Minnesota Bill Would Cap Marijuana THC at 15% for Flower, 30% for Concentrates, Mandate New Warning Labels

A Minnesota lawmaker has filed legislation that would place strict THC caps on adult-use marijuana products while imposing sweeping new warning and labeling requirements. Senate File 3591, introduced today by State Senator Matt Klein (D), would limit marijuana flower sold in the adult-use market to no more than 15% total THC and cap concentrates at 30% total THC. The measure would also restrict topical and transdermal cannabis and hemp products to 500 milligrams of total THC per package.

Under the proposal, products such as flower or prerolls infused with additional THC or other psychoactive cannabinoids would not be allowed for sale in the adult-use market. The bill also reinforces prohibitions on products designed to resemble candy, pastries, animals, fictional characters or other items commonly associated with children.

Beyond potency limits, SF 3591 would require marijuana retailers to post multiple new warning notices at each location. These include statements linking cannabis smoke to heart and lung disease, warnings about psychotic symptoms and mental health risks for those under 25, and cautions about delayed effects from edibles.

The legislation would further mandate expanded warning statements on product packaging, including language about brain development, dependence, psychosis risk, pregnancy concerns and driving under the influence.

If enacted, the measure would significantly reshape Minnesota’s adult-use marijuana market by lowering allowable THC levels and increasing regulatory requirements for labeling and retail operations. The bill has been referred to the Senate Commerce and Consumer Protection Committee for consideration.