The latest discovery of lead in the water at Long Island schools is raising concerns about how widespread the problem may be.

High levels of lead have been found in 12 water fountains within the Northport-East Northport Union Free School District.

According to test results posted on the district's website, two water fountains at the Dickinson Avenue Elementary School have been shut down for having high levels of lead.

In Valley Stream schools, four fountains were found to have higher-than-acceptable levels of lead.

The Farmingdale School District tells News 12 Long Island that it will also begin testing its water fountains, taps and faucets to make sure they are safe.

Many districts across the Island are testing or in the process of finding a company to come in and sample water. While water suppliers are required to make sure the water is safe going into the building, there is no law mandating the schools test the water.

News 12 Long Island reached out to the Nassau-Suffolk School Boards Association for a comment. It said this testing needs to be done to reassure kids and parents that their school's water supply is safe.