Cannabis policies in the U.S. have seen a dramatic shift over the past few decades. Most states now allow some form of legal cannabis use, even though federal law still prohibits it. This patchwork of regulations has developed with little federal oversight and often without prioritising public health. A new report from the National Academies of Sciences, Engineering, and Medicine, titled “Cannabis Policy Impacts Public Health and Health Equity” (2024), takes a closer look at these changes, exploring their effects on public health and offering well-researched recommendations for improving cannabis policies.

The Current Policy Landscape

As of April 2024, 38 states, three territories, and the District of Columbia have legalised medical cannabis use, while 24 states have authorised adult non-medical use. This evolution began with California’s 1996 medical cannabis initiative and accelerated with Colorado and Washington’s 2012 adult-use legalisation. The report details how these changes were driven by multiple factors, including compassion for patients, skepticism about cannabis prohibition enforcement, potential tax revenue, and increasing concern about racial disparities in cannabis arrests.

The current legal framework remains complex and contradictory. Cannabis continues to be classified as a Schedule I controlled substance under federal law (though rescheduling to Schedule III has been proposed), while states have implemented varied regulatory approaches. Further complicating matters, the 2018 Agriculture Improvement Act (Farm Bill) removed “hemp” from the Controlled Substances Act, creating a largely unregulated market for hemp-derived intoxicating cannabinoids that operates nationwide.

The Evolution of Cannabis Markets and Products

The report documents significant shifts in cannabis use patterns and product types. National survey data show the prevalence of past-year cannabis use among U.S. adults nearly doubled between 2002 and 2022, from 11% to 21.9%. Perhaps most notably, by 2022, more Americans reported daily or near-daily cannabis use than alcohol use at this frequency. Meanwhile, use among youth has remained relatively stable.

Cannabis products have evolved far beyond traditional dried flower. While flower remains the most commonly used product, cannabis concentrates, edibles, and vape oils are increasingly popular, with many consumers using multiple product types. The potency of cannabis products has also increased dramatically. The average THC concentration in seized cannabis flower rose from approximately 4% in 1995 to over 12% by 2014, while concentrates typically contain 60-90% THC.

The report explains how different modes of administration—smoking, vaping, oral consumption—affect the pharmacokinetics of cannabis and its effects. For instance, inhalation delivers THC rapidly to the brain with effects felt within seconds to minutes, while oral ingestion produces delayed and prolonged effects beginning 30 minutes to 2 hours after consumption and lasting 5-8 hours.

Public Health Functions Applied to Cannabis

A central contribution of the report is its application of core public health functions—assessment, policy development, and assurance—to cannabis regulation. The committee found significant gaps in all three areas.

Assessment: Current cannabis surveillance systems are fragmented and inadequate. While various data sources exist, there is limited coordination and standardisation. The report calls for a centralised, adaptable surveillance system that would monitor cannabis cultivation, product sales, use patterns, and health impacts. Such a system would ideally include a surveillance plan, systematic data collection and analysis, regular dissemination of findings, linkage to public health action, and ongoing evaluation.

The Centers for Disease Control and Prevention (CDC) has developed a cannabis strategy, but the report notes it lacks several essential elements, including approaches to data dissemination, clear mechanisms to translate findings into action, and provisions for regular evaluation.

Policy Development

The report documents how the influence of the cannabis industry has affected regulatory decisions, with examples from multiple states where industry lobbying has successfully opposed public health protections such as pesticide restrictions and limits on THC concentration. The committee found limited safeguards against industry influence in most state cannabis regulatory frameworks.

The authors contrast U.S. approaches with more measured models in countries like Canada and Uruguay, which exercise stricter government control over cannabis products and retail. They note that most U.S. states have weak advertising restrictions, allowing extensive marketing that reaches children and promotes high-potency products.

Assurance: Quality control measures for cannabis products vary widely across states. The report recommends adoption of U.S. Pharmacopeia standards, which provide scientifically valid methods for ensuring product identity, composition, and safety.

Training requirements for retail cannabis staff are inconsistent, yet these individuals often serve as trusted sources of information for consumers. The committee recommends mandatory training covering cannabis effects, prevention of sales to minors, warnings about impaired driving, and recognition of signs of customer impairment.

Public education campaigns about cannabis risks are essential but underdeveloped in most states. The report calls for targeted campaigns directed primarily toward parents and vulnerable populations, addressing risks, harm reduction strategies, and safe storage practices.

