Cannabis plants in BlissCo, a manufacturing facility in Langley, B.C. (Ashley Wadhwani/Black Press Media)

Here’s a first look at Canada’s sewage tests for cannabis use

The first-of-its-kind tests involve gauging traces of THC, the active ingredient in marijuana, at 15 wastewater treatment plants in Canada

Canadians eat or smoke anywhere between 400 to 1,600 tonnes of cannabis per year, according to a few months of sewage samples examined for the federal government.

The wide-ranging estimate, released by Statistics Canada on Thursday, is the first look at cannabis use through a new technique called wastewater-based epidemiology. The tests involve gauging traces of THC, the active ingredient in marijuana, at 15 wastewater treatment plants in five different cities, including Vancouver.

After cannabis is metabolized in the body, traces of THC are left behind in human waste. Scientists collected wastewater on the second week of each month from March to August this year – before cannabis was legalized in Canada on Oct. 17.

As expected, more cannabis is consumed in Canada’s larger cities. Montreal had the highest rate of consumption at roughly 1,922 grams per week, according to the analysis. Toronto had the second highest at 1,257 grams, followed by Vancouver with 721 grams.

READ MORE: Canadian trial to compare cannabis and fentanyl in relieving chronic pain

READ MORE: B.C. woman looks to reduce stigma surrounding weed-smoking moms

The sample tests were meant to overcome under-reporting by cannabis users, often caused by the stigma of the drug and reluctance for people to admit their illegal purchases.

“One consequence of under-reporting is that the size of the black market for cannabis will be similarly underestimated,” the report reads.

“As a result, without a direct measurement of cannabis consumption, the reduction of the black market for cannabis – one of the objectives of the legalization of non-medical cannabis – will be hard to track.”

READ MORE: 10 things still illegal in the new age of recreational cannabis

While the estimates offer a first look at the truth behind cannabis use, Statistics Canada said the numbers are experimental and that more information is needed, such as how much of the drug is excreted, its potency and the way the drug is consumed. Other factors to consider include different chemicals in the various treatment plants themselves.

“In the case of cannabis, there are many different kinds of products, with different THC potency levels, and this adds further complexity to estimation methods,” the report reads.

Sampling will continue until the spring of 2019.

WATCH: Inside a B.C.-based marijuana production facility


@ashwadhwani
ashley.wadhwani@bpdigital.ca

Like us on Facebook and follow us on Twitter.

Just Posted

Price for one-bedroom rentals in Kelowna jumped by 10.8 percent between October and November: Report

Out of 34 Canadian cities, report said Kelowna had highest monthly rent increase

Province covers medical costs for Kelowna boy with spinal muscular atrophy

Spinal taps for Rumi Green’s spinal muscular atrophy treatment cost $120,000 each

Warriors look to snap 4 game losing streak in Trail

West Kelowna takes on the Smoke Eaters Friday night

Funding sought for family of 15-year-old Summerland girl with cancer

Treatment will involve two weeks in hospital, followed by eight to 10 weeks recovery at home

Central Okanagan Journey Home Society names new executive director

Stephanie Ball will head the Journey Home strategy

VIDEO: More air-passenger rights go into effect this weekend

The first set of passenger rights arrived in mid-July in Canada

Best in business: North-Okanagan Shuswap companies named top 10 semi-finalists

Small businesses from Vernon, Kelowna, West Kelowna, Salmon Arm to compete for top spot

Sagmoen’s lawyer argues ‘abuse of power’ in police search

The trial of Curtis Sagmoen continued at the Vernon Law Courts on Friday

Swoop airlines adds three destinations in 2020 – Victoria, Kamloops, San Diego

Low-fair subsidiary of WestJet Airlines brings new destinations in April 2020

Aid a priority for idled Vancouver Island loggers, John Horgan says

Steelworkers, Western Forest Products returning to mediation

Navigating ‘fever phobia’: B.C. doctor gives tips on when a sick kid should get to the ER

Any temperature above 38 C is considered a fever, but not all cases warrant a trip to the hospital

Penticton resident allegedly has rear car tires stolen

The resident woke up today to find their back tires missing and their car on blocks

Woman struck, dog killed after collision on Highway 97

Speed is not believed to be a factor and alcohol has been ruled out

Province covers medical costs for Kelowna boy with spinal muscular atrophy

Spinal taps for Rumi Green’s spinal muscular atrophy treatment cost $120,000 each

Most Read