Study Challenges Blood THC Levels as Accurate Measure for Cannabis-Impaired Driving

A new review in Preprints with The Lancet questions whether blood THC levels effectively gauge marijuana-impaired driving. Conducted by researchers from Canada’s Centre for Addiction and Mental Health, Health Canada, and Thomas Jefferson University, the analysis found that most studies report “no significant linear correlations between blood THC and measures of driving.” This calls into question states’ reliance on specific THC thresholds for driving impairment laws.

The review suggests that impairment may relate more to task complexity than THC concentration. Only highly complex driving scenarios, like sudden obstacles or multitasking, showed any link between high blood THC and decreased performance. The authors urge further research that considers driving challenges and cannabis potency to improve safety assessments. This study joins others, including from the U.S. National Highway Traffic Safety Administration, that caution against using blood THC levels as a primary indicator of driving risk.

Poll Signals Trouble for South Dakota Cannabis Legalization Measure

A recent Emerson College poll reveals 50% of South Dakota voters oppose Initiated Measure 29, aimed at legalizing adult-use cannabis, while only 45% support it, with 5% undecided. The survey, conducted from October 19-22 with 825 likely voters, shows significant demographic divides: 68% of voters under 30 favor legalization, contrasted by 64% of voters over 70 opposing it.

The measure would allow possession and home cultivation of cannabis for adults over 21 but does not establish a commercial market. Support mirrors a June Mason-Dixon Polling survey that found 52% opposition. Advocates, like Matthew Schweich of South Dakotans for Better Marijuana Laws, suggest actual support may be underestimated, recalling that a similar measure passed in 2020 but was later overturned. Voter turnout, historically favorable in presidential election years, will be critical for the measure’s fate.

Legal Challenges Emerge Over Hemp-Derived Cannabinoid Regulations

As states impose stricter regulations on hemp-derived products, a series of legal battles unfold. Following the 2018 Farm Bill that legalized hemp, products containing CBD surged, leading to an increase in hemp-derived THC products. Some states, like Minnesota, have developed regulatory frameworks, while others, such as New York, have enacted bans or caps on THC levels.

Recent Developments by State:

• New Jersey: In September 2024, the state amended its hemp law to restrict THC products and defined “intoxicating hemp products.” This prompted a lawsuit (Loki Brands, LLC v. Platkin) claiming federal preemption under the Farm Bill and violations of the Dormant Commerce Clause. A court ruling on October 10 overturned the definition, halting enforcement of certain provisions but keeping age restrictions intact.
• Missouri: After Governor Mike Parson’s Executive Order 24-10 in August 2024 declared hemp-derived THC foods as “adulterated,” the Missouri Hemp Trade Association filed a lawsuit. Following inspections and product embargoes, the state has requested funding for enforcement, indicating a continued effort to regulate hemp-derived THC.
• California: Emergency regulations were enacted in September 2024 to limit THC in hemp products, leading to a lawsuit (U.S. Hemp Roundtable, Inc. v. California Department of Public Health). A court denied a temporary restraining order, affirming the state’s authority to regulate hemp products for public health, despite arguments of Farm Bill preemption. The regulations will remain until March 2025.

State governments are prioritizing the protection of youth by preventing access to hemp-derived THC products for individuals under 21, aligning with existing regulations for alcohol and cannabis. Additionally, courts are largely rejecting arguments that the Farm Bill preempts state regulations, allowing states to impose stricter controls on hemp-derived products. As more states enact similar regulations, additional lawsuits are expected, with recent legal challenges in Louisiana and ongoing restrictions in other states likely to lead to further disputes. Lastly, the expiration of the Farm Bill as of September 30, 2024, leaves its future uncertain, potentially impacting federal regulation of hemp in the coming years.