Days after an investigation by the Colorado Department of Public Health and Environment determined that marijuana intoxication was the chief contributing factor in the death of a 19-year-old teenager in the state last year, the United States Centers for Disease Control and Prevention (CDC) issued a statement calling for clear labels and limited portion sizes of marijuana edibles.

The teen, identified as Levy Thamba Pongi -- an exchange student from the Democratic Republic of Congo -- died in March last year when he jumped off a balcony on the fourth floor of his building after consuming a marijuana cookie containing 65 milligrams (mg) of Tetrahydrocannabinol -- the active ingredient in marijuana -- which was over six times the recommended serving size of 10 mg of THC.

“This case illustrates a potential danger associated with recreational edible marijuana use,” the CDC said, in the statement. “Although the decedent in this case was advised against eating multiple servings at one time, he reportedly consumed all five of the remaining servings of the THC-infused cookie within 30–60 minutes after the first serving, suggesting a need for improved public health messaging to reduce the risk for overconsumption of THC.”

According to the CDC, edible marijuana products, such as cookies,  brownies and candies, account for approximately 45 percent of Colorado’s marijuana sales. Because absorption of THC is slower when ingested -- compared to when it’s smoked -- people tend to consume multiple servings before they start experiencing the “high” from the initial serving.

“Consuming a large dose of THC can result in a higher THC concentration, greater intoxication, and an increased risk for adverse psychological effects,” the CDC said, in the statement.

After alcohol, marijuana is the most commonly used recreational drug in the U.S., with nearly 20 million past-month users. As of now, four states -- Alaska, Colorado, Oregon and Washington -- have legalized recreational use of marijuana for people older than 21 years.

The CDC recommended that all states where recreational marijuana is currently legal should have clear guidelines and labels for marijuana edibles. Under new rules enacted in Colorado in February, for instance, edible marijuana products should contain no more than 10 mg of THC -- or clearly demarcate each 10 mg serving -- and must be child-proof.

“Other states permitting recreational marijuana use could potentially reduce adverse health effects by considering similar THC limits in marijuana edible products, and by enforcing clear labeling standards that require information on multidose products,” the CDC said, in the statement.