Updated at 6:30 p.m. to add information on mercury pollution.
A new report released today puts both Missouri and Illinois among the top 20 states with the most toxic air pollution from power plants.
The Natural Resources Defense Council report ranked Missouri 15th and Illinois 16th nationwide, based on 2010 data from the Environmental Protection Agency, the most recent data available.
Although their relative rankings changed little from the year before, the NRDC's clean air director John Walke says both states actually reduced their emissions.
"That reflects a 20 percent drop in power plants' toxic pollution in Missouri, and a 16 percent reduction from that sector in Illinois," Walke said. "So those are impressive reductions." About a million pounds less air pollution in each state.
Walke says that’s also good news for our region’s water and fish, which are contaminated with mercury – a power plant pollutant.
“It builds up in water bodies through a process called bioaccumulation, but once you reduce it, you can actually see a pretty substantial recovery.”
Exposure to mercury can cause developmental problems - pregnant women and children are most at risk.
The U.S. EPA set limits on mercury emissions from power plants late last year, but they won’t go into effect until at least 2015.
Walke says that nationally, air pollution from the electric sector has dropped as plants have installed pollution controls or switched from coal to natural gas.
Missouri still gets more than 80 percent of its electricity from coal; Illinois gets close to half of its energy from nuclear power.
Follow Véronique LaCapra on Twitter: @KWMUScience