The Euphoric Mix of Blockchain and Marijuana

By Dr. Tom Keenan

Tech Style

What do cannabis and blockchain have in common, aside from being smoking-hot topics in Canada right now? One answer is that managing legal cannabis raises big problems and the blockchain might provide big answers.

We know from Canada’s experience with medical marijuana that meticulous “seed to sale” tracking is vitally important. This could be a tailor made application for blockchain, which is essentially a distributed ledger that’s hard to fudge.

Blockchain is the basis for cryptocurrencies such as Bitcoin, which has a publicly viewable ledger that anyone can check. There are people all over the world making sure that if you spend a Bitcoin (or, more likely, a fraction of a Bitcoin), you can’t spend it again.

A blockchain approach has been tested by Walmart for tracking products such as Chinese pork and Mexican mangoes. One goal is to be able to pull them off the shelves quickly in case of a recall. IBM, which is seeking to become a big player in the blockchain space, provided the technology for this through its open source Hyperledger Fabric.

I recently attended the Distributed: Health Conference in Nashville, and it was clear that health care companies are very keen on this technology. Doctors, nurses, lab technicians and pharmacists could put your health information onto a secure distributed ledger. Then, if you wanted to change doctors, or add a new one, you could simply give that person permission to access your records on the blockchain.

Of course, the devil is in the details. Who will design it? Who will build and maintain it? Researchers at the MIT Media Lab have created a pilot system called MedRec. They needed to find a way to encourage “miners” – the folks who use their computing power to maintain the integrity of the blockchain.

With Bitcoin, that incentive is pretty straightforward. Miners get a small commission, in Bitcoin of course, for their efforts. The MIT researchers suggest that health organizations might prefer their compensation in the form of anonymized data about patients that, with permission, could be used for medical research and diagnosis.

There’s something of a sweet irony in applying blockchain to track marijuana. Cryptocurrencies such as Bitcoin are still getting over their bad reputation as vehicles for the sale of illegal products, especially drugs. Law enforcement couldn’t really trace who was buying and selling contrabando in blockchain-based marketplaces such as the Silk Road. Its latest incarnation, Silk Road 3.1, sells “every type of cannabis/weed, psychedelics, opioids, ecstasy, benzos, dissociatives, prescription drugs, stimulants broken down into smaller subcategories, such as DMT, heroin, and cocaine”, according to an online user manual.

There is a certain sweet irony in the possibility that the technology that fuelled Dark Web drug dealing may soon be harnessed to bring order, structure, and, of course, the inevitable collection of taxes, to Canada’s legal marijuana industry.


Dr. Tom Keenan is an award-winning science/technology journalist and professor in the Faculty of Environmental Design at the University of Calgary

Web watch

IBM’s Hyperledger Fabric: https://www.ibm.com/blockchain/hyperledger.html

MedRec: http://dci.mit.edu/assets/papers/eckblaw.pdf

Silk Road 3.1: https://silkroaddrugs.org/guide-on-how-to-access-the-silk-road-3-0/