DENVER (CBS4) – The results of a new study about the impact of Colorado’s marijuana legalization is raising troubling questions for parents. The study cites a significant increase in marijuana-related traffic deaths, hospital visits and school suspensions.

The parents CBS4’s Melissa Garcia spoke with say they’re concerned about their children seeing messages promoting pot all over town. Activists say it’s the way pot is marketed and sold that has started to create some serious problems.

“I never dreamed in a million years that this would happen to my son,” said parent Kendal, who didn’t want to use his last name.

Kendal came home one evening to find his 13-year-old son unconscious from what he says was a marijuana overdose.

He was gray. His heart wasn’t beating and he wasn’t breathing,” he said.

Kendal used CPR to resuscitate him and later talked to his son’s high school peer and supplier.

“I had heard from kids that there was 60 percent of this particular high school using drugs, and she shook her head and said, ‘That’s way low,'” Kendal said.

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“Kendal’s story breaks my heart, but I’ve got to tell you we have heard that from hundreds and hundreds and hundreds of parents throughout the state,” said Diane Carlson, Smart Colorado co-founder.

Carlson says Colorado’s child and teen use of marijuana has become an epidemic.

“Kids have no idea how dangerous or harmful Colorado’s pot is,” she said.

According to a report released this month by the Rocky Mountain High Intensity Drug Trafficking Area, Colorado saw a 29 percent increase in emergency room visits, and a 38 percent increase in hospitalizations during retail marijuana’s first year.

The study states that over 11 percent of Colorado’s 12 to 17 year-olds use pot — 56 percent higher than the national average. It also cites a 40 percent increase in drug-related suspensions and expulsions — the vast majority from marijuana.

Carlson says the culprit is its commercialization.

“Marijuana might have been legalized in our state; it did not have to mean massive commercialization and promotion of marijuana use,” she said.

LINKS: Read The Full Report | Smart Colorado