The gummy bears were just sweet. But the "raspberry" and "watermelon slice" candies presented to a group of Colorado legislators on Thursday contained enough THC to make the issue they were contemplating plenty fuzzy.

"If you can't tell the difference, how could a 3-year-old?" Rep. Frank McNulty, R-Highlands Ranch, asked members of the House Health, Insurance and Environment Committee.

McNulty is sponsoring a bill that would require candies and other foods infused with marijuana be shaped, marked or colored in such a way that anyone could identify them as a gateway to several hours of altered consciousness.

Neither the proposed legislation nor a second proposal dealing with concentrates would change the amount of THC — the psychoactive chemical in pot — allowed in edibles.

Committee members passed around and examined a platter containing plastic cups, each filled with a separate candy or cookie.

Marijuana edibles are required to be sold in child-proof containers labeled so users know what they are getting.

But it is a different story once they are out of the package.

"The thing is: A package can go away" — and as goes the package, so goes the warning label, said Rachel O'Bryan, a member of Smart Colorado, a group concerned about the effects of marijuana legalization.

While an individual candy can contain just 10 milligrams of THC, other available marijuana treats can include up to 100 milligrams, the equivalent of 10 servings.

Marijuana isn't deadly, but too much of it, or even a small amount taken by a child or someone unaware of its effects, can result in a trip to the emergency room.

Between 2005 and last year, only six patients who arrived at Children's Hospital's emergency room had to be treated in intensive care because of marijuana, said Dr. Michael Distefano, head of emergency services at Children's Hospital Colorado. So far this year — when recreational marijuana was legalized in the state — that number has almost doubled, he said.

The products can affect everyone differently, sometimes causing symptoms that can range from intense anxiety to excessive sedation or depression. One admitted child, who was experiencing difficulty breathing, had to be put on a ventilator, Distefano said.

Potency amounts vary in edibles, which, more so than in smoking weed, is easier to overconsume.

Marking the food products in some way would also make identification easier for parents, teachers and school administrators. Also, such labeling of edibles would make them more easily identifiable by law enforcement authorities who may stop someone transporting them in states where they aren't legal.

But it won't be easy to mark all edibles in a way that they can be identified as containing marijuana, said Michael Elliott, executive director of Medical Marijuana Industry Group.

"What do you do with soda or a bag of granola?" said Elliott, whose group has reservations about the proposal.

The industry already provides childproof packaging and warns customers to proceed with caution when eating a product that can take more than an hour to kick in, he said.

Some people consume too much in the time that passes before they feel the effects, he said.

Parents have a responsibility to keep marijuana products out of the hands of their kids, just as they do alcohol and prescription drugs, he said.

Elliott's group favors another proposal heard by the committee that would place limits on pot concentrates.

The proposal, co-sponsored by Rep. Jonathan Singer, D-Longmont, would direct the state Department of Revenue to determine how much concentrated pot is equal to an ounce of dried marijuana.

It is possible to carry enough concentrate in a tube made for lip balm to get high hundreds of times, O'Bryan said.

Elliott's group doesn't want anyone to be able to buy an ounce of concentrate, he said.

Tom McGhee: 303-954-1671, tmcghee@denverpost.com