ATLANTA (AP) - For the first time in 20 years, U.S. health officials have lowered the threshold for lead poisoning in young children.
    
The change means many more children could be diagnosed with high levels of lead in their blood.

Too much lead is harmful to developing brains and can mean a lower IQ.
    
Recent research persuaded government officials that children under 6 could be harmed from lead levels lower than the old standard.

Most youngsters get it from paint chips or dust in older homes with lead paint.
    
The Centers for Disease Control and Prevention announced the change Wednesday.

At the same time, CDC officials said they don't have more money to help doctors or local health departments test children or figure out the source of any lead contamination.