Lead contamination is not just a problem for Flint. Over 19 Detroit schools have found elevated lead or copper levels in their water, ABC News reports.

School officials began collection water samples two weeks ago as a proactive and precautionary measure. The school district has not released the specific level of contamination about the levels found in nearly a third of the 62 schools tested.

Officials did say, however, that they are working fast to fix the problem. According to ABC News, district spokeswoman Michelle Zdrodowski said, “While additional testing is completed, DPS [Detroit Public Schools] immediately shut off all drinking fountains in the affected schools until further notice and is providing additional bottled water for students and staff.”

The schools are also providing meals that do not require adding any extra water.

Few schools and childcare centers are required to check for lead because they receive their water from municipal systems that test at other locations. This includes the Detroit school system.

This inconsistency in testing makes children the most vulnerable because a build up in lead particles happens when the water goes unused for long periods of time. Most school buildings in the U.S were built in the 1970s, but it wasn’t until 1986 that lead pipes were banned.

When consumed, lead is a very dangerous neurotoxin that can damage a child’s brain development. Lead exposure contributes to approximately 600,000 new cases of  intellectual disabilities in children each year.

Lead in the water has been a long standing issue in Michigan, as residents in nearby Flint were exposed to dangerous levels of lead when the city reconnected it’s water system to the contaminated Flint River.

It is not yet known how much it will cost to fix this issue. State lawmakers recently approved $48.7 million in emergency funding to keep schools open through the end of the financial year.