Might I suggest if someone wants a recent, up to date and thorough but easy to understabd discussion about marijhuana use they go to:
https://www.drugabuse.gov/publications/marijuana/All my info comes from the above and it also backs up the article Godess presented with some more references.
As you may already know the main psychoactive (mind-altering) chemical in marijuana, is delta-9-tetrahydrocannabinol commonly referred to as THC. THC is known to remain in the body for days or even weeks after use and the immediately noticeable effects of smoking marijuana generally last from 1 to 3 hours, but if eaten longer.
What there is no doubt about is that marijuana significantly impairs judgment, motor coordination, and reaction time, and studies have proven a direct relationship between blood THC concentration and impaired driving ability. No one debates that.
This is why the proposed law on recreational use suggests a $1,000 fine for any level of THC in the blood stream of a driver and this is a precursor to drivers saying the law is not fair, the THC consumed was days earlier.
Let's be crystal clear. There is no acceptable limit of marijhuana. You can't draw a line and say under a certain level of blood concentration it won't impair driving ability.
With that in mind it should be no surprise Marijuana is the the substance most frequently found in the blood of drivers who have been involved in vehicle crashes, including fatal ones.
Like I said marijhuana can be detected in body fluids for days or even weeks after intoxication and because people frequently combine it with alcohol or other drugs and so without a zero tolerance policy to any level of THC confusion would be rampant in criminal or provincial highway and traffic enforcement legislation for impaired driving.
What studies have shown is that those involved in vehicle crashes with THC in their blood are three to seven times more likely to be responsible for the incident than drivers who had not used drugs or alcohol. So needless to say the risk associated with marijuana in combination with alcohol appears to be greater than that for either drug by itself.
Studies on the increase of risk of car accidents with marijhuana clearly indicate a sizeable increase in risk but since people using smoke dope and drink together its hard to be distinctively clear between the two.
What worries me is marijuana potency has steadily increased over the past few decades
For example in the early 1990s, the average THC content in confiscated marijuana samples was roughly 3.7 percent. In 2014, it was 6.1 percent.
Also keep in mind newer improsed methods of smoking or eating THC-rich hash oil extracted from the marijuana plant (dabbing) delivers very high levels of THC to the person. For example, the average marijuana extract contains more than 50 percent THC, with some samples exceeding 80 percent.
Add to that the fact that researchers in psychology, neurology, psychiatry and pharmacology do not know the full extent of the consequences when the body and brain (especially the developing brain) are exposed to high concentrations of THC.
As well delta-9-tetrahydrocannabinol (THC) is one of more than 500 other chemicals, including more than 100 compounds that are chemically related to THC, called cannabinoids and they also have not been definitively studied.
What does exist from animal research and a number of studies in humans appears to indicate that marijuana exposure during development CAN cause long-term or possibly permanent adverse changes in the brain.
For example, rats exposed to THC before birth, soon after birth, or during adolescence show notable problems with specific learning and memory tasks later in life. Cognitive impairments in adult rats exposed to THC during adolescence are associated with structural and functional changes in the hippocampus Studies in rats also show that adolescent exposure to THC is associated with an altered reward system, increasing the likelihood that an animal will self-administer other drugs (e.g., heroin) when given an opportunity.
Everything I state above comes out of the series of articles I quoted if you want the references to the studies.
My words above repeat and summarize the article for discussion purpose but do not come from me direcly.
That said I obviously read them and other studies very much like them that say the same things.
I am concerned that legalization of marijhuana for people with cancer, glaucoma, epilepsy, arthritis, lupus, chronic pain diseases where medication makes things worse makes sense. My friend gave me an edible marijhuana for my foot because I have arthritis from years of running and it took the pain away entirely and the only slight effect was a very mild buzz but I would have never driven in that state.
That said, I might consider it for arthritis if it gets really bad. Right now most times I can ignore it. Also because I am allergic to narcotics the studies I read from medical doctors suggests it will be a more prominently used pain killer as an option to opiates in years to come and they are working on edible forms and nasal spray delivery.
The edible candy my friend made I could handle. I do not smoke today's dope because I find it causes nothing but paranoia and anxiety. It could be its more potent than in my day (I am 61) or I am an old fart who doesn't break it down like I used to but for me its not a recreational option but I am a strong supporter of it being used by chronic or terminal pain patients or people with specific diseases.
In terms of legalizing it, I don't think it should be illegal but myself I favour it sold by the liquor boards of each province not private individuals. I am a huge supporter of the liquor board and its enforcing and monitor of drinking.
I also have very very serious concerns our car accident rates in terms of fatal and non fatal accidents are going to sky rocket when marijhuana is legalized. No doubt the feds and provs will get fat on taxes and driving fines but its not going to prevent huge increases in risks associated with driving. Look at how difficult it is educating people about drinking, now we have to add dope education.
My worries are with car accidents. My worries are also that since we don't know the long term impact on thc and other chemicals on the brain absolutely what we are seeing now in studies are early signs of long term brain damage associated with neurotransmission and memory.
Also marijhuana when added to bipolar disorder, schizophrenia, schoizophreniform, certain delusional and mood disorders, can trigger uncontrollable anxiety, psychosis, suicide, violence.
There are long term users who can get BOTH physically and psychologically addicted and some psychologically but not physically addicted.
There is also no pretending that smoking dope increases lung and heart associated diseases as well as being dangerous with blood circulation and so dangerous for diabetics, hemophiliacs, people on blood thinners, people on high blood pressure medication.
Heavy use of marijhuana is now being linked to higher rates of testicular cancer and men growing breasts.
All nice to keep in mind.
I worry with teenagers. They have a difficult enough time as their brains change from the size of a pin to a watermelon size in the front lobe which can be impacted by marijhuana use. Since many mental illnesses that can be triggered and made worse by marijhuana like bi-polar disorder, depression, general anxiety disorder and schizophrenia only show initial or early symptoms during puberty, it may be even more difficult to diagnose them as they will add to the confusion as to whether the unstable or unusual behaviour is simply puberty and/or marijhuana or the other illnesses as well.
I also think the combo of a teenager with booze and dope, or booze or dope and a car is worrisome.
What I am uncomfortable with as well is how certain special interest groups used insider connections with Trudeau to set themselves up as a monopoly once legalization transpires to control the sale of dope.
I think its unrealistic to think marijhuana sales outside government controlled marijhuana sales will go away.