Water filters appear to be successfully removing lead from tap water in Flint, Michigan, an Environmental Protection Agency official told reporters on Thursday.
The EPA released preliminary results after testing the tap water and filtered water in 10 of the homes hardest hit by the water contamination crisis. The agency raised concerns last week that the filters — which are rated to remove lead at levels of 150 parts per billion — might not be up to the job of cleaning Flint's water, where lead levels had reached the thousands of parts per billion.
The EPA tested filters as they were installed in homes as well as filters with new cartridges.
"Luckily, all the results from both filters came back non detect to extremely low," the EPA's Mark Durno said.
The agency will continue to test water in Flint, where dozens of homes' water systems have shown high levels of lead. Durno noted that while Thursday's results were preliminary and only a small sample, they showed good news.
"That is encouraging," he said.
High lead levels remain in unfiltered water, however, and more work will be necessary to determine exactly how lead is getting into water as well as how to stop it, Durno said.
Lead contamination became an issue after the city's water source was switched from Detroit to the Flint River in 2014. The more corrosive river water began leaching lead from old pipes within the city, contaminating drinking water, and leaving residents — particularly children — suffering the effects.
Though the water was switched back to Detroit's system in October, lead from the now corroded pipes has remained at levels hundreds of times above the limits considered acceptable by regulators.
"We can't say the corrosion control is working yet," Durno said on Thursday.
Testimony began Wednesday within the U.S. House of Representatives about how Flint's water became contaminated, and how the problem managed to endure for so long.
In the meantime, authorities are calling on all children age 6 and younger to undergo testing of the lead levels in their blood. Filtered water should be considered safe — if cartridges are changed periodically and faucet aerators are cleaned of any lead particles weekly.
"We believe that that's safe," said Dr. Nicole Lurie, the U.S. Department of Human and Health Services assistant secretary who is coordinating the federal response to the Flint crisis.
Pregnant women and families with young children may want to take additional precautions, she added.
"It may still be prudent to use bottled water, but you can make a choice to go either way," she said.
She reiterated that every home's water should be tested, and all pregnant women and young children should have their blood tested as soon as possible. The government is committed to providing educational and nutritional resources to Flint children to help bridge any developmental gaps, she said.
"It's going to need to start with some testing."