503-443OC.
For a copy of the abstract click here.
