Lead is a heavy metal that has been an additive for a variety of household products, including interior and exterior household paint.  While lead made paint more durable, it also proved to be toxic to humans and animals.  The use of lead paint in housing was banned in 1978.    When intact and undamaged, lead may not cause problems.  When lead deteriorates and is ingested or breathed into the body, it becomes a health hazard.  The info graphic below demonstrates the issues that lead can cause in children.  While children and pregnant women are at great risk, all humans should avoid exposure to lead.