NC clean air law saved lives, study finds

North Carolina’s 2002 crackdown on power plant emissions may have saved 1,700 lives a decade later, UNC Chapel Hill researchers say.

The Clean Smokestacks Act, adopted in 2002, was aimed at pollutants billowing from coal-fired power plants. Power plants are major sources of the fine sulfate particles the study targeted.

By 2012, the UNC research shows, the risk of premature death from the particles had dropped 63 percent – preventing an estimated 1,700 deaths in the state.

UNC doctoral student Ya-Ru Li and her adviser, associate professor of environmental engineering Jacqueline MacDonald Gibson, wrote the paper. It appeared in the print edition of the journal Environmental Science & Technology this week.

Other research has looked nationally at the health effects of air pollutants. The UNC study focused on North Carolina, Gibson said, comparing it to surrounding states without similar air-quality initiatives.

The findings were unexpectedly strong, she added. “We really do believe that this shows that policy can have real results.”

The U.S. Supreme Court recently upheld a federal law, the Cross-State Air Pollution Rule, that limits power-plant emissions that form fine particles or the irritating gas ozone.

The Clean Smokestacks Act slashed power-plant emissions of nitrogen oxide and sulfur dioxide, which form fine particles. Duke Energy’s 14 coal-fired plants exceeded the targeted reductions for both ahead of 2009 and 2013 deadlines.

In January, the N.C. Department of Environment and Natural Resources sued the Environmental Protection Agency over fine-particle regulations. DENR argued the EPA ignored the reductions the state has achieved.

The UNC study is the second in recent months to link stronger emission standards to improved health.

In June, Duke University scientists reported a substantial decline in deaths from asthma and emphysema as North Carolina tightened air standards under Clean Smokestacks and federal laws.

Despite that link, the Duke researchers cautioned that other factors such as medical histories or allergies could also help explain the trend.

Gibson acknowledged that it’s hard to tease out the role air pollutants play in premature deaths.

“There’s really no controversy that particulate matter is bad for your health,” she said. “It’s just the magnitude of the risk that’s in dispute.”

Fine particles form in the air when combustion gases undergo chemical changes. Inhaled, the particles work deep into the lungs. EPA estimates that one out of three people are at risk of health problems from particles.

Catawba, Davidson and Guilford counties were ruled in compliance with the federal fine-particle standard in 2011. No other N.C. counties violate the standard.