The exhausting election season is finally over, but the process of governing continues. In the rhetoric-charged environment of fiscal cliffs, health care costs and taxes it is easy to lose sight of slow-moving policies that can positively impact public health. The Obama administration is poised to make an overdue change to an important air quality standard for fine particulate matter, or soot.
Particulate matter is a pollutant regulated under the landmark, bipartisan Clean Air Act, signed into law by President Nixon in 1970. Sources of particulate matter include emissions from diesel engines, coal burning and incomplete combustion of biomass material from wood stoves or wildfires.
Particulate matter is classified according to size. Fine particulate matter, also called soot, is a mixture of solid particles and liquid droplets that are microscopic in size — about 1/30 the width of a human hair. Unlike larger particles, which can be expelled with a cough or sneeze, soot can bypass these defenses and lodge deep in our lungs.
Decades of research and thousands of studies have shown that exposure to soot can result in adverse respiratory and cardiovascular outcomes, particularly in children with asthma, the elderly with chronic obstructive pulmonary disease and people with pre-existing cardiovascular conditions.
The current annual standard for acceptable average soot levels is described as 15 micrograms per cubic meter of air. For a 24-hour period the current standard for soot exposure is 35 micrograms per cubic meter of air. Why are such standards important for communities? They serve as one of several barometers for gauging community health.
When a community’s soot levels exceed these standards, local and state agencies are compelled to develop plans to address the problem and identify a pathway to cleaner air. These actions do not occur overnight but through a deliberative process that assesses various approaches and consequences.
The agency responsible for setting national air quality standards, the Environmental Protection Agency (EPA), has proposed tightening the annual exposure limit to between 12 and 13 micrograms per cubic meter of air. Will this change have any effect? Yes. One of the remarkable findings in recent years has been that when communities act to improve air quality, the public benefits.
On a national scale, urban soot levels have declined over the past few decades, largely driven by stricter emission standards on automobiles and industrial sources. A large national study demonstrated that these reductions in soot levels led to increases in life expectancy after accounting for other factors that changed with time and influence health.
On a smaller scale and close to home, in Libby we showed that a community-driven effort to reduce levels of soot from wood stove emissions was associated with a reduction in respiratory illnesses among children.
As with any proposed regulatory change, the new soot standard will likely be met with opposition from certain parties arguing that the cost of adherence to stricter standards is too great a burden. To this, I would argue that the cost of not taking such action is too great, and the EPA should consider even more rigid provisions.
Indeed, several organizations — such as the American Lung Association, American Medical Association and American Academy of Pediatrics — support a stronger annual standard of 11 micrograms per cubic meter of air as well as a stronger 24-hour standard of 25 micrograms per cubic meter of air.
The American Lung Association estimates that such soot standards would annually prevent over 35,000 premature deaths, over 23,000 hospital and emergency room visits and over 2.7 million missed days of work or school due to air pollution-caused ailments. Thus, even leaving aside the moral argument that guides communities toward protecting the health of their citizens, the anticipated savings in health care costs and productivity offer a strong positive side to any cost-based argument.
A change to this air quality standard is long overdue and is the right thing for our communities and for our economy.
Curtis W. Noonan, Ph.D., is an associate professor at the University of Montana. His laboratory investigates the human health effects of exposure to particulate matter and other airborne hazards.