Durham, N.C. — State regulators have cited Durham for having excessive levels of lead in its drinking water.

The citation, issued Tuesday by the state Division of Environmental Health, requires Durham leaders to increase testing for lead and copper and mandates that the city make sure the public knows that high levels of lead were found in tap water.

Durham failed to meet federal safety standards last year for its water. The city tested water at scores of older homes last summer after a child at a city housing project showed signs of lead poisoning.

Lead is especially toxic to young children and can cause brain damage and other developmental problems.

Regulators also cited Durham in January for failing to report the results of some of the water tests conducted last summer. As of result, the city must undergo a more intensive testing program for at least the next year.

Durham officials have maintained that city water poses no health threats.