Is your drinking water supply contaminated with toxic chemicals? Check this database

Because of the elevated levels of PFAS found in its public water sources, Wayland is distributing bottled water to the public.Pat Greenhouse/Globe Staff

Since Massachusetts enacted new safety regulations last fall, more communities have found elevated levels of toxic chemicals known as PFAS in their drinking water.

Results are now available from half of those public water sources required to start testing — those that supply more than 10,000 people. Of them, 20 percent have reported concentrations above what state regulations allow.

Many of these communities are still delivering the contaminated water, despite a growing body of research that links PFAS exposure to health risks such as cancer, compromised immune systems, and a range of diseases. Polyfluoroalkyl substances are also known as “forever chemicals” because they never break down in the environment.

Search for your town below to see if its water supplies exceeded state standards.

If you can’t find your town, it may be included as part of the Massachusetts Water Resources Authority (MWRA), which provides water for Boston and 60 other communities. These data also do not include hundreds of additional smaller public water suppliers that will be required to start testing later this year and next year.