<Li> July 30 - The DEQ announced that in June and July 2018, of the 420 filtered water samples from Flint Public Schools tested, 100 percent were below 15 parts per billion of lead, and more than 99 percent met the 5 ppb bottled water standard . </Li> <P> Some water service lines in Flint were installed between 1901 and 1920 . As with many other municipalities at the time, all of the service lines from the cast iron water mains to end users' homes were constructed of lead, because it was relatively inexpensive and easy to work . Lead pipes can leach lead into the water, especially if certain contaminants are present . However, the water from the Detroit Water and Sewerage Department, where Flint had obtained its water since 1967, had been treated well enough that the leaching from the lead pipes was at levels considered acceptable by state and federal environmental protection agencies . There are an estimated 43,000 service lines in the city; these include 3,500 lead lines, 9,000 known galvanized lines, and 9,000 unknown service lines . </P> <P> Lead exposure across the U.S. has fallen dramatically since the 1980s, but no blood - lead level is considered completely safe . Children under age five, and especially infants and unborn children, bear the greatest risk of deleterious and irreversible health outcomes . From 2012 to 2016, the CDC set a "reference level" of 5 micrograms per deciliter (μg / dL), in order to target for case management the 2.5% of young American children with the highest blood - lead levels . At 45 μg / dL, chelation therapy is considered . Among the many ways lead can enter a modern American's bloodstream is through lead plumbing . Acidic water makes it easier for the lead found in pipes, leaded solder, and brass faucets to dissolve and to enter a home's drinking water . Therefore, public water treatment systems are legally required to use control measures to make water less acidic . Plumbing that contains lead is often found in buildings constructed in the 1980s and earlier . </P> <P> From 2011 to 2015, Governor Snyder appointed four emergency managers to control Flint's finances . After 2015, the city continued to receive financial guidance under the lesser oversight of a Receivership Transition Advisory Board . </P>

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