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The dangerous ignorance of those
who say 'legalise pot'

Professor Heather Ashton,
Daily Mail, April 28 1998

There are literally millions of people of all ages and all classes in this country who have tried cannabis and claim to have had no ill effects.

Indeed, as the Government launches its drugs White Paper – a document that maintains the strict official ban on cannabis – it's probably fair to say that the weight of liberal opinion is in favour of its legalisation.

There are MPs who argue that its use is harmless. At countless dinner parties the law is derided. One serious broadsheet newspaper has campaigned openly for cannabis to be made legal.

Why not, so the argument goes, when the drug is not nearly as dangerous as heroin, nor as addictive as cocaine, nor as unpredictable in its consequences as LSD or Ecstasy?

Why not, when the anti-cannabis laws are flouted so openly, when half the students at universities have tried it and when the drug is said to pose fewer dangers than either alcohol or tobacco?

Well, there are good reasons why not. As someone who, since the Seventies, has studied the effects on the human brain of various drugs – including cannabis – it seems to me that the 'legalise pot' campaigners are jumping ahead of the evidence in a cause that owes more to fashion than to hard science.

During my research I have come into contact with many different types of cannabis user, from students who consume it on a casual basis to habitual users.

I must stress I am not speaking as an anti-cannabis campaigner; I'm an academic, not a pundit or a politician keen on promoting a particular policy.

But as the pressure grows to legalise cannabis, it seems to me increasingly important that the facts should be understood, particularly by those who argue that cannabis isn't really harmful, anyway. It is time we took a long, dispassionate view of the evidence.

Take the claim that cannabis isn't addictive. Research demonstrates that this simply isn't true. My own experience with student users shows that they can and do suffer severe withdrawal symptoms when they try to come off the drug.

Once I was unable to complete my study of one group of chronic cannabis smokers in a commune because they could not keep their appointments. They lost their academic edge, and their studies suffered badly. And, crucially, those who stopped smoking the drug exhibited no great improvement.

A study in the U.S. conducted about ten years ago, underlined the point. A group of regular cannabis users were given oral doses of the drug under strict laboratory conditions. Later, unknown to them, the drugs were replaced by a harmless placebo.

Without their regular genuine 'fixes', they ended up suffering tremors, stomach pains, nausea, headaches and a range of other unpleasant side-effects. One of the reasons is the way cannabis is absorbed by the body. It isn't like alcohol, which can be sweated out within 24 hours. The narcotic effects of a single joint last 48 hours.

But the various chemical residues in the drug find their way into the body fat, where they remain for as long as a month. And of course regular users keep on absorbing more and more.

Contrary to claims by the legalise pot campaign, it definitely effects the brain function. A Department of Transport study in the late Eighties confirmed that cannabis impairs the ability to drive. Another study showed that, after alcohol, cannabis is the most common drug involved in road deaths.

Research into airline pilots who have smoked one moderate dose of the drug not only found that it had a marked impact on performance, but that the impairment lasted up to 48 hours.

Just as disturbing was the finding that, after 24 hours, those pilots were unaware that their abilities were still affected, but they continued to make potentially disastrous mistakes when they were tested on a flight simulator.

Now all this may seem somewhat overstated to the people who smoked the odd joint back in the Sixties and Seventies without seeming to suffer any great harm. Indeed, the legalisation campaigners point to the experience of those years as evidence that the drug is relatively safe.

But I fear they are missing the crucial point. Over the years, the strength of the average cannabis joint has increased because of careful plant-breeding and hydroponic farming to produce more potent varieties, such as Silver Pearl and Skunkweed. The old reefer of the Sixties offered a relatively mild dose. A modern joint can be as much as 30 times stronger. And of course the very fact of that increase in strength adds to the chemical deposits in the body and stimulates the desire for another strong buzz.

Whether or not this leads on to experimentation with harder drugs may be open to debate. But I think there is an analogy with alcohol abuse. Most people like a drink, but relatively few go on to become alcoholics. It must be true, however, that the more drinkers there are, the more alcoholics there will be. I suspect the same pattern applies to cannabis. The more users there are, the more some will be tempted to try something stronger.

This, after all, is what is suggested by the experience in Holland, where cannabis has been legal for years. The use of hard drugs has risen noticeably.

It is interesting to note that the Dutch authorities have now reduced the amount of cannabis that can be sold for personal consumption. There is one other point that the legalisers tend to overlook: the risk of cancer.

It took decades before the carcinogenic effects of tobacco smoke were fully understood. How long will it be before it dawns on cannabis users that they risk very nasty cancers of the throat, tongue and mouth, not to mention emphysema and other chest troubles?

In fact, in some respects a joint can be more dangerous than a cigarette because it has no filter and a higher igniting temperature.

If any future government is tempted to lift the ban on cannabis, it will have to do so despite the evidence that it creates dependency, that it impairs the cognitive function of the brain and that it poses a risk of cancer.

The only argument that is left concerns the undoubted fact that the present law is so widely flouted as to be virtually unenforceable. But wouldn't the law be equally unenforceable if the ban were lifted? After all, since cannabis clearly has a deleterious long-term effect, many groups in society would be forbidden from using it, no matter how liberal the Government wanted to appear.

Could we ever contemplate pilots, bus drivers or surgeons using the drug? How could we ever police a law that allowed some people to use the drug but forbad others?

There has been plenty of emotion in the drugs debate, plenty of passion and commitment. Am I alone in wishing for a more considered approach? And for a climate in which science and rational analysis can take the place of tub-thumping zealotry?

from: Cannabis Poses Risks
Reuters, February 1, 2001

LONDON (Reuters) – Cannabis is not the harmless recreational drug many users think it is but a dangerous substance that can cause paranoia, psychosis and severe anxiety and panic, psychologists warned on Thursday.

A review of research into the drug that first appeared in China nearly 5,000 years ago shows it can impair perception, motor skills and reaction times but it also has medicinal qualities for a range of illnesses.

"Cannabis affects almost every body system. It combines many of the properties of alcohol, tranquillisers, opiates and hallucinogens," said Professor Heather Ashton, of the University of Newcastle upon Tyne.

Ashton reviewed studies on the recreational use of cannabis, its potency and impact on the body and brain. Her research, published in the British Journal of Psychiatry, shows it is still popular among young people.

Sixty percent of university students in Britain have tried the drug and 20 percent use it regularly. In a recent survey some users admitted to smoking up to 15 joints or more a day.

Although most people smoke cannabis occasionally for its euphoric feeling, regular use has more serious side effects including impairment in memory, attention and the ability to process complex information.

"Whether there is permanent cognitive impairment in heavy long-term users is not clear," Ashton added.

And contrary to common belief, chronic users can develop a tolerance and dependence on cannabis which can lead to withdrawal effects similar to those of alcohol and opiates, she added.

Using the drug also increases their risk of developing bronchitis and emphysema. Smoking three or four joints a day is the equivalent of about 20 cigarettes.

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