If you are interested in learning about lead in the water you drink you can gather a sample and send it to a local lab for testing, though this method can be costly. An at home lead water test kit can often provide results with up to 99% accuracy in around 10 minutes.
The EPA has determined there is no safe levels of lead in water, however they do indicate that a concentration above 15 ppm requires action to prevent health risks to children and pregnant women in particular. Think of parts per million (ppm) as a single penny in $10,000. It is a very small amount but its affects can be devastating.
If you find elevated levels of lead in your home water supply you should stop drinking or using the water to cook. Note: Boiling water is not effective at destroying lead. You can still safely wash your hands, shower, and bath as lead dissolved in water does not absorb through skin.