What Cannabis Companies Need To Know About Work-Related Asthma (Op-Ed)

“The cannabis industry’s unique exposures and the documented health concerns are likely to accelerate regulatory action and litigation risk.”

By Erin Bass, Amy Rubenstein and Julie Vanneman, Dentons

The legal cannabis industry employs more than 440,000 full-time workers across the United States (not including hemp industry employees). As legalization spreads, so do regulatory and workplace safety challenges.

A recent multi-state study led by public health agencies in California, Massachusetts, Michigan and Washington, and supported by the National Institute for Occupational Safety and Health (NIOSH), provides the most comprehensive look yet at work-related asthma in the cannabis sector.

The findings highlight evolving health concerns, and that cannabis operators should review their safety and compliance measures.

What the Data Show: Exposures and Evolving Health Concerns

From the time of legalization in each state through 2023, 30 confirmed cases of work-related asthma were identified among cannabis industry workers. Most cases involved young (ages 18-34), male workers, in indoor cultivation or processing roles. Notably, two fatalities were directly linked to occupational asthma in cannabis facilities.

The most frequently reported exposures were:

• Cannabis plant dust and marijuana plant material (by far the majority of reported cases);
• Mold and other microorganisms;
• Cleaning and disinfecting products (notably those containing hydrogen peroxide, peracetic acid or bleach); and
• Physical factors (humidity, heat, cold).

Most cases occurred within the first three years of employment, and half developed symptoms within the first year. In all cases, there was a relationship between symptoms and work, where symptoms increased with workplace exposure and decreased without it.

Regulatory and Legal Implications: OSHA, Workers’ Compensation and Beyond

The study’s findings have immediate compliance implications for cannabis operators.

First, rising case numbers could drive increased Occupational Safety and Health Administration (OSHA) and state-level attention. While cannabis operators are familiar with oversight from state cannabis compliance agencies, it is crucial for them to recognize that they also face regulatory scrutiny from occupational safety and health agencies.

The new report emphasizes the importance of acknowledging the well-known hierarchy of occupational safety and health controls and implementing appropriate responses in the cannabis context.

• The most effective control is elimination. While it is impossible to eliminate any hazards from cannabis itself, it is possible to eliminate certain other hazards, such as exposure to particularly concerning disinfectants, and to minimize exposure to mold. Further, a job hazard analysis could identify processes that generate high levels of dust and prioritize interventions accordingly.
• The next step in the hierarchy of controls is engineering controls, including steps such as installing local exhaust ventilation and HEPA filtration.
• Administrative controls are next. In this context, procedures could be adjusted to limit personnel access to high-dust areas and provide education on the potential hazards of cannabis dust.
• Finally, personal protective equipment (PPE) could be deployed. Initiatives to require respirators could be considered during or after the implementation of engineering controls.

Further, medical surveillance programs could identify symptoms early and provide for job reassignment or medical removal as needed. Regulators are expected to scrutinize respiratory hazard controls, training and medical surveillance programs in light of the findings.

Second, workers’ compensation programs could be impacted. Only about half of affected workers filed claims, and half of those were denied—often due to insufficient clinical documentation or under-recognition of the cannabis industry’s particular hazards. Employers should anticipate more claims and potential litigation as awareness grows.

Third, employers must consider their obligations to provide reasonable accommodations under the Americans with Disabilities Act (ADA) and state law analogs. A cannabis allergy may qualify as a “disability” under the ADA. Thus, if an employee presents with a cannabis allergy that impacts her ability to perform her job, an employer has a duty to engage in the interactive process with the employee to determine if there are reasonable accommodations that would enable the employee to perform the essential functions of her job. Potential accommodations could include providing the employee with PPE or transferring the employee to another position.

These inter-related issues may appear all at once for a cannabis employer. For example, an employee with concerns about work-related asthma could file a workers’ compensation claim, seek an accommodation in the workplace and submit a complaint to OSHA. Even if the employer promptly offered a reasonable accommodation that was acceptable to the employee, such as transfer to a different position, OSHA could still decide to investigate. A citation resulting from the investigation could include a call for abatement measures that involve workplace changes beyond those already implemented in response to one employee’s complaint.

Practical Steps for Cannabis Operators

Effective compliance and risk mitigation strategies can prevent or help minimize employer liability and can positively impact employee health outcomes. Operators and associated parties should consider the following practical steps summarized below.

1. Conduct a Job Hazard Analysis: Identify high-risk tasks (e.g., grinding, trimming, cleaning) and prioritize controls.
2. Upgrade Ventilation and Dust Controls: Install local exhaust and HEPA filtration in processing areas.
3. Review and Substitute Cleaning Chemicals: Avoid asthma-sensitizing disinfectants where possible.
4. Implement Comprehensive Training: Educate workers on respiratory hazards, symptom recognition and reporting procedures.
5. Establish Medical Surveillance: Partner with occupational health providers to monitor for early signs of work-related asthma.
6. Document and Respond to Incidents: Maintain detailed records of exposures, symptoms and corrective actions.

Looking Ahead: Heightened Scrutiny and Evolving Standards

The cannabis industry’s unique exposures and the documented health concerns are likely to accelerate regulatory action and litigation risk.

Proactive compliance—mirroring best practices in other high-risk industries—will be essential to protect workers and limit liability. Early recognition and intervention, robust hazard controls and a strong safety culture are critical to preventing work-related asthma and ensuring the long-term health and productivity of the cannabis workforce. As with many other emerging regulatory issues these bellwether cases may predict a trend in occupational health.

Erin Bass is a partner in Dentons US LLP’s Employment and Labor practice. Amy Rubenstein is a partner in the Health Care practice. Julie Vanneman is a shareholder in Dentons Cohen & Grigsby’s Environmental practice.

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