Lead is a metal that occurs naturally in the earth's crust. People have spread it through the environment in many ways. Lead used to be in paint and gasoline. Lead can still be found in contaminated soil, household dust, drinking water, lead-glazed pottery and some metal jewelry.

Breathing air, drinking water, eating food or swallowing or touching dirt that contains lead can cause many health problems. In adults, lead can increase blood pressure and cause infertility, nerve disorders and muscle and joint pain. It can also make you irritable and affect your ability to concentrate and remember.

Lead is especially dangerous for children. A child who swallows large amounts of lead may develop anemia, severe stomachache, muscle weakness and brain damage. Even low levels of lead are linked to lower IQ scores.