Health Equity Considerations

One of the report’s most significant contributions is its examination of how cannabis policies affect health equity. The authors analyse three key dimensions: criminal justice impacts, social equity programs, and effects on social determinants of health.

Criminal Justice Impacts

The historical enforcement of cannabis prohibition has disproportionately harmed communities of color. The report notes that racial disparities in cannabis arrests may have actually increased during policy liberalisation, with arrests decreasing for White people while increasing for Black people between 2002-2004 and 2017-2019. These disparities contribute to health inequities, as criminal records limit economic security, employment, housing, and educational opportunities.

A major limitation in evaluating these impacts is the lack of comprehensive data on cannabis arrests and sentencing. The committee recommends that jurisdictions collect and publicly report detailed data on cannabis law enforcement, including specific violations and demographic information.

Social Equity Programs

Most states that have legalised cannabis have implemented social equity measures aimed at helping communities harmed by cannabis prohibition. These programs typically include criminal justice reforms (record relief, resentencing), technical and financial assistance for cannabis businesses, and community reinvestment initiatives.

While well-intentioned, these efforts face implementation challenges. The report emphasises the need for systematic evaluation and revision of social equity policies to ensure they meet their goals without unintended consequences. It specifically recommends automatic expungement or sealing of records for low-level cannabis offenses, noting that petition-based relief systems have proven less effective.

Social Determinants of Health

Cannabis policies affect numerous social determinants of health, including economic stability, education access, healthcare access, neighborhood environments, and social contexts. The report raises concerns that cannabis retailers may be disproportionately located in lower-income communities or communities of color, potentially contributing to health inequities.

Healthcare access is another critical area. The report notes that punitive policies regarding prenatal drug use exist in nearly half of U.S. states, and drug testing in pregnancy is applied inequitably, particularly to communities of color. This may deter pregnant cannabis users from seeking prenatal care, potentially worsening health outcomes.

High-Potency Products and Research Needs

A particular focus of the report is the public health implications of high-concentration THC products. The authors note that the risks associated with THC consumption increase with dose, and legalising high-potency products potentially increases cannabis-related harms. Products containing high THC concentrations have been associated with greater risk of psychosis and cannabis use disorder.

The committee found that more research is urgently needed to understand the relationship between THC dose and adverse effects. It developed a comprehensive research agenda focused on:

1. Public health outcomes of different regulatory approaches
2. Efficacy of tests for cannabis impairment
3. Health effects of cannabis use in specific populations (pregnant persons, youth, veterans, older adults)
4. Health risks of emerging synthetic and semisynthetic cannabinoids
5. Effectiveness of risk mitigation strategies

The Path Forward

The report makes clear that better application of public health principles to cannabis policy is essential as legalisation continues to spread. The committee offers specific recommendations for federal agencies, state regulators, and other stakeholders:

The CDC should develop best practices for protecting public health in states with legalised cannabis, drawing from tobacco and alcohol policies. These should address marketing restrictions, age limits, retail regulations, taxation, product design, and measures to limit youth access.

Congress should refine the definition of “hemp” to clarify that intoxicating cannabinoids are not exempt from the Controlled Substances Act, addressing the regulatory gap that has allowed unregulated intoxicating products to proliferate.

State cannabis regulators should require training for retail staff and adopt U.S. Pharmacopeia standards for product quality and safety. The report also calls for Congress to remove restrictions that prevent the Office of National Drug Control Policy from studying cannabis legalisation impacts.

Historical Context and Enforcement Patterns

The report provides valuable historical context for understanding current cannabis policies. It traces state cannabis control policies from the 1860s through today, noting that states have historically led the way in cannabis regulation, with federal policies generally following rather than preceding state action.

Particularly informative is the analysis of enforcement patterns over time. Cannabis arrests reached unprecedented levels between 1992 and 2007, driven primarily by possession offenses and marked by significant racial disparities. This period also saw an increase in collateral consequences for drug convictions, including restrictions on access to education, housing, and public benefits.

The committee notes parallels with alcohol prohibition and its repeal, while acknowledging important differences. Unlike alcohol legalisation, which occurred with formal federal approval, state cannabis legalisation exists in tension with federal law. Additionally, alcohol regulation initially included strict controls designed to moderate consumption, while cannabis markets are emerging in a less restrictive regulatory environment.

