The finding that lead is prevalent in soils, especially in urban areas, is no news to Ruth Ann Norton, executive director of the Coalition to End Childhood Lead Poisoning, based in Baltimore.

"Urban soil is an important source of lead," she said. But she added that housing still tops the list for lead exposure due to old lead-based paints. Numerous products that used lead as a stabilizer, such as furniture, old mini-blinds, old paint and old costume jewelry, may still be in people's homes, she added.

Some tips on avoiding or removing lead:

• Repair chipping paint, especially old paint. "If you live in an older home (pre-1978), and you have chipping peeling or flaking, you want to repair that safely," she said. That means not dry scraping but wet scraping -- and probably getting professional advice if you decide to do it yourself.
• Know that a little lead can go a long way. "A lead chip the size of a nickel, if broken down, could contaminate a 3,000-square-foot house," Norton said.
• Minimize exposure, especially if you live in an older neighborhood that's likely to have lead in the soil. "Leave your shoes at the door," she said. "Have a welcome mat you can wash off."