Lead poisoning is totally preventable. The effects of lead poisoning are irreversible! Many children show no symptoms when they have been exposed to lead. Some symptoms like headaches, stomachache, and crankiness are often associated with other common diseases. Lead poisoning causes reduced intelligence, low attention span, reading and learning disabilities, and has been linked to juvenile delinquency, behavioral problems, and many other adverse health effects. High levels of lead can cause coma, convulsions, and death.