Results from this study indicate that the time period immediately preceding the manufacturer-initiated recall (a period when the US FDA, America’s Poison Centers, and CDC identified initial concerns about illnesses associated with consuming these products and actively provided updates to the public) had a relatively high number of product advertisements available across multiple parts of the internet that likely led to high consumer exposure to these products. Following the recall notification, the number of online access points appeared to decrease; however, we nevertheless identified at least 47 active sellers across social media, cannabis e-commerce, and website platforms.

Similar to prior studies examining online availability of psilocybin [12], there were a high number of continued access points that originated from search engine results that linked to websites selling direct-to-consumer products, two-thirds of which were found to be actively advertising even during the post-recall period. For approximately one-third of those websites, we were able to successfully complete a simulated test purchase, and some vendors actively reached out through email seeking to complete a cancelled order we initiated through this process.

The Diamond Shruumz product recall notification exemplifies some of the ongoing challenges of consumer harms associated with new and emerging substances that become readily available on the internet; in this case, novel edible mushroom-containing nootropics. This incident also has a similar fact pattern to the 2019 outbreak of e-cigarette or vaping product use–associated lung injury, which ended with a total of 2807 hospitalized cases (68 of which were deaths) attributed to vitamin E acetate in tetrahydrocannabinol (THC)-containing nicotine products [12]. In the case of Diamond Shruumz, interest in psychedelics and psilocybin therapy is growing [13-15], though psilocybin remains illegal, and products mimicking psychedelic effects or possibly containing microdoses of psychoactive properties appear to be available via direct-to-consumer sales, despite unknown potential health risks.

To capitalize on the growing interest but also the slow path of potential legalization of psychedelics, manufacturers may be experimenting with undeclared and unlabeled synthetic analogues for human consumption, such as 4-acetoxy-DMT [316]. Further, the FDA has warned food manufacturers that A. muscaria’s extracts and certain constituents, as found in Diamond Shruumz samples tested by the FDA, do not meet Generally Recognized as Safe (GRAS) standards, are not authorized for use as ingredients in foods, and may be harmful [217]. Alarmingly, Diamond Shruumz products also included appealing marketing of diverse edible forms (eg, gummies, bars, cones) and flavors (eg, chocolate, birthday cake, various fruit flavors) found with other increasingly publicly acceptable substances, such as cannabis and nicotine products, which may be attractive to children and young adults [18].

Continued availability of these products, which we observed in the early stages of initiation of this recall, highlights the challenges of effectuating recalls in a diverse e-commerce landscape for a novel product that has legal ambiguity (ie, A. muscaria is legal and 4-acetoxy-DMT is unscheduled, but DMT and psilocybin are scheduled and prohibited by the US Drug Enforcement Administration). Reflecting these challenges, the FDA announced that it was working with the National Association of Convenience Stores and the National Smoke Shop Association to raise consumer awareness about the recall and warn consumers about purchasing or consuming Diamond Shruumz [219-21undefinedundefined].