There is a glassed-in room called a negative pressure chamber squeezed inside another room on an upper floor of a research building on the Johns Hopkins Bayview Medical Center campus.

“We call it the smoke box,” said Ryan Vandrey, a professor in the Hopkins’ Behavioral Pharmacology Research Unit who helps run the Cannabis Science Lab in Baltimore.

It’s about as fancy as its nickname, but it’s in one of the most advanced marijuana research labs in the country, where participants go to, well, smoke marijuana in the name of science. It’s one of a small number of labs in the country slowly churning out vital information about a drug that is already in wide use.

Marijuana is now a billion-dollar industry in Maryland, with more than 118,700 registered patients and more than a 1.2 million medical and recreational dispensary transactions monthly, according to the Maryland Cannabis Administration. Sales provide income to small businesses, public health programs and the state’s general fund.

As of July 1, it’s been a year since Maryland legalized recreational cannabis for adults and seven since medical dispensaries started sales. Gov. Wes Moore recently pardoned more than 175,000 people with minor possession and paraphernalia charges. And now at the federal level, authorities plan to reclassify cannabis as a less dangerous drug, more akin to ketamine and steroids than heroin and LSD. That could potentially remove research red tape and spur more studies of benefits and risks, as well as more scientists to do the studies.

“Millions of people are using cannabis, and there are 18 people [labs] studying it,” Vandrey said. “We need to know more about it.”

Like, how much is enough? How do you know how potent it is? What exactly is it good for, and who should steer clear? Does it interact with prescriptions, and which ones?

Vandrey and his colleagues plan to continue chipping away at the list, with the latest study aiming to determine if, and how much, potency changes if you smoke, eat or drink the active ingredients in cannabis.

The process to reclassify cannabis by the U.S. Drug Enforcement Administration is just beginning, and it will be slow. So for now, Vandrey and his colleagues have to stick with a long and arduous approval process that can add months to preparation for studies even for seasoned scientists.

Vandrey said Hopkins wants to be among those the federal government taps to show others how to stand up a proper cannabis research operation, and possibly work together on standardization for the industry with universal product labels and symbols that would make it easier for the public to know what they are consuming.

Others already are teaching the cannabis workforce about the evidence on what maladies it’s good for, including nerve pain and extreme weight loss from anorexia and cancer treatments.

The University of Maryland School of Pharmacy led the nation in establishing a graduate program where students can study medical cannabis science, therapeutics and policy. Scientists there do research, but they’re not directly involving the plant yet.

Cannabis remains illegal on the federal level even with the reclassification, and cumbersome regulations remain, noted Chad Johnson, an assistant professor in the Department of Pharmaceutical Sciences and co-director of the university’s Graduate Studies in Medical Cannabis program.

“The door will not just fling wide open,” said Johnson, who also serves on the state’s Advisory Board on Medical and Adult-Use Cannabis and who spoke during a recent panel discussion with colleagues from the University of Maryland, Baltimore.

The law is also blurred by other federal policies, including a 2018 bill legalizing hemp, which comes from the cannabis plant. Without layers of regulations, it’s created loopholes to sell related products outside of the state’s cannabis dispensary system in Maryland and elsewhere, said Mathew Swinburne, managing director of a newly launched cannabis legal resource center at the university’s Francis King Carey School of Law.

Swinburne said that still needs to be sorted out. But within the official system in Maryland, he said there are laws against advertising to children to rules that assure adults of quality.

Swinburne’s state-funded center and local health departments have identified youth access to marijuana as a top concern.

It’s not clear, however, if more young people use cannabis where it’s legal for adults, said Leah Sera, an associate professor in the university’s Department of Practice, Sciences and Health Outcomes Research and co-director of the graduate cannabis program.

“From other states and studies published after legalization, adult use of nonmedical cannabis increases after legalization, but it’s not true for adolescents,” said Sera, who is collecting information for the state advisory board.

“It doesn’t mean there aren’t concerns,” she said. “It doesn’t mean we won’t have strong public health instruction in schools and for parents.”

The latest data from the Maryland Youth Risk Behavior Survey just released by the Maryland Department of Health found 14.4% of high school students were using marijuana in 2022, before adult recreational use was approved. That’s down from 19.8% in 2013.

Sera noted another fear has proven unfounded since approval of adult recreational use: People relying on medical cannabis have not struggled to acquire their doses.

She and the other scientists said they look forward to more research to answer questions they have now, and new ones that will arise in the evolving industry. She said already there’s reduced stigma around medical marijuana thanks to changes in law and advances in research.

“In the next five years,” she said, “we’ll probably see a lot more changes.”