ST. CLOUD (AP) — The Epilepsy Foundation of Minnesota has canceled plans to launch 60,000 balloons amid criticism of the event’s potential effects on the environment and wildlife.

Before announcing the balloon launch to celebrate its 60th anniversary, the foundation said it checked with the Minnesota Pollution Control Agency and Department of Natural Resources and was not informed of any legal and environmental concerns.

The MPCA and DNR later said that while state laws don’t specifically address balloon releases, they would be considered littering, which is illegal.

The “Rise Above Seizures” event scheduled for May 15 drew opposition from some volunteers and environmental groups who said pieces of the balloons would fall to the ground after they break, creating litter and posing a threat to birds and wildlife. On its website Friday, the foundation instead encouraged supporters to be creative with their balloons and send in photos and video of how they are honoring their loved ones with epilepsy.

“The foundation envisions balloon sculptures, school children making art projects and more,” it stated.

“We regret that an event designed to bring awareness to our important cause has been caught in the crossfire of an environmental debate that we are not qualified to enter,” said Vicki Kopplin, the foundation’s executive director.