This article was originally published in Life Science
By Dr. Melanie Doyle-Eisele, Senior Director of Life Sciences and Head of Federal Business Development, on behalf of Lovelace Biomedical
Early research offers insight, but major gaps remain in understanding long term respiratory effects
The rapid rise of CBD vaping products has outpaced the science and regulatory frameworks needed to fully understand their health implications. While early research provides useful insight into how cannabidiol (CBD) behaves in the body, the broader issue extends well beyond these studies.
CBD is often perceived as a lower-risk compound, particularly when compared to nicotine or other inhaled substances. However, vaped inhalation introduces a distinct exposure route, and the safety profile of CBD when vaporized and delivered to the respiratory system remains incompletely characterized. The result is a growing disconnect between widespread use and scientific clarity.
What is emerging is a complex intersection of pharmacology, product variability, consumer behavior, and regulatory uncertainty that raises important questions for researchers, policymakers, and public health professionals.
These questions have become even more timely as regulators continue to evaluate emerging inhaled products. The FDA’s authorization in May 2026 of certain fruit-flavored vaping products for adult use [3] highlights the ongoing challenge of balancing product access, consumer demand, and public health protection. Other jurisdictions are moving on different timelines and in different directions, which adds a further layer of complexity for manufacturers, researchers, and consumers operating across markets.
While that decision focused on nicotine-containing products, it underscores a broader reality: innovation in inhalable products is often advancing more quickly than the scientific evidence needed to fully understand long-term health effects. As CBD vaping products become increasingly available, ensuring that research keeps pace with product development will be critical.
The Dose Makes the Poison
At the center of this discussion is a fundamental toxicological principle often attributed to Paracelsus: the dose makes the poison. This concept is especially relevant in the context of CBD vaping, where real-world use patterns vary widely. Controlled studies frequently rely on high exposure levels to identify potential hazards, but actual human consumption would rarely reach those extreme exposure levels.
In practice, some individuals might use these products occasionally, while others may vape multiple times per day, leading to substantially different internal exposures. Repeated use over time may alter how the body absorbs and metabolizes CBD and its byproducts, potentially influencing toxicity in ways that are not captured in controlled experimental settings.
Understanding how dose translates into biological effect across real-world scenarios remains a critical gap. Without this context, it is difficult to define meaningful safety thresholds or provide evidence-based guidance to consumers.
What Research Reveals and What It Cannot Yet Explain
Scientific investigations into inhaled CBD have begun to establish a foundational understanding of its pharmacokinetics and toxicity profile. Evidence from controlled inhalation studies indicates that CBD is rapidly absorbed through the respiratory tract and quickly metabolized into several byproducts. [1]
At elevated exposure levels, observed effects tend to concentrate in the upper respiratory system, particularly in nasal tissues. [2] This pattern suggests that, under certain conditions, effects at the portal of entry may be a greater concern than systemic toxicity. The lungs and other organs appear to show fewer pathological changes in these models, although this does not eliminate the possibility of long-term or cumulative effects.
At the same time, these findings highlight important limitations. Most studies isolate CBD in relatively simple formulations, which does not reflect the complexity of commercial products. In addition, high-dose experimental designs are not intended to replicate typical human use. As a result, the data provide valuable signals of potential risk but do not yet offer a complete picture of real-world safety. More importantly, these limitations make it difficult for regulators, healthcare providers, and consumers to determine how existing findings should inform real-world decision making.
Formulation Matters: A Complex Chemical Landscape
One of the most significant challenges in evaluating CBD vaping lies in the variability of product formulations. Unlike pharmaceutical products, which are tightly controlled, CBD vape liquids often contain a mixture of ingredients that can differ widely across manufacturers.
These formulations may include carriers such as propylene glycol, as well as flavorings and other additives that have not been thoroughly evaluated for inhalation safety. Each component introduces its own set of variables, particularly when heated and aerosolized.
This lack of standardization makes it difficult to generalize findings from one product to another. It also complicates efforts to identify which components are responsible for observed health effects, creating uncertainty for both researchers and regulators.
Lessons from the Past: Regulation Lagging Behind Innovation
The current regulatory environment surrounding CBD vaping reflects a familiar pattern. Historically, inhaled products such as traditional cigarettes and electronic nicotine delivery systems entered the market with limited oversight. Regulatory frameworks developed gradually over time, often in response to emerging scientific evidence and public health concerns.
