FLINT, Mich. (WWJ/AP) – Doctors are urging Flint to stop using water from the Flint River after blood tests revealed more children in the city with higher levels of lead.

Researchers led by a doctor from Hurley Medical Center looked at blood samples taken this year from more than 1,700 children living in Flint. They found that the percentage of kids with above-average lead levels has nearly doubled. In certain areas, it has tripled.

READ MORE: Republicans Kept Off Michigan Ballot Turn To The Courts

The results were announced Thursday, although city officials were briefed Monday.

“This is not what our community needs,” said Dr. Mona Hanna-Attisha.

Flint began using Flint River water last year after leaving the Detroit system, which draws water from Lake Huron. The river water is releasing lead found in old pipes and service lines.

Hanna-Attisha said a change is needed and soon.

READ MORE: Here Are Some Memorial Day Events Happening In Metro Detroit

“We are advocating for a switch back to a Lake Huron water source,” Hanna-Attisha said. “So, be it either from Detroit or from this new pipeline that’s going to be built. But this pipeline’s not going to be built until, I think, the summer of 2016…and our kids cannot have continuous exposure until then.”

Hanna-Attisha says there is “no safe level of lead for a child.”

Even at very low levels, she said, research shows decreasing IQ levels, behavior disorders and other serious medical issues.

WWJ Newsradio 950 has a call out to the city of Flint seeking comment.

MORE NEWS: City Of Dearborn Hosts Emergency Baby Formula Distribution Event

TM and © Copyright 2015 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2015 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.