We Fact Checked the Canadian Government’s Scary Weed Warnings

You won’t be able to miss the Canadian government’s glaring, yellow health risk warnings that will be slapped onto every gram of legal weed sold in this country come legalization.

According to a set of proposed rules released by Health Canada Monday, the government wants licensed weed producers to sell weed in plain coloured packaging (the example they used was white), with a red stop sign graphic that indicates the product contains THC, and a separate yellow health warning.

The warnings the government has proposed for weed sound pretty dramatic. (Especially when you consider that alcohol, a substance with far graver health effects, doesn’t come with these types of warnings.)

In a media briefing Monday, Eric Costen, Director General of the federal government’s Cannabis Legalization and Regulation Secretariat, said the messaging is based on “an exhaustive review of all the available scientific research on cannabis.”

Nonetheless, VICE reached out to experts to fact check the proposed warnings.

WARNING: Cannabis smoke is harmful. Harmful chemicals found in tobacco smoke are also found in cannabis smoke.

It’s true that smoking weed will have negative health impacts, David Hammond, a professor at the University of Waterloo’s school of public health, told VICE. “People don’t realize if you light any organic material on fire, it will produce thousands of chemicals. Most of the chemicals that cause cancer are just from smoke,” he said. He recommended people vape cannabis instead of smoking it.

However, Jenna Valleriani, a PhD student at the University of Toronto who researches cannabis, said there are far more studies on tobacco smoke than weed smoke so it’s hard to definitively say the latter is just as harmful as the former. The reason for this is cannabis is illegal so there haven’t been a ton of clinical trials on it.

According to the American Lung Association, smoking weed heavily can damage the lungs and lead to conditions like chronic bronchitis.

In an interview with Health, Steven Hoffman, a scientific director for the Canadian Institutes of Health Research, pointed out that we don’t know “whether or not cannabis itself causes or possibly even prevents cancer from developing.”

Verdict: It’s complicated

WARNING: Do not use if pregnant or breastfeeding. Using cannabis during pregnancy may harm your baby and result in low birth weight. Substances found in cannabis are also found in the breast milk of mothers who use cannabis.

Once again, there’s limited research on this subject, however the Canadian Centre on Substance Abuse says cannabis is the most popular "illicit drug" used during pregnancy and that prenatal exposure has been linked to adverse effects on cognitive development as well as premature birth and low birth weights.

A 2012 Pediatric Research article found that babies who had mothers that smoked cannabis during pregnancy were born 375 grams lighter than babies born to non-smoking moms.

Hammond told VICE that, as with nicotine or alcohol, mothers will pass on substances they ingest to their babies, both before they are born and during nursing. “Exactly how harmful it is, that’s really tricky,” said Hammond, because of the lack of clinical trials and women’s reluctance to admit they they have consumed an illicit drug while pregnant.

A Jamaican study that tracked babies born to mothers who used cannabis found that there was no significant difference in developmental outcomes of those babies and babies born to non-users, except that the cannabis babies scored higher on reflex tests at 30 days old. However the research is old, dating back to the early 90s.

Verdict: Accurate

WARNING: Do not drive or operate machinery after using cannabis. More than 4,000 Canadians were injured and 75 died from driving after using cannabis (in 2012). After cannabis use, coordination, reaction time and ability to judge distances are impaired.

Both the feds and the provinces are going after stoned driving hard, introducing tougher penalties and in some cases implementing a “zero tolerance” rule for drivers with THC in their systems.

Health Canada’s numbers are likely coming from this study. Valleriani pointed out the study is based on crude estimates, not actual crashes.

“The whole difficulty of detecting impairment would likely mean it'd be difficult to attribute deaths to impaired driving unless someone outright admitted to impairment.”

Once again, again research is limited and headlines on this issue in US states like Colorado, where weed is legal, are conflicting. The Centers for Disease Control and Prevention says while weed does negatively impact skills needed for driving, “it is unclear whether marijuana use actually increases the risk of car crashes.” Other studies suggest that drinking is still much more dangerous for driving than weed.

Verdict: Accurate but with qualifiers

WARNING: Cannabis can be addictive. Up to half of people who use cannabis on a daily basis have work, social or health problems from using cannabis. One in 11 people who use cannabis will become addicted. Up to 1 in 2 people who use cannabis daily will become addicted.

The debate over whether or not cannabis is addictive is highly contentious. But Hammond said while weed is less addictive than most other illicit drugs, “it’s not quite as benign as some folks will make out.” It comes down to the definition of addiction.

“Dependence used to be based on physiological withdrawal symptoms and stuff like that,” he explained, but “the classic definition of addiction is failure to control use and there’s some harm associated with that use.” In other words, if heavy cannabis ingestion is impacting your job, social life, or relationships, you may have problematic use.

Hammond told VICE he thinks the government has done a good job with trying to be nuanced in this warning, by being clear that it’s not recreational users who are likely to end up “addicted” to weed.

Verdict: It’s complicated

WARNING: Regular use of cannabis can increase the risk of psychosis and schizophrenia. Higher THC content can increase the risk of psychosis and schizophrenia. Higher THC content can lower the age of onset of schizophrenia. Young people are especially at risk.

Valleriani said although studies have found links between cannabis use and the early onset of schizophrenia (which is a type of psychosis), the strength of that relationship is still hazy.

“One could argue early initiation of cannabis use leads to an increased risk of early onset, especially for those with a pre-existing vulnerability and those who use cannabis daily,” she said, “but also third variables—like socio-demographic factors or using other drugs including alcohol and tobacco—make it more difficult for a clear picture.”

She also pointed out that many people report using cannabis to alleviate mental health issues, including depression and anxiety.

Hammond said the warning is important—especially in the case of products with higher THC content—because it may give pause to a person with a family history of schizophrenia.

Verdict: It’s complicated

WARNING: Adolescents are at greater risk of harms from cannabis. Early and regular use increases the risk of psychosis and schizophrenia. Using cannabis as a teenager can increase your risk of becoming addicted. One in 6 people who start using cannabis in adolescence will become addicted.

These warnings echo some of the other ones; the stat about teens having a greater risk of becoming addicted to weed comes from the US government’s National Institute on Drug Abuse. Hammond said the bottom line here is “you don’t want any young person using any drug frequently because their brain is still developing.”

Verdict: Accurate

Hammond said the goal of the warning labels should be harm reduction. He said it’s hard to get a message about a complicated issue like addiction down to one or two sentences, but “what these things do, if they’re effective, is get people talking.” Valleriana was a bit more critical. “While I see the need to be preventative, and I think warning labels are important, they are misleading,” she said. While it seems like the government may be fear-mongering to a certain degree, the question that really boggles the mind is why they’re being so hard on weed and yet alcohol requires almost no warnings.

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