As many as 24,000 deaths annually in California are linked to chronic exposure to fine particulate pollution, triple the previous official estimate of 8,200, according to state researchers. The revised figures are based on a review of new research across the nation about the hazards posed by microscopic particles, which sink deep into the lungs.
"Our report concludes these particles are 70% more dangerous than previously thought, based on several major studies that have occurred in the last five years," said Bart Croes, chief researcher for the California Air Resources Board. Croes will present his findings at a board meeting in Fresno this morning.
The studies, including one by USC tracking 23,000 people in greater Los Angeles, and another by the American Cancer Society monitoring 300,000 people across the United States, have found rates of heart attacks, strokes and other serious disease increase exponentially after exposure to even slightly higher amounts of metal or dust. It is difficult to attribute individual deaths to particulate pollution, Croes conceded, but he said long-term studies that account for smoking, obesity and other risks have increasingly zeroed in on fine particulate pollution as a killer.
What are the primary sources of fine particulate pollution? According to the World Health Organization:
"Short-term epidemiological studies suggest that a number of source types are associated with health effects, especially motor vehicle emissions, and also coal combustion. These sources produce primary as well as secondary particles, both of which have been associated with adverse health effects. One European cohort study focused on traffic-related air pollution specifically, and suggested the importance of this source of PM. Toxicological studies have shown that particles originating from internal combustion engines, coal burning, residual oil combustion and wood burning have strong inflammatory potential.
Translation: we now have even more compelling health reasons to reduce vehicle-miles traveled by car and not build any new coal-fired power plants in Iowa.
The Iowa Department of Natural Resources has more information about fine particulate levels in our state.