Children can begin being tested at age 1 and should continue to be tested until they are 6 years old. Children under the age of 6 are especially at risk, and the long-term effects of lead in a child can be severe. They include learning disabilities, decreased growth, hyperactivity, impaired hearing, behavioral problems, seizures, coma, brain damage, and even death. The major source of lead exposure among U.S. children is lead-based paint and lead-contaminated dust found in deteriorating buildings. Children living in or below the poverty line, or in older housing, are also at a greater risk. If you are pregnant, avoid exposing yourself to lead. Lead can pass through you body to your baby. Although the natural level of lead in children is zero, it is considered normal to have a blood level of less than 9. If a child has recently ingested lead paint, glazes, or a lead weight, he'll need to undergo decontamination until it is removed from his body. See the section under treatment for more information.