Methodological Approach and Evidence Review

The committee conducted a thorough evidence review of the public health impacts of cannabis policy, examining 14 systematic reviews. This analysis found limited or suggestive evidence that perceived risk of cannabis use declines after legalisation, adult use increases, traffic collisions increase, and cannabis-related hospital visits increase. For all other outcomes, evidence was judged insufficient.

This cautious assessment reflects the challenges of studying rapidly evolving policies with varying implementation across jurisdictions. The report emphasises the need for better data collection, improved policy analysis databases, and enhanced surveillance systems to support rigorous evaluation of policy outcomes.

Future Implications of Federal Policy Changes

The report discusses potential implications of rescheduling cannabis from Schedule I to Schedule III under the Controlled Substances Act, a change currently under consideration. While rescheduling would reduce research barriers and might affect tax treatment of cannabis businesses, it would not legalise cannabis federally or automatically legitimise state programs.

The authors note that rescheduling would create additional policy complexity. Schedule III substances require FDA approval before prescription, with regulatory requirements that differ significantly from current state medical cannabis programs. How rescheduling would impact these programs remains uncertain and would depend on FDA implementation and court interpretations.

The National Academies report represents the most comprehensive assessment of cannabis policy through a public health lens in decades. It demonstrates that while cannabis legalisation has proceeded rapidly, attention to public health considerations has lagged. By applying core public health functions to cannabis policy and centering health equity concerns, the report provides a framework for developing more effective approaches to cannabis regulation that protect public health while addressing historical injustices.

Source National Academies

A randomized, placebo-controlled, double-blind, pilot study of cannabis-related driving impairment assessed by driving simulator and self-report

Abstract

Aims: In the context of increasing cannabis use, understanding how cannabis affects specific driving behaviors is crucial in mitigating risks and ensuring road safety.

Design and setting: The current study included 38 adults aged 18–40 years, administered a single 0.5 g acute dose of vaporized cannabis (5.9% Tetrahydrocannabinol (THC), 13% THC or placebo) in a randomized, within-subject, double-blind, counterbalanced design. Throughout each of the three, 8-h assessment days, at 4 time points, participants underwent simulated driving tests, including lane-keeping, car following, and overtaking tasks, capturing 19 behavioral metrics. An SPSS linear mixed model assessed the main effects of dose, time, and dose × time.

Findings: During lane-keeping, participants exhibited reduced steering reversal rates up to 5.5 h following 13% THC and 3.5 h for 5.9%. For car following, participants showed reduced pedal peak-to-peak deviation and reversal rates, persisting for 1–3 h post-dose (only at 13% THC). During overtaking, following 13% THC, subjects demonstrated a shorter median gap to passed cars, lower time-to-potential collision, and more time in the oncoming lane. Drug effects on driving metrics improved gradually, to varying degrees over time. Approximately 66% of participants reported willingness to drive, despite subjective awareness of being impaired and objectively worse driving performance.

Conclusions: Our study reveals for the first time long-lasting cannabis-induced impairments across multiple driving behaviors, that extend beyond the typical 3-h window explored in most previous research. The observed discrepancy between participants’ willingness to drive and their actual impairment highlights an important public safety concern. In addition, the lack of correlation between cannabinoid metabolite concentrations and driving performance challenges the reliability of blood THC levels as impairment indicators, emphasizing the need for a multifaceted approach to assessing cannabis-impaired driving risk. (Source: Journal of Psychopharmacology)

Also see

• Effects of cannabis on visual function and self-perceived visual quality
• Cannabis (THC) messes with your Executive Functions – Can disrupt and impede good decision making and add to dysregulation
• Cannabis and Driving: Victorian Law Change for ‘Medicinal’ Cannabis Users – But is Road Safety Seriously Compromised?
• ‘Medicinal’ Cannabis & Driving – Is it an Issue? (DRR)

Cannabis use is becoming increasingly common worldwide, with growing accessibility due to global legalisation trends. However, with rising use comes significant risks, particularly in relation to cannabis use disorder (CUD). Recent studies reveal that individuals requiring hospital-based care for CUD face an alarmingly high risk of mortality within five years. This blog explores the findings, the factors contributing to these risks, and why addressing cannabis use disorder mortality is crucial.

What is Cannabis Use Disorder?

