Heavy metal poisoning occurs when toxic metals such as lead, mercury, arsenic, or cadmium accumulate in the body at harmful levels, disrupting normal cellular and organ function. Exposure may result from contaminated water, food, industrial emissions, occupational contact, old paint, certain traditional remedies, or environmental pollution. Symptoms vary depending on the specific metal and level of exposure but may include abdominal pain, nausea, neurological changes, memory problems, fatigue, kidney impairment, or developmental delays in children. Because heavy metals can build up over time, chronic exposure may lead to long-term organ damage. Diagnosis typically involves blood or urine testing to measure metal concentrations and assess the extent of toxicity.