Researchers at Duke University have found that death rates from emphysema, asthma and pneumonia have gone down since national and state air pollution controls went into effect in the early 1990s.
Using mortality trends from state public health data, along with monthly measurements from air-monitoring stations across North Carolina from 1993-2010, the researchers found a close connection between improved air quality and declining death rates from respiratory illnesses.
“This research tends to show that environmental policies work, if the goal of those policies is not only to improve the environment, but also to improve health,” said H. Kim Lyerly, M.D., a Duke professor.
The researchers analysed a 17-year period after a variety of federal air pollution measures were adopted. Among others, national requirements lowered emissions from car engines, chemical plants and coal-fired power plants, and also targeted emissions that contributed to acid rain and depletion of the ozone layer. North Carolina also enacted the Clean Smokestacks Act in 2002 to reduce emissions from coal-fired power plants.
Using the public health and environmental monitoring data, and controlling for factors such as lower smoking rates and month-to-month fluctuations in air quality, the researchers calculated that each one-unit reduction in the air pollution components coincided with a drop in deaths from emphysema, asthma and pneumonia.
In particular, reduced levels of sulphur dioxide showed a strong correlation to lower death rates for emphysema, asthma and pneumonia; decreases in carbon monoxide were associated with lower emphysema and asthma deaths. Fine particulates coincided with lower emphysema death rates, and reductions in a second particulate matter were associated with lower asthma deaths.
Photo Credit: Stefano Corso /Creative Commons