Cannabis use disorder (CUD) refers to problematic cannabis use that results in significant impairment or distress. It ranges from dependency issues to difficulty stopping usage despite harm to daily life and health. While cannabis is often perceived as “safe,” emerging evidence suggests the contrary when it comes to chronic consumption and addiction.

Why Cannabis Use Disorder Mortality Matters

A large-scale study conducted in Ontario, Canada, involving 11.6 million individuals, highlights that hospital-based care for cannabis use disorder is a significant risk marker for premature death. Within a five-year follow-up period, individuals treated for CUD were at a 2.8 times higher risk of mortality than the general population. The most significant causes of death included suicide, trauma, and opioid poisoning.

These findings demonstrate that cannabis use, particularly when it progresses to disorder levels requiring hospitalisation, is not without serious, life-altering, and often life-ending consequences.

Cannabis Use Disorder Mortality by the Numbers

To truly comprehend the gravity of the situation, here are some key figures from the study:

• Of 527,972 individuals included, 106,994 had an incident of hospital-based CUD care.
• Within five years, 3.5% of individuals with hospital-treated CUD died, compared to just 0.6% of the general population.
• Specific mortality risks were exacerbated for:
  • Suicide: 9.7 times higher risk
  • Opioid poisoning: 5.03 times higher risk
  • Trauma-related deaths: 4.55 times higher risk
  • Lung cancer: 3.81 times higher risk

With rates like these, it’s clear that cannabis use disorder mortality is a significant public health challenge that warrants urgent attention.

Causes of Increased Mortality in Cannabis Use Disorder - High-Risk Behaviours and Comorbidities

Many individuals with cannabis use disorder engage in high-risk behaviours that exacerbate other health risks. These include high levels of tobacco consumption, alcohol dependency, and polysubstance use, all of which contribute to increased mortality rates.

CUD is also strongly associated with severe mental health conditions such as schizophrenia, bipolar disorder, and depression. These comorbidities not only make treatment challenging but often compound the likelihood of complications like suicide or accidental overdoses.

Physiological Effects of Chronic Cannabis Use

Cannabis use itself is not without direct health consequences. Tetrahydrocannabinol (THC), the active compound in cannabis, has been linked to long-term cardiovascular risks, including heart disease. Additionally, chronic exposure to cannabis smoke increases the risk of respiratory illnesses and lung cancer.

Social and Structural Determinants

From access to adequate healthcare to financial instability, social determinants of health also play a role. Many individuals with cannabis use disorder come from socio-economically disadvantaged communities, further compounding the mortality risk.

Cannabis Use Disorder Compared to Other Substance Disorders

While the risks associated with cannabis use and CUD are severe, how does it compare to other substance use disorders like alcohol, stimulants, or opioids? The study found that:

• Individuals with alcohol use disorder have a 1.3 times higher risk of mortality than those with CUD.
• Those with stimulant use disorder had a 1.69 times higher risk, and
• Those with opioid use disorder faced a 2.19 times higher risk.

However, the key takeaway here is the rapid growth of CUD diagnoses worldwide, driven by more frequent and high-potency cannabis use. This trend means more individuals than ever are at risk, and the overall public health impact of CUD could climb rapidly.

The Broader Context of Cannabis Use

The legalisation and commercialisation of cannabis have made the substance accessible to more people, often under the assumption that it is benign. However, this shift has also led to higher rates of regular and heavy consumption, increasing the prevalence of cannabis use disorders.

A Volatile Public Perception - Cannabis’ perception as a “safe” drug contributes to complacency. This belief may prevent individuals from adequately addressing early signs of problematic use. The data says otherwise, with mortality risks linked to hospital-based CUD matching or exceeding those for other substances in several critical areas.

What Needs to Be Done to Address Cannabis Use Disorder Mortality

The findings of the study underscore the need for preventive and policy measures to mitigate the risks associated with cannabis use disorder. While addressing the complex ecosystem of harm requires nuanced interventions, some immediate areas for focus include:

• Strengthening Early Detection Efforts: Identifying CUD early can prevent escalation into more severe stages requiring hospitalisation.
• Educating the Public: Combat the misconception that cannabis use, particularly habitual and high-potency use, is harmless.
• Access to Appropriate Treatment: Expand access to mental health, addiction treatment, and support services for individuals struggling with CUD and other co-occurring substance dependencies.
• Policy Development: Address legal loopholes that allow the unchecked commercialisation of high-potency cannabis products.

