Should there be limits on THC? As a wave of adult-use cannabis legislation sweeps across the country, many states are proposing strict potency limits, hoping to keep consumers safe. 

While most regulated markets set limits on the amount of THC per package and daily purchasing limits, a new round of legislative proposals is seeking to go one step further. In Florida, New York, Washington, and Montana, lawmakers have tried to limit THC in flowers and concentrates. In Vermont, this approach is already law.

Among cannabis experts, there is a growing consensus about the risks posed by super-strong cannabis. Yet, for some patients who have a chronic condition, high THC levels are both practical and effective. 

Let\’s look at the risks associated with potent cannabis products and the feasibility of implementing these legislative restrictions.

Real Risks from High-potency Cannabis

Despite the claims from longtime advocates that cannabis is totally safe and non-addictive, the current scientific understanding suggests otherwise.

Nearly all concerns about cannabis stem from THC. As one of the main cannabinoids, it\’s also the only one with intoxicating effects. In particular, there are genuine concerns about adolescent consumption. 

When teenagers habitually consume high-potency cannabis, the research tells us there are long-term effects on brain development, IQ scores, and mental health. Early-onset cannabis use during these formative years is detrimental, especially frequent consumption of high-potency products.

Beyond adolescent consumption, which is outlawed everywhere cannabis is legal, there are additional issues linked to high levels of THC. For example, in 2014, the Schizophrenia Bulletin published a study looking at first-onset psychosis and cannabis use patterns. The results spoke for themselves: \”Daily use, especially of high-potency cannabis, drives the earlier onset of psychosis in cannabis users.\”

A 2015 study, published online through the Cambridge University Press, determined high potency cannabis led to a greater risk of cannabis dependence. Respondents to the survey reported that high-potency cannabis led to the best experience, but it was also associated with adverse effects like memory issues and paranoia. 

The authors discovered a clear difference between high potency and low potency products. While frequent use of low potency cannabis showed no connection to cannabis dependence, high potency was another story altogether. The authors concluded, \”High-potency cannabis use is associated with an increased severity of dependence, especially in young people.\”

Practical Challenges of Limiting THC

There are very real concerns supporting strict THC limits in legal products, but enforcing these limits could be more challenging than legislators realize.

Take hemp as one notable example. There are already limits on THC for hemp crops, and these have proven incredibly challenging for cultivators to meet. 

Legal hemp must fall under 0.3 percent THC or get the dreaded \’hot\’ label and face immediate destruction. As many farmers have experienced since passage of the 2018 Farm Bill, many uncontrollable environmental factors lead to fluctuations in cannabinoid production. For example, outside stressors impact how much THCa (the precursor to THC) the plants produce. Essentially meaning it\’s often outside the farmers\’ control.

Vermont has placed a limit of 30 percent THC on flower, while other states, like Florida, are seeking limits as low as 10 percent. If \’hot\’ crops are an ongoing issue for hemp growers, it\’s hard to imagine how limitations on THC-rich crops would go any differently than what is playing out in hemp.

But beyond the practical issues of forcing a plant into a restrictive potency box, many legal experts are worried about how potency limits will force sales underground. As a Cannabis Now article explained, the new THC limits are \”darkly reminiscent of the drug war\’s worst impulses.\”

If high-potency cannabis products are illegal, they will very likely make a quick comeback on the black market: unregulated, untested, and much more dangerous to society. 

Challenges for Legislators to Get THC Limits Right

From a public safety perspective, limiting THC in cannabis products could help reduce the prevalence of the associated risks. But, as regulators have already discovered in the attempt to control THC in hemp crops, it\’s more challenging to enforce than one might expect.

A careful and thoughtful approach to setting THC limits is needed. On the one hand, patients need access to high doses under certain circumstances. On the other hand, consumers need some protection from overconsumption of high-potency products. Figuring out how to get this balance right is the challenging part.