FLINT, MI -- New independent testing of Flint water for lead matches results of both independent and city testing last year.
A report posted online by the state Department of Environmental Quality this week says the 90th percentile for 51 high-risk homes tested in Flint from May through December was 4 parts per billion of lead -- less than half the current federal and future state action level.
Professors from Michigan State University and the University of Notre Dame supervised the testing, which is the result of a settlement agreement reached after a lawsuit filed by the Concerned Pastors for Social Action and others against the city of Flint and the state.
Dated Jan. 21, the report by professors Susan J. Masten and Kyle Doudrick says the number of homes tested with lead service lines dropped from the first independent round of testing from 92 to 51.
“The number of residents ... to participate decreased over the summer" and fewer homes with lead service lines were available to test as the city continued its program to remove and replace lead and galvanized steel connections, the report says.
The Concerned Pastors and Natural Resources Defense Council were among the plaintiffs in the lawsuit that led to the third-party testing.
Flint’s 90th percentile for lead has been 4 ppb in the last four rounds of testing -- two by the city and two by the independent testers.
The U.S. Environmental Protection Agency action level for lead is 15 ppb, and the state limit starting in 2025 will be 12 ppb. The 90th percentile is a formula used by EPA to measure the prevalence of lead in public water systems nationwide.