Groups opposed to marijuana legalization spoke out in Hartford Wednesday, urging lawmakers to keep recreational pot illegal.

Anti-pot groups are warning legislators about the effect legalizing recreational marijuana would have on teenagers, even though the proposed law would only make weed legal for folks 21 and over.

The different groups opposed to legalizing recreational marijuana all had a similar message for Connecticut lawmakers: Legal pot will be bad for kids.

“I see it every day in the people I go to school with,” said Guilford High School Senior Elizabeth Abernathy. “By legalizing it for people over the age of 21, you are just opening the gates for people of all ages to gain access as it will be easier to obtain.”

“We know by looking at other states where marijuana is legal that new products will evolve with edibles and vapes and that these products will appeal to younger users,” said Scott Cochran of Madison Youth Services.

You don’t have to go far to find those products. As a New Haven billboard for a weed-finding app shows us, it is legal just over the Massachusetts border.

Related: Lamont ready to support recreational marijuana legislation

“The states that have legalized marijuana all have the highest rates of adolescent cannabis use,” said Dr. Deepak Cyril D’Souza, a psychiatrist with the Yale School of Medicine. “It’s just a matter of time that if we were to legalize, we would see the same trend.”

That is up for debate, however. A federal study a year ago showed that in Colorado, teen pot use actually went down 2 percent after legalization. A state study found that in Colorado, “…youth marijuana use has not changed since before legalization.”

Pro-legalization activists point out proposals in Connecticut would severely restrict access.

“I want to say this bill is an adult-use legalization bill,” said Joe LaChance, deputy director of the Connecticut chapter of National Organization for the Reform of Marijuana Laws. “So we’re talking about what are probably going to be the most restricted and regulated system in the country, knowing things in Connecticut.”

An expert from Yale says if teens are exposed to cannabis, they are more likely to develop mental illness, more likely to try other drugs and can have trouble in school.

“Acute exposure to cannabis can affect many of the cognitive processes that are critical to the life of a student, such as attention, memory processing speed, so on and so forth,” said Dr. D’Souza.

Governor Ned Lamont and several top Democrats have indicated they want to follow the lead of Massachusetts and Colorado and make it legal for anyone 21 and older to consume pot. There is also some debate whether the costs of legalization in terms of health care and traffic accidents might be greater than the millions of dollars the state hopes to make by taxing legal weed.