Summary
What is already known about this topic?
Tetrahydrocannabinol (THC), a psychoactive component of Cannabis sativa, including hemp varieties, is becoming more common in consumer products.
What is added by this report?
From October 22 to 24, 2024, over 85 individuals, aged between 1 and 91, consumed food from a Wisconsin restaurant and exhibited symptoms related to THC intoxication. The restaurant, located in a shared kitchen space, unknowingly used THC-infused oil that was intended for another vendor making edible THC products when they ran out of regular oil.
What are the implications for public health practice?
Healthcare professionals should be vigilant about potential mass THC intoxication incidents through food consumption.
Abstract
THC, a psychoactive component derived from Cannabis sativa, is increasingly included in various consumer food items. On October 24, 2024, local emergency services in Wisconsin informed Public Health Madison & Dane County (PHMDC) about transporting seven individuals from the same restaurant, all exhibiting symptoms like dizziness and anxiety. Further investigation revealed these individuals had all eaten food from this establishment shortly before their symptoms emerged. The restaurant had used oil from an adjacent cooperative kitchen that contained THC. PHMDC launched a symptom and food questionnaire, identifying 85 cases of THC intoxication linked to food consumed at the restaurant. Public health officials highlight the need for clear labeling and secure storage of THC-containing ingredients to minimize accidental exposure.
Investigation and Results
THC is found in Cannabis sativa, with generally lower concentrations in hemp. Following reports of symptoms among customers on October 24, local emergency services investigated and determined that all individuals had dined at the same restaurant. They conducted testing for carbon monoxide at the restaurant and found no issues. Later, one of the restaurant’s customers reported a positive THC test without knowing they had consumed THC. Upon this finding, PHMDC started an outbreak investigation. The restaurant owner, once informed of the illnesses, acted quickly to close their establishment. It was discovered they had used oil from a cooperative vendor known for making THC-infused products. The police were notified, and it was concluded that the THC inclusion in food was unintentional, so no criminal charges were filed. The restaurant reopened on October 26 after necessary cleaning procedures.
Public Health Response
On October 24, PHMDC launched a food and symptom questionnaire, requesting impacted customers to share their experiences. Those who sought medical attention were contacted to complete the questionnaire. Over the span of October 24 to 30, PHMDC received a total of 208 responses, with several being excluded due to incomplete information. The valid responses indicated 85 cases of THC intoxication, with symptoms starting within a few hours of eating the implicated food. Public health officials issued alerts advising against consuming leftovers from the restaurant, initially targeting pizza and later expanding to include other menu items.
Discussion
Out of the 85 people who reported symptoms consistent with THC intoxication after eating at the restaurant, 15 confirmed a positive THC test. While there was no testing conducted on leftover food or the oil used, concerns remain regarding THC’s legality in food products. As more THC-infused items enter the market, the risk of unintentional consumption increases. The presence of food facilities alongside those producing THC products raises concerns over accidental contamination. It is essential for healthcare providers and public health professionals to recognize THC intoxication as a possibility when patients present with symptoms like dizziness or anxiety.
Acknowledgments
Thanks to individuals who filled out the outbreak questionnaire and contributed to the investigation efforts.
References
- Food and Drug Administration. FDA warns consumers about accidental ingestion by children of food products containing THC. Silver Spring, MD: US Department of Health and Human Services, Food and Drug Administration; 2022.
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