Cannabis is Cannabis


Cannabis is also known as: marijuana, kush, pot, weed, Mary Jane/MJ, grass, ganja. Cannabis is used today for medicinal and/or non-medical purposes. Non-medical use of cannabis was legalized on October 17, 2018 in Canada. It comes in the form of dried plant buds, hashish (dried resin from plant leaves) or oil (boiled resin). There are many ways that cannabis can be consumed, including: 

  • Inhalation (smoking, such as a “joint”; in a pipe or bong; vaping)
  • Ingestion (in the form of an edible or drink)
  • Topical (applied and absorbed through the skin using an oil)
  • Oral-Mucosal (applied under tongue or sprayed into mouth)


Cannabis Legalization

Prior to cannabis legalization, the Community Drug and Alcohol Strategy – including the Grey Bruce Health Unit and several other partners – held community information sessions about cannabis. Much of the information presented then remains relevant today. Slides from these presentations are found below:

“Weeding Out the Myths” - Parents: Help your teen understand what’s fact and fiction about cannabis

Non-Medical Cannabis

Interested in planning your own information sessions about cannabis? Use the Cannabis Toolkit Brochure


What are the Health Effects of Cannabis Use?

The extent of risks and harms of cannabis use are not entirely clear but the research shows that cannabis is not harmless. There are chemicals in cannabis which can cause cancer, damage your lungs, and affect the brain. When smoked, chemicals such a carbon monoxide, cyanide, benzopyrene, and tar are produced. Additionally, illegally sourced cannabis may contain pesticides, other drugs, heavy metals, moulds or fungi, or other unknown substances.

Delta-9-tetrahydrocannabionl (THC) is the component contained by the cannabis plant, which causes the ‘high’ experienced by users. This varies depending on:

  • The part of the plant that is used;
  • How the plant is bred;
  • How the product is processed.

In some cases, cannabis may be laced with other drugs such as fentanyl, cocaine or tobacco.

Higher potency of THC can result in more harmful effects for those who use it. Cannabidiol (CBD) mediates the effect of THC on the endocannabinoid system and may help to manage pain. When consumed, cannabis causes short and long term health effects;

Short term effects:

  • Increased heart rate
  • Decreased attention span
  • Slowed reaction time
  • Lack of a sense of time
  • Nervousness or paranoia

Long term effects:

  • Physical and mental health problems
  • Decreased cognitive functioning (memory, attention, problem solving)
  • Impaired ability to drive a vehicle
  • Reproductive health issues
  • Increased risk of addiction
  • Lung health issues


Health Effects of Cannabis

Parents, Educators and Adult Allies

Youth and Young Adults

Adolescence is an important time for the developing brain since most brain development happens before the mid-20’s. The THC in cannabis disrupts the same biological system in the brain that guides brain development. This means that youth are particularly at risk of the negative consequences that can result from cannabis use.

Some people say they use cannabis to help them cope with stress or their mental health. If you find you are using cannabis for these reasons, check out how to deal with stress in a positive way.

Clarity on Cannabis | Rural Development Network (Virtual Exhibit for Grades 10 to 12)

Effects of Cannabis Use During Adolescence

Fact and Fiction about Marijuana

Talking Cannabis (

Home | WhatWithWeed (

Cannabis: Important things to know - Kids Help Phone

Cannabis & Psychosis – Exploring the Link (

University of Waterloo Cannabis Resources

Kids Helpline Phone: 1-800-668-6868 - 24 hours a day, seven days a week (Canada only)

ConnexOntario Helpline: 1-866-531-2600 or download ConnexGo on the App Store or Google Play

Pregnant and Breastfeeding Women

Just like with tobacco, a pregnant or lactating person’s use of cannabis can affect her fetus or newborn child, which can lead to health problems.  There is no known safe amount of cannabis use in pregnancy and when feeding breastmilk.  The toxins in cannabis are carried through blood to the fetus during pregnancy, as well as in the breast milk.

Heavy cannabis use during pregnancy can lead to lower birth weight of the baby. It has also been associated with longer-term developmental effects in children and adolescents, such as:

  • Decreased memory function
  • Lessened ability to pay attention
  • Decreased reasoning and problem-solving skills
  • Hyperactive behavior
  • Increased risk for future substance use


THC and other chemicals in cannabis will get into the breast milk and may affect the baby. The THC can move into the baby’s fat tissue, as well as into the brain. Cannabis is not recommended for anyone while pregnant or breastfeeding.




Best Start Resource Centre- Risks of Cannabis on Fertility, Pregnancy, Breastfeeding and Parenting

Thinking about using cannabis before or during pregnancy?

Cannabis, Pregnancy and Breastfeeding

Drug Impaired Driving

Cannabis use impairs the key functions required for driving safely, including:

  • cognition
  • attention
  • decision-making
  • motor skills and coordination
  • reaction time


Research has shown that cannabis-impaired driving doubles the risk of being involved in a motor vehicle accident, including fatal collisions. This risk even further increases when cannabis use is combined with alcohol. Impairment can last 3 to 6 hours after use. It is recommended that users do not drive (or operate machinery) for at least 6 hours after use of cannabis.

For young drivers, driving after using cannabis is more common than driving after drinking alcohol. Youth aged 18-19 are most likely to drive following cannabis consumption, followed by those aged 15-17 years old.

