The drinking water in one central Wisconsin city could be at risk.
Mosinee's Annual Drinking Water Quality Report showed higher amounts of lead in the city's water.
Marathon County Health Department leaders say the particles come from old lead water pipes.
"If the water is corrosive and sits in the pipe, it will dissolve lead from the pipes and then there will be lead present in the drinking water," said Public Health Lab Director Ruth Marx.
In eight of the 41 test samples taken in the city, the lead level was above the safety limit.
"That's why I had it tested to make sure our water was fine," said Mim Bemis of Mosinee.
The report says the water is safe to drink, but officials are closely monitoring those lead levels.
Officials say if the water hasn't been used for six hours or more, homeowners should run water for several minutes before drinking or cooking.
Residents say they are closely following that advice.
"In case there is a deposit in the pipes, that we flush it before we use it," said Harold Schilling of Mosinee.
Health leaders say people should also avoid using hot water from the tap for cooking. Instead, they should use cold water and heat it up.
Marx says the Mosinee Water Utility is working to make the water safer.
"They've added chemicals to the water that will bring the pH up to make it less corrosive," said Marx.
Homeowners say that puts their minds at ease.
"I know they're watching it very carefully and they test the water all the time," said Nancy Schilling of Mosinee.
Officials recommend people living in older homes to get their water checked, if they're worried.