An ad campaign starts today on radio stations statewide which urges Iowans not to burn leaves. The annual rite of fall for some people can be hazardous to the health of many others, according to Brian Button, an air quality specialist at the Iowa Department of Natural Resources. Button says there are many Iowans who’re concerned about asthma.Button the goals of the ad campaign are to focus people’s attention on the dangers of leaf and garbage burning and make them think about “cleaner disposal options.”Button says burning leaves and garbage releases all sorts of toxins into the air which can aggravate health problems for people who have breathing trouble. He says leaf burning is illegal in some Iowa cities and counties.The 40-thousand dollar ad campaign will run through October. It was paid for by various federal and private grants, not state money.