The Canadian government has spent the past year testing for drugs all the waste flushed down the toilet in major Canadian cities — and the results are in.
As part of a yearlong pilot project, Statistics Canada has been collecting wastewater samples coast to coast from Halifax, Nova Scotia; Montreal; Toronto; Edmonton, Alberta; and Vancouver, British Columbia; to better understand cannabis and drug use of the 8.4 million residents living in these sample areas. That's roughly 20% of the population.
Montreal and Halifax were found to possess the highest levels of cannabis use by a wide margin. The levels were determined by testing for THC-COOH, the byproduct created by the body after consuming cannabis containing THC. Cannabis consumption was estimated at 84 tons across all of the test sites during the 12-month period.
“Montreal and Halifax reported loads 2.5 to 3.8 times higher than Vancouver, Toronto, and Edmonton,” Statistics Canada wrote in the summary of findings. “The average load of THC-COOH found in the wastewater for all sites combined was 450 grams per million people per week, but there were significant differences across the cities.”
According to the census agency, the study helps to understand widespread drug use within Canada's major urban centers. This picture also will allow the agency to understand societal drug use relating to specific substances while giving another metric to understand the size of the underground drug market.
The study also tested for other drugs using chemical markers left in the waste. Finding that there were higher instances of methamphetamine in Vancouver and Edmonton, it also was noted that levels of the same drug were “extremely low” in samples tested from Halifax.
The report also notes that there were spikes of THC-COOH in May, June, and December 2018. Statistics Canada said it is uncertain whether the spikes are due to variations in wastewater flow rates, short-term changes in the number of people consuming, the amount consumed, or factors related to the sampling. Finding precision estimates are a difficult task with this type of testing, especially when it comes to cannabis.
“The precision of the estimate is affected by uncertainty in the percentage of THC-COOH excreted in urine and feces after consuming cannabis,” the study said.
“Further research to refine the excretion rate of THC and some other drugs is required to improve the quality of wastewater-based estimates of drug use.”
Statistics Canada also noted that the estimates produced for cocaine and methamphetamine are significantly more precise than those for cannabis. Due to the illegal status of those substances, consumption is expected to be underreported. Ultimately, the total consumption was estimated at 370 kilograms, or 816 pounds, for cocaine and at 310 kilograms, or 683 pounds, for methamphetamine across the test sites.
The completion of the study marked what the census agency called the “first large-scale wastewater-based estimates of cannabis, methamphetamine, and cocaine consumption in Canada.”
Feature image: Canada has a novel way of determining how much marijuana Canadians consume: by testing sewage. Statistics Canada, the nation's census bureau, collected wastewater samples to examine for the presence of marijuana, as well as for cocaine and methamphetamine. (Gina Coleman/Weedmaps)
This article was republished from Daily Hive under a content-sharing agreement. Read the original article here.