The legalization of recreational marijuana has become widespread in the U.S. since Colorado’s adoption in 2012. Today, 24 states and the District of Columbia have legalized cannabis products.

But none of these jurisdictions require adequate product warnings, calling into question state commitment to informing the public about the health risks of a now widely available drug, as is already done for alcohol and tobacco.

That’s because every state makes its own choice about whether — and what — to include on its cannabis products. One recent study found that there are currently 12 different health warning label regulations incorporated into marijuana products in at least one state. According to new research I conducted for the American Enterprise Institute. Nevada and California require the highest number at eight and seven, respectively — but even they fail to meet the mark.

The 12 dangers or warning label standards include:

1. Keep away from children
2. Don’t use while breastfeeding or pregnant
3. Don’t drive under the influence
4. Potentially delayed effects
5. Physical health risks of smoking
6. General physical health risks
7. Mental health risks
8. Risk of psychosis for high-potency products
9. Minimum font size of text
10. Warning must contrast with background
11. Rotating warning
12. Warning must appear on front of package

States, not the federal government, decide what to include on cannabis product warning labels because marijuana is a Schedule I dangerous drug under the Controlled Substances Act. By contrast, tobacco products must be uniformly labeled as carcinogens per federal law.

Whether recreational marijuana tax revenues are devoted to public health education on cannabis effects is based on state law and thus also varies greatly. Only five states require “dedicated” taxes to support public health education regarding cannabis safety risks, such as impaired driving. More states provide this service to diminish tobacco use, even though the latter is declining and cannabis use is increasing.

A review of warning labels on cannabis packaging reveals that there is wide variation across states, with many including minimal information about health risks. Although many states in which adult-use marijuana is legal require specific text and warnings to appear on cannabis packages, not all do. Only 11 states have laws that require packages to state “Keep drugs away from children” or that otherwise clarify that the product is not to be consumed by children.

Similarly, many states require packages to be child-resistant without including warning labels against keeping such packages within the reach of children. And warning labels restricting consumption by pregnant women are required in only nine states.

Just 10 of the 25 jurisdictions require labels warning that cannabis use can impair the consumer’s ability to drive or explicitly note the danger of driving while under the influence. Although six states mandate warnings about general physical health risks associated with consuming marijuana, only one requires packages to warn about the health risks for lungs associated with smoking marijuana. Illinois is the only state to require packaging to inform consumers about the risk of psychosis, but several states demand that sellers notify users about the potential for marijuana to be addictive or “habit forming.” 

Cannabis package labels typically specify tetrahydrocannabinol (THC) or cannabidiol (CBD) percentages, which could be interpreted as advertising as much as warning. Four states require warnings that the effects of cannabis can be delayed by about two hours — important information for those who would operate a motor vehicle — and that possession of the drug may be illegal outside the state.

Utilizing this new research, which examined laws for the 25 jurisdictions which have legalized cannabis products, we have has assigned a public health grade for each. It concludes that only five jurisdictions deserve an A while 12 are assigned an F.

A: California, Illinois, Nevada, Colorado, Oregon
B: Alaska, Arizona, Oregon
C: Guam, Minnesota, New York
D: Delaware, Massachusetts
E: Maryland, Michigan
F: Connecticut, District of Columbia, Maine, Missouri, Montana, New Jersey, New Mexico, Ohio, Rhode Island, Vermont

President Trump has indicated he’s considering reclassifying marijuana as a less dangerous Schedule C drug. In many ways that would be unfortunate, as we see growing problems with cannabis-impaired driving and overuse by young adults, whose developing brains can be particularly at risk.

A federal relaxation would at least open the door to warnings akin to those on cigarette packages — uniform warnings across the country about a product we may have legalized without enough effort to discourage its use.

Howard Husock is a senior fellow at the American Enterprise Institute where he focuses on municipal government, urban housing policy, and civil society.