Lead poisoning is a serious and potentially fatal condition caused by the ingestion of lead. Symptoms of lead poisoning can vary depending on the amount of lead ingested and the individual's age and health. In young children, symptoms may include behavior problems, learning difficulties, anemia, abdominal pain, vomiting and constipation. In adults, symptoms may include high blood pressure, headaches, muscle and joint pain, fertility problems and memory loss. If left untreated, lead poisoning can cause coma or death.