CBD vaping appears to be following a similar trajectory. It may take decades for regulations to fully catch up, due to both scientific uncertainty and competing economic interests. In the meantime, manufacturers retain considerable flexibility in designing and marketing their products.
It also limits the ability of public health agencies to establish consistent safety standards, leaving consumers to navigate a marketplace that is regulated inconsistently across jurisdictions.
Flavorings, Marketing, and Population Risk
Among the many variables in CBD vaping, flavorings represent a particularly important concern. Many flavoring agents were originally developed for ingestion, not inhalation, and their safety when vaporized remains uncertain. When combined with appealing packaging and branding, these products may also attract younger users.
This trend mirrors earlier patterns seen in the e-cigarette market, where flavor diversity and marketing strategies played a significant role in youth uptake. Although age restrictions are typically in place, enforcement can be inconsistent, and the perception of CBD as a benign or therapeutic substance may further contribute to its appeal.
Recent regulatory decisions surrounding flavored vaping products have only heightened the importance of this issue. As policymakers weigh potential benefits for adult users against broader population-level risks, understanding the respiratory effects of ingredients, additives, and flavoring compounds becomes increasingly important.
Understanding which populations are most at risk, and why, is an essential component of the broader public health conversation.
Key Gaps That Demand Further Study
Despite growing interest and research activity, several critical questions remain unanswered:
- How do low to moderate exposure levels affect the respiratory system over time?
- What role do CBD metabolites play in driving observed biological effects?
- How do different formulations and additives influence toxicity?
- What are the long-term consequences of repeated inhalation?
- How do real-world use patterns alter pharmacokinetics and risk profiles?
These questions directly affect the ability of healthcare providers to counsel patients, regulators to develop evidence-based policies, and consumers to make informed decisions about product use.
One of the most pressing challenges is that consumers are rarely inhaling CBD alone. Many products contain carrier compounds, flavoring agents, terpenes, and other additives that may contribute to respiratory effects independently or in combination with CBD. Determining which components drive observed biological responses remains a significant research priority.
At the same time, substantial variability among devices, formulations, heating temperatures, and user behaviors makes it difficult to compare findings across studies or establish meaningful safety thresholds. Without a clearer understanding of how these factors interact, knowledge gaps will continue to hamper efforts to accurately assess risk.
Addressing these questions will require more than incremental research. It will require coordinated efforts across disciplines, as well as study designs that better reflect the diversity of products and real-world patterns of use.
Moving Forward in the Face of Uncertainty
The conversation around CBD vaping is not limited to a single compound or study. It represents a broader challenge in evaluating emerging inhaled products in a rapidly evolving marketplace. While current evidence suggests that some effects may be localized and dose dependent, the absence of long-term and formulation-specific data limits the ability to draw definitive conclusions.
In this context, uncertainty should not be interpreted as safety. Instead, it should serve as a call for more targeted research. Closing the most important knowledge gaps, including the effects of chronic exposure, formulation-specific risks, and the role of additives and flavoring compounds, will be essential if science is to keep pace with product innovation.
Author Bio
Dr. Doyle-Eisele is Senior Director of Life Sciences and Head of Federal Business Development at Lovelace Biomedical, where she oversees the major research areas of the Applied Sciences Division. Her background is in inhalation toxicology, pharmacokinetics and pharmacology, with specialist capability in pulmonary disease, infectious disease, inflammation and injury. Her work spans drug development from early model evaluation through to Investigational New Drug and New Drug Application submissions and Emergency Use Authorizations.
References:
- Schwotzer D, Kulpa J, Trexler K, Dye W, Jantzi J, Irshad H, Ware MA, Bonn-Miller M, McDonald J, Lefever T. Pharmacokinetics of Cannabidiol in Sprague-Dawley Rats After Oral and Pulmonary Administration. Cannabis and Cannabinoid Research. 2023;8(2):360 to 373. https://doi.org/10.1089/can.2022.0121
- Schwotzer D, Kulpa J, Gigliotti A, Dye W, Trexler K, Irshad H, Lefever T, Ware M, Bonn-Miller M, McDonald J. Biological Response after 14-Day Cannabidiol and Propylene Glycol Inhalation in Sprague-Dawley Rats. Cannabis and Cannabinoid Research. 2025. https://doi.org/10.1089/can.2023.0132
- US Food and Drug Administration. FDA Expands Market Access, Authorizes New ENDS Products. Press announcement, 5 May 2026. https://www.fda.gov/news-events/press-announcements/fda-expands-market-access-authorizes-new-ends-products