A Need for Proactive Action

The sobering reality is that cannabis use disorder isn’t just a problem for the individuals directly impacted—it’s a growing public health issue. The dramatic increase in hospitalisations and mortality rates related to CUD reflects wider trends in substance use and mental health that require immediate attention.

If you or someone you know is struggling with problematic cannabis use, seeking support early could save a life. Together, we can work toward a healthier, safer future. 

(Source: Jama Network)

The system uses a saliva collection device to test impaired drivers for marijuana use as well as other drugs.

Over the last year, a group of officers with the Minnesota State Patrol carried a new piece of equipment in their squad cars. It looked like a Keurig machine, only this device doesn't make coffee; It analyzes saliva for THC — the chemical in marijuana that makes people high.

The machines were part of a pilot program that ended earlier this year, and the state patrol is preparing its results for state lawmakers. Minnesota is one of several states where police have tried this tool. They're doing so in response to changing behaviors: Most Americans now live in a state where marijuana is legal, more people are using it, and millions are doing so before driving.

Every state has a law that prohibits driving under the influence of drugs in some way, whether it be setting a permissible limit for legal drugs or not allowing any amount, but marijuana is difficult to regulate, and states are grappling with how to prevent people from driving under the influence.

"Essentially we've let the horse out of the barn," says Pam Shadel Fischer, senior director of external engagement with the Governors Highway Safety Association. "We need to make sure that we have things in place to protect others in the event that someone chooses to consume cannabis and get behind the wheel and be impaired."

Studies show THC can impair driving. It slows down driving speeds and reaction times and makes people swerve. Yet that varies widely by a person's tolerance to the drug, and the data is unclear on how big a problem driving while high actually is. In Colorado, for instance, fatal car crashes where a driver had THC in their blood went up after legalization. But it's difficult to determine whether a person was actively high at the time they crashed.

"When it comes to alcohol, the breath alcohol level is correlated very strongly with your blood alcohol level, which is correlated very strongly with your brain alcohol level," says Cinnamon Bidwell, an associate professor of psychology and neuroscience at the University of Colorado Boulder.

In other words, an alcohol breathalyzer is a good stand-in for how drunk and impaired a person is, but THC can stay in a person's system for hours, or even days, after they are no longer high.

"Can we detect THC accurately and reliably? The answer is yes. We can detect it in saliva. We can detect it in blood. We're working on reliable ways to detect it in breath," Bidwell says. "But what does that mean? And is there a level that means somebody recently used or that somebody is actively impaired? The data aren't there yet."

Without that, she says states risk over-punishing people who do use but don't drive while high.

Researchers, private companies and state governments are racing to find a tool that detects marijuana impairment with the ease and reliability of the alcohol breathalyzer.

In addition to Minnesota, officers in Alabama, Indiana, Michigan, Colorado and Wisconsin use or have piloted saliva tests. In Missouri, police have tested goggles that measure a driver's pupil size and movement. In Colorado, Bidwell is part of a team of researchers studying THC breathalyzers. In Vermont and Illinois, researchers have developed apps that could test a person's cognitive abilities roadside.

"We're all circling around the same question, which is, did you use recently?" says Ashley Brooks-Russell, an associate professor at the Colorado School of Public Health. "If someone's done something to cause a crash or be pulled over for a DUI, we want to know, are they impaired?"

Col. Matthew Packard, chief of the Colorado State Patrol, says with or without a test to back officers up, it's crucial to teach them what to look for. A test, he says, is just another tool.

"All that is, is confirming or supporting what you saw on the roadside," he says. "To use an ice cream analogy, the test is kind of like the cherry on the top, but ice cream is still great even if it doesn't have whipped cream and cherry." (for complete article  NPR)

Also see Cannabis and Driving: Victorian Law Change for 'Medicinal' Cannabis Users – But is Road Safety Seriously Compromised? - WRD News

Key Takeaways

• Data from over 222,600 mother-child pairs were analysed in this linkage cohort study.
• This study examined maternal cannabis use disorder (CUD) and the risk of disruptive behavioural disorders (DBDs) in offspring.
• Children exposed to maternal CUD had a 3-fold increased risk of behavioural disorders after adjusting for covariates, suggesting CUD as an independent predictor of childhood DBD risks.
• Results emphasise the need for interventions to reduce cannabis use among reproductive-age women.

Cite https://doi.org/10.1016/j.psychres.2025.116404Get rights and content

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