A school district in Newark, N.J. is shutting off its water fountains after testing found lead in building drinking water, according to state health officials.

Drinking water at 30 schools in Newark tested positive for levels of lead higher than the federal standard, according to a joint announcement from the New Jersey Department of Environmental Protection and the Newark Public Schools. The Environmental Protection Agency’s action level for lead, the threshold requiring additional action, is 15 parts per billion and drinking water in Newark’s schools ranged from 16-558 ppb.

Of the some 300 water samples taken from the Newark school buildings, 59 were above the EPA’s action levels for testing and no building had more than four samples above the action level. The water in Newark’s schools is nowhere near some of the high levels of lead in Flint, Michigan—one home there tested as high as 13,200 ppb.

Schools remains in session and New Jersey officials are urging parents not to worry, adding in the release: “Parents should have no concerns about students’ water and food consumption at the school while the situation is addressed.”

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