State air quality officials are urging Iowans not to burn leaves this fall. Brian Button, an air quality specialist for the Department of Natural Resources, says he and other state officials favor cleaner, safer disposal methods like composting or municipal curb-side pick-up. Button says the dense smoke from burning leaves is made up of microscopic soot particles that are known to trigger asthmatic attacks. He says the soot can also pose a risk to people with heart and respiratory problems. There’s carbon monoxide and toxins in the smoke, too. Button doesn’t know how many Iowa cities and towns allow leaf burning.Button says the D-N-R is issuing a general caution against open burning because of air quality concerns, as well as the danger of the fire itself.Button says there have been reports in Iowa of piles of leaves burning out of control and damaging property. And he says just this year an elderly man on the east coast suffered severe burns from a burning leaf pile.