SOUTH PORTLAND – Smoking marijuana both for medical and recreational use has gained broad-based support in recent years, with 21 states, including Maine, now allowing people to use and possess marijuana to treat medical conditions and two states also legalizing recreational use.

In light of that changing landscape, the Opportunity Alliance and South Portland High School will host a community program next week designed to help parents, teachers, coaches and others who work with teenagers get the message out that there are very real dangers associated with using marijuana regularly.

The event, “Parenting in the Age of Legalization: A Conversation on Preventing Teen Substance Use,” will be held at South Portland High School on Wednesday, April 30, at 7 p.m. This program is free and open to the public, according to coordinator Liz Blackwell-Moore.

According to a press release issued by the Opportunity Alliance, the program will be a “straightforward dialogue about the impact of marijuana use on brain development, mental health and college readiness. (Attendees) will learn valuable information about the impact of marijuana use on youth and, most importantly, how to address the issue with teens.”

Blackwell-Moore, who is a public health program specialist with the Opportunity Alliance and one of the panelists speaking next week, said it’s important to have a community discussion because “marijuana use is harmful for young people.”

She added, “substances affect teenagers very differently than adults, and marijuana is no exception.” According to her research on the issue, one out of six teens that use marijuana weekly will become addicted.

Blackwell-Moore said studies also show that teens who use marijuana weekly double their risk of depression or anxiety and are three times more likely to have suicidal thoughts. In addition, heavy marijuana use can lead to attention, learning and memory problems, and, she said, marijuana is the substance most related to school dropout.

“To keep teens from using, the community must work together to send the message to young people that it is dangerous to them, no matter what people think about legalization for adults,” Blackwell-Moore said.

According to the 2011 Maine Integrated Youth Health Survey, Maine high school students who did not think there was a risk in smoking marijuana regularly were six times more likely to smoke marijuana than their peers who thought it was harmful, she added.

And, during the past four years, there has been a 20 percent decline in the number of high school students who think using marijuana once or twice a week is harmful.

That’s why “having accurate information about the impact of marijuana on teens and having tools to prevent them from using it, will be increasingly important,” Blackwell-Moore said.

In all, “teen alcohol and drug use is a community problem that requires a community response,” she said. “What we hope is that this event will help continue the conversation in the community about the most effective ways of preventing our young people from using drugs and alcohol.”

Blackwell-Moore said, “Our hope is that attendees will walk away from the event with accurate information on how marijuana impacts the brain development, the mental health and the long-term success of young people and that they will have a few concrete tools to prevent their teen from using.”

She said anyone who lives or works with a teen would benefit from attending next week’s discussion. “We know that parents have a very large impact on their own child’s decision about using drugs and alcohol (and) this event will provide parents with some clarity about why marijuana is harmful to teens,” Blackwell-Moore added.

She said there are two parts to next week’s discussion regarding marijuana use among teens.

The first is to give parents, and other adults, an opportunity to hear from local experts about the impact of marijuana use. The second is to give attendees the opportunity to talk about the best ways to prevent teens from using the drug.

In addition to Blackwell-Moore, the other speakers next week will be Pender Makin, director of the REAL School; Greg Marley from the Maine chapter of the National Alliance on Mental Illness; and LeeAnne Dodge, director of student life at the University of Southern Maine.

Blackwell-Moore said the Opportunity Alliance partners with the South Portland School Department on a regular basis. Public health staff at the Opportunity Alliance have also worked with the schools on various tobacco prevention initiatives, according to Blackwell-Moore, and on substance abuse prevention. Staff from the Opportunity Alliance have also trained faculty and staff at the high school on best practices for preventing substance abuse, worked with the social work staff to create and give trainings to athletic teams on alcohol and drug prevention and created many prevention materials that the school disseminates to parents on a regular basis.

“Teen alcohol and drug use is a community problem and the South Portland school district has been an active partner, willing to do its part and more to address the problem in collaboration with parents, police and other community organizations,” Blackwell-Moore said.