Experts Debate Safety of Cannabinoid Nanoemulsions in Food and Beverages

Dr. Douglass, like Dr. White, stresses the gaps in understanding that surround the emerging technology of nanoemulsions.

“Lack of evidence isn’t evidence of lack,” Dr. Douglass says. “I tend to give some credence to anecdotal reports if they happen over and over again. That window of uncertainty between what we know and what we don’t know, there’s probably some important effect.”

Wani notes that there are still questions surrounding how, for example, nanoparticles are excreted. “Because nanoemulsions are fabricated from food-grade materials, the materials should normally be excreted in urine,” he says. “However, because of their extremely small size, they could evade the xenobiotic pathways and could be accumulated in various tissues or organs. Besides, they could find a way across the blood–brain barrier and cause effects that are still a mystery.”

All four scientists stress the importance of continuing to develop new information to better understand nanoemulsion safety. Dr. McClements says, “It is important to carry out toxicity studies,” as with any new food.

As the most skeptical of the technology, Dr. White goes furthest, saying “I think it is important to have rigorous standards for safety testing given how little we know about nanoemulsions in general, and products using nanoemulsions should be subject to additional testing. It is not sufficient to test the nanoemulsion without active ingredient and test the active ingredient without the nanoemulsion; you have to test them separately and together.”

Yet, she concludes on the note with which Dr. Douglass most agrees, saying, “From a consumer transparency perspective, I think that products using nanoparticles should include that on the label so that consumers may make informed choices.”

“If I do have concerns about the use of emulsions in cannabis beverages,” says Dr. Douglass, “it’s the lack of transparency in labelling. That’s a lot easier to enforce when you have an experienced regulator like Health Canada overseeing things, rather than [U.S.] state-based regulators.”