Drug Impared Driving

Source: Don’t Drive High. Your life can change in an instant: Fast facts about drug-impaired driving (DID) -



Clearing the Smoke on Cannabis: Cannabis Use and Driving – An Update | Canadian Centre on Substance Use and Addiction (

Harm Reduction and Cannabis Use

In order to reduce the potential negative health effects of cannabis, it is safest not to use.

However, if you choose to use cannabis:

  • Delay cannabis use (brain continues to develop into mid-20s)
  • Know what you’re using and choose lower-risk, less potent (lower THC), cannabis products
  • Don’t use synthetic, or man-made, versions of cannabis (e.g. K2 or Spice)
  • Avoid smoking cannabis – choose something safer like vaporizers or edibles
  • Avoid ‘deep inhalation’ or ‘breath-holding’
  • Limit and reduce how often you use cannabis
  • Don’t use cannabis and drive, or operate other machinery (wait at least 6 hours after using cannabis to drive)
  • Avoid combining risks listed above
  • Don’t use cannabis if you are at risk for mental health problems or are pregnant


Find more on how to lower your risk of harm:

CAMH - Lower Risk Cannabis Use Guidelines

Canadian Public Health Association - Cannabasics

Cannabis and the Workplace

It is illegal to use non-medical cannabis in the workplace, or to be under the influence of cannabis while at the workplace.

Below are a resource and toolkit that employers and employees can look to for information on addressing substance use in the workplace.

Cannabis Legalization

Bill C-45, known as the Cannabis Act, came into effect in October 2018. In 2018, the provincial government released its legislative framework outlining how they plan to manage the federal legalization in Ontario. Please note the following information pertains to recreational cannabis use, not cannabis that is prescribed for medical reasons.


Legal Age

No person under 19 years of age can possess or consume cannabis.


Where you can use Cannabis

The Cannabis Statute Law Amendment Act, 2018 (Bill 36) makes the smoking and vaping of cannabis (medical and non-medical use) subject to the same prohibitions as the smoking and vaping of tobacco products as set out in the Smoke-Free Ontario Act, 2017 (SFOA). Cannabis edibles are currently unregulated, but it is projected that they will be legalized at a later date.

Grey Bruce Health Unit is responsible for enforcing the Smoke-Free Ontario Act in our region. The revised SFOA has incorporated a new restriction making all community recreational facilities owned by the Province, municipalities, charities or non-profit organization smoke and vape-free.


Cannabis Sales

The Alcohol and Gaming Commission of Ontario (AGCO) will be responsible for granting and revoking licenses to sell cannabis.


Controlling Access

Adults who are 19 years old or older would be legally able to:

  • possess up to 30 grams of legal dried cannabis
  • share up to 30 grams of legal cannabis with other adults
  • purchase dried or fresh cannabis or cannabis oil from a licensed retailer
  • grow up to 4 cannabis plants per residence to a maximum height of 100 cm


Legalizing and Strictly Regulating Cannabis: The Facts

Prevalence of Use

Cannabis use prevalence rates are highest among youth and young adults (MLHU, 2016).

Results from the Ontario Student Drug Use and Health Survey (Boak, et al., 2015) represent 10,426 students from 220 schools in grades 7-12, and their cannabis use.

  • 21.3% of students report using cannabis at least once during the 12 months before the survey, representing about 203,900
  • Males (22.0%) and females (20.5%) are equally likely to use cannabis;
  • Use significantly increases with grade, to a high of 37.2% among 12th graders;
  • There are no significant regional differences.


Daily Cannabis Use

About 2.1% use cannabis on a daily basis, representing about 20,000 students. There is no significant difference between males (2.3%) and females (1.9%).


Cannabis Dependence (Grade 9-12)

About 2.2% report symptoms of cannabis dependence, representing about 14,900 high school students in Ontario.


Review the Ontario Student Drug Use and Health Survey for further information.



Boak, A., Hamilton, H. A., Adlaf, E. M., & Mann,R. E., (2015). Drug use among Ontario students,1977-2015: Detailed OSDUHS findings (CAMH Research Document Series No. 41). Toronto,ON: Centre for Addiction and Mental Health.

Middlesex-London Health Unit (2016). Cannabis: A Public Health Approach. London, Ontario: Author.


Cannabis Edibles, Extracts and Topicals

Start low, go slow

If you choose to consume cannabis, how much you consume and how quickly you consume can influence whether or not you experience adverse effects. Take your time to understand how your body reacts to cannabis as everyone’s response is different. Until then, start low and go slow to minimize health risks and the risks of overconsumption.

Start with a low amount of THC and wait to feel the effects before taking more.

Edible cannabis:

  • Look for products that contain 2.5 mg of THC or less
  • Effects felt within 30 minutes to 2 hours
  • It can take up to 4 hours to feel the full effects


Final Regulations: Edible Cannabis, Cannabis Extracts, Cannabis Topicals



  1. New cannabis products: What Canadians need to know - YouTube
  2. What You Need To Know If You Choose to Consume Cannabis
  3. Edible Cannabis: Implications for public health nutrition practice



Start Low, Go Slow | Government of Canada

Cannabis: What Parents/Guardians and Caregivers Need to Know

Cannabis: Inhaling vs Ingesting

Edible Cannabis, Cannabis  and Cannabis Topicals: A Primer on the New Cannabis Products

7 Things You Need to Know about Edible Cannabis

Always Read the Label | Canadian Centre on Substance Use and Addiction



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