By Keith Coffman
DENVER, Aug 11 (Reuters) - Colorado health officials launched a $2 million "Don't Be a Lab Rat" advertising campaign on Monday, aimed at warning young people about the risks marijuana use has on their developing brains.
In 2012, voters in Colorado and Washington state legalized the possession and recreational use of small amounts of pot by adults. Similar ballot measures will go before voters in Oregon, Alaska and the District of Columbia this fall.
The multimedia blitz, targeting youths aged 12 to 15, says the long-term effects of pot use are not fully understood and that young people become unwitting test subjects if they partake, the Colorado Department of Health and Environment said in a statement.
Dr. Larry Wolk, chief medical officer for the department, said the campaign is designed to warn young people that they are engaging in risky behavior if they experiment.
He said more needed to be learned, but that "enough information is available to cause concerns ... (about) the negative effects marijuana can have on the developing brains of teenagers."
The commercials will air on television, online and in movie theaters.
Additionally, life-sized "Lab Rat Cages" will be set up at middle and high schools, at concert venues and other areas frequented by young people across the state.
The campaign is funded by a combination of government agencies and private foundations.
Citing a survey last week that showed fewer Colorado high school students view marijuana as less harmful than those polled before legalization, Governor John Hickenlooper said more young people may be inclined to experiment with pot.
"We have a civic and public health obligation to do everything we can to make our children aware that there are risks for teens when they use marijuana," Hickenlooper said. (Reporting by Keith Coffman; Editing by Daniel Wallis and Jonathan Oatis)