Canada has the world’s largest market for recreational cannabis. Its legalization last year lit the path to a ‘higher,’ more liberal future, and was a bold move that came at an opportune time for science.

Cannabis-related research and education are flourishing in this political landscape — the demand for cannabis expertise is going through the roof, creating a space that begs for attention from researchers.

But cultivating cannabis for both research and recreation comes at a cost: it is both expensive to produce at industrial scales and damaging to our environment.

With the many trailblazing studies on cannabis underway, an especially creative finding detailing a new cultivation technique was published in February as a letter in Nature. Dr. Jay Keasling’s lab at UC Berkeley engineered yeast to produce pure cannabinoids like tetrahydrocannabinol (THC) and cannabidiol (CBD). This discovery motivates a reconsideration of current cannabis production policies and strategies.

The ecological and economic costs of cultivating cannabis

A recent CTV News article titled “Canada’s largest outdoor cannabis farm ready for growth” reports that prior to the farm’s opening, most legal cannabis had been cultivated in indoor facilities.

This should be a cause for concern. The financial cost of these methods of production is superseded only by the environmental costs. The cultivation of cannabis is not only water- and nutrient-intensive, but also usually requires land clearing, causes agrochemical pollution, and erodes soil. The unenlightened idea of an outdoor farm could cause severe ecological harm and environmental degradation. 

[pullquote]The production of one kilogram of processed cannabis releases 4600 kg of carbon dioxide emissions into the atmosphere. That is the amount of carbon dioxide produced by 3 million cars in the US.[/pullquote]

An indoor facility is an even worse prospect. A 2012 study published by Dr. Evan Mills in Energy Policy, analyzed a four by four by eight-foot module of indoor cultivation. The results show that it would require 13,000 kilowatt-hours per year for utilities such as high-intensity lighting, ventilation, pre-heating the irrigation water, space heating, and air conditioning within the indoor facility. At this rate, Mills estimated the financial cost of growing cannabis from electricity alone to be $6 billion per year in the US.

The environmental costs are even more astounding — fossil fuels have caused carbon dioxide levels to be raised four times the atmospheric usual. At this rate, Mills estimated that the production of one kilogram of processed cannabis releases 4600 kg of carbon dioxide emissions into the atmosphere. That is the amount of carbon dioxide produced by 3 million cars in the US. The ecological horror entailed would cause both Greta Thunberg and anyone who understands climate change to have nightmares.

A sustainable alternative to indoor and outdoor cultivation of cannabis

The environmental burden of producing cannabis is too costly using the current methods of cultivation. It would be a great mistake on the industry’s part not to consider alternatives. One beneficial method that could help solve these problems is the procedure co-outlined by Keasling.

The new method is said to cover the deficits of current cannabis production methods. The researchers created an experimental setup that would be cost-efficient, environmentally safer, and enable direct synthesis of THC and CBD.

By developing a fermentation process using brewer’s yeast, the scientists have engineered a way to produce cannabinoids from a sugar called galactose. The process could help rein in the carbon footprint and financial cost of cannabis cultivation, as well as enable efficient production of specific cannabinoids normally found in trace amounts of plant-cultivated cannabis. 

It could be a great breakthrough for Canadian researchers studying cannabis to investigate the application of this new method, along with companies that sell products imbued with THC and CBD, such as cannabis-derived oils.

Sustainably cultivating cannabis can have medical applications

[pullquote]By developing a fermentation process using brewer’s yeast, the scientists have engineered a way to produce cannabinoids from a sugar called galactose.[/pullquote]

The efficient synthesis of THC and CBD through the sustainable yeast-based method could be especially relevant in medicine due to the effects of the isolated compounds on patients.

According to a research review on effects of THC on cognition, the compound can reduce activity in major parts of the brain, including the prefrontal cortex. THC is thus generally linked to impairment of cognitive abilities, as well as psychotic symptoms and anxiety. On the other hand, CBD, which is an antagonist of the cannabinoid receptor, increases activation of other major parts of the brain, such as the prefrontal cortex and striatum.

The review further concludes that CBD reduces anxiety, thus opposing the effects of THC. When subjects are given a combination of equal amounts of THC and CBD, in comparison to pure THC, it was observed that CBD subdued the detrimental effects caused by THC. The risks associated with CBD products are therefore thought not to be associated with CBD itself, but other cannabinoids that can be found in the product.

Controlling the THC:CBD ratio in potential medications derived from cannabis could hold promise in medical research. Dr. Lakshmi Kotra, a senior scientist at the U of T-affiliated Krembil Research Institute, illustrated the example case of Sativex in an interview with The Varsity.

Sativex is a Canadian drug that has a 50:50 ratio of THC and CBD and is usually given to patients with multiple sclerosis. There is anecdotal evidence that suggests that smoking cannabis has better effects than Sativex.

Another example demonstrating the importance of controlling for specific ratios of THC and CBD stems from research on potential treatments for schizophrenia. The effects of potential cannabis-derived treatments have been shown to vary based on the THC:CBD ratio, highlighting the importance of its control.

While scientists can extract pure cannabinoids from cannabis plants, it’s an expensive and arguably arduous method that produces low yields. New approaches such as the yeast-based methods could offer more efficient ways of producing these medically relevant compounds.

The wider impact of sustainable cultivation

It may be a great breakthrough for Canadian cannabis-based companies to investigate such innovative, ecologically safe, and cost-effective methods, and would also allow the nation to set an example for the world with progressive legislation. It would be a great showcase of sustainable development and economics — a perfect way to lay down roots for a new industry that is bound to thrive in the coming years.

We are creating history with respect to cannabis legislation and distribution. With the nation-wide legalization of cannabis, along with Germany and New Zealand importing Canadian-grown cannabis, it becomes imperative to pay attention to current methods of growth, the sustainability of which should be equally considered for its ecological and financial costs.