Over half a million kids in the U.S. have high lead levels, CDC reported. The agency had lowered the threshold for lead poisoning last year to 5 mcg/dL.

According to Medline Pus, symptoms of lead poisoning include abdominal pain, aggressive behavior, headaches, irritability, reduced sensations and low appetite. At higher levels, lead poisoning can be fatal.

Data for the latest report from the agency came from the National Health and Nutrition Examination Survey (NHANES) from the periods 1999-2002 and 2007-2010.

The survey results showed that an estimated 535,000 children in the U.S. aged between 1 and 5 years had high levels of lead in their body.

Exposure to lead is common and preventable, says Centers for Disease Control and Prevention. According to the agency, lead based paint and dust are the common sources of lead exposure. Kids under 6 years of age must not be allowed near peeling walls or chewable surfaces that may have lead-based paints. In May this year, CDC lowered the recommended lead levels from 10 micrograms per deciliter to 5 micrograms.

Health records have shown that lead levels were high in children during the 70s, with an estimated 88 percent children having more than 10 µg/dL. This percent fell sharply in the period of 1991-1994 with just 4.4 percent, and 0.8 during 2007-2010.

Though there has been a substantial decline in the number of children having high lead levels, the problem still persists, with one in 38 children being affected by lead poisoning. Last year's budgeting cuts have resulted in many kids being overlooked. David Rosner, a Columbia University public health historian, called the budget-cuts "an abandonment of children."

"We've been acting like the problem was solved and this was a thing of the past," he added, reports Counsel & Heal.