When you pour a glass of water, most assume it's safe to drink and don't usually think about what's actually in the water.
The nation's drinking water supply was on the center stage after the water crisis in Flint, Michigan.
Since 2010, water utilities' testing has found pollutants in tap water across the country, according to an analysis done by Environmental Working Group of 30 million state water records.
Contaminants detected in water samples are perfectly legal but could pose health risks, according to Environmental Working Group's experts.
The organization developed a map and a free online database to test water quality in every ZIP code.
Environmental Working Group pulled data from 50,000 public water systems in all 50 states.
- 40,000 water systems included cancer-causing material
- 78 associated with brain and nervous system damage
- 19,000 public water systems contained at least one detection of lead that could pose a risk to small children.
If you want to find out more about Environmental Working Group water research and how your ZIP code shapes up, visit the EWG website.