Marijuana is way more potent than it was back in the 1970s - a result of more sophisticated grow houses, better understanding of plant nutrients and lighting, and advances in breeding techniques. The result is that today's legal recreational markets feature some of the most powerful cannabis in the world - a growing concern to some government regulators that are moving to limit the amount of THC in cannabis products.

While most consumers think of strong bud as a good thing, the leaps and bounds by which cultivation has grown is prompting some concern over whether marijuana has become too potent. According to The Cannabist, two separate proposals have now been filed seeking to limit the amount of THC in Colorado recreational products to around16 percent, a limit many growers and others in the industry have criticized as a arbitrary.

"The 15-16 percent THC figure being thrown around, "actually falls short of the average THC content of modern cannabis flowers, let alone highly purified concentrates," as Ry Pritchard wrote in a recent op-ed.

Concern about high THC content in edibles

Edibles, too, are the subject of the how-much-is-too-much debate. In addition to the Colorado proposals to limit the THC content in cannabis products, Oregon's Health Administration is moving forward with a plan of capping the THC content of recreational edibles at 5 milligrams. In other legal states like Colorado and Washington, edibles are currently capped at 10 milligrams per dose.

"We felt that a cautious approach was probably the best approach," Andre Ourso, manager for Oregon's medical marijuana program, told Cannabis Business Executive.

Ourso said consumers who don't experience the effects they're looking for after a 5 milligram serving can always ingest more. "I think this is the best compromise we could come to," he said.

While the idea of reaching a compromise makes sense, less clear is how that kind of legislation would impact the sale of concentrates, like budder or shatter, which can average as much as 62.1 percent THC according to a state study out of Colorado.

THC restrictions could revive black market

If making products above 15 percent THC is criminalized, illegal concentrate production - already a major concern in many jurisdictions - could also become more common.

In the same way, consumers unable to access sufficiently potent products at state-run dispensaries could also be inclined to return to the black market. As marijuana industry compliance professional Mark Slaugh tells The Cannabist, the "unconstitutional" THC limit seems to have been developed without adequate research

"I don't think a lot of thought was put into the proposals," said Slaugh, also the executive director of the Cannabis Business Alliance. "This bill threatens to wipe out most infused product manufacturers, and its language is unclear as to what to do with edibles."

As Pritchard puts it, "the whole thing just makes no sense and is completely lacking in scientific rigor or justification."

h/t Leafly, The Cannabist, Cannabis Business Executive.