The Big Question:

WHAT IS THE TRUTH ABOUT SKUNK, AND HAVE THE DANGERS BEEN OVERSTATED?

Why are we asking this now? Yesterday, the Advisory Council on the
Misuse of Drugs began reviewing scientific evidence on the
classification of cannabis, amid widespread fears that Britain is in
the grip of an epidemic of cannabis-induced psychosis. This view is
based on the belief that cannabis sold on the streets is stronger
than it was a generation ago and is tipping vulnerable people into
mental illness, including schizophrenia.

The review, the second in two years, was ordered by Gordon Brown, who
has indicated he is minded to reverse the decision of the former Home
Secretary David Blunkett, who downgraded the drug from Class B to
Class C in 2004. Mr Blunkett's aim was to free up police time
squandered on prosecuting users, but the Prime Minister is concerned
that the move sent the wrong message to young people, who are now
confused about drug laws.

What is skunk?

It is the generic name given to potent strains of the cannabis plant
containing the highest levels of the psychoactive ingredient
tetrahydrocannabinol (THC). The original skunk, a cross between the
fast-growing Indica and the potent Sativa strains, is believed to
have originated in the US and was so called because of its pungent
smell. Dutch growers have since refined and cross-bred the plants to
produce a number of strains including super-skunk, Early Girl,
Northern Lights and Jack Herer. They are normally grown indoors under
lights, or in a greenhouse. The more intensive the cultivation, the
higher the THC content.

How strong is skunk?

Traditional herbal cannabis contains 2 to 4 per cent THC, according
to the Drugscope charity. More potent varieties average 10 to 14 per
cent - three to four times as strong. Claims that skunk is 20 to 30
times as powerful as herbal cannabis are exaggerated. A European
review of cannabis potency in June 2004 concluded that the overall
potency of cannabis products on the market had not increased
significantly because imported cannabis dominated the market in most
countries. However, as home-grown cannabis has become more widely
available, especially in the Netherlands and Britain, consumption of
stronger varieties has increased. The Home Office yesterday claimed
that 70 per cent of cannabis sold on the streets of Britain was skunk.

Why is skunk so popular?

It offers a powerful high, similar for some users to that obtained
with ecstasy or LSD but without the chemicals. Even in the world of
recreational drugs, users prefer a "natural" high. It can be
home-grown from legally obtainable seeds - many users grow a few
plants on a windowsill for personal consumption. It is easy to
identify, making it difficult to fake. Cannabis resin, by contrast,
has been adulterated with everything from boot polish to the horse
tranquilliser ketamine.

How dangerous is skunk?

This is an area of intense dispute. The greatest concern is over its
effects on mental health. When the advisory council last reviewed
cannabis in early 2006, it concluded that use of the drug by existing
schizophrenia sufferers might worsen their symptoms and lead to a
relapse in some. But on causation, it said: "The evidence suggests,
at worst, that using cannabis increases the lifetime risk of
developing schizophrenia by 1 per cent."

Some scientists believe this underplays the risks. Professor Robin
Murray, of the Institute of Psychiatry in London, says that in
vulnerable individuals - those with an unsuspected genetic
predisposition to schizophrenia - cannabis may be the trigger that
starts a full-blown mental illness.

His research showed that up to 10 per cent of the adult population -
or about four million people - are prone to paranoid thoughts or
grandiose ideas and, among those who smoke cannabis regularly, half
may be tipped into psychotic delusions and end up needing treatment.
The early age at which people start smoking the drug today, compared
with two or three decades ago, is an additional concern, he says,
because their brains may be more vulnerable.

Have the risks been overstated?

Yes. A recent report, printed in several newspapers last month,
suggested that 500 people a week were being admitted to hospital for
treatment for the effects of cannabis - a 50 per cent increase since
the drug was downgraded to Class C in 2004. The figure was repeated
in reports this week. Drugscope said the figure, quoted by the Public
Health minister Dawn Primarolo, was actually related to the number of
people consulting community drug treatment services for help or
advice where "treatment" may amount to no more than an informal chat.
The actual figure for hospital admissions was 14 per week in 2006-07
- - and that was lower than the year before.

So why did the advisory council recommend that cannabis remains a Class C drug?

Because, despite the evidence of a link with schizophrenia, it
concluded that cannabis remained "substantially" less harmful than
the Class B drugs amphetamines and barbiturates. The classification
of drugs is, in part, about proportionality. Experts have long argued
that the current system for ranking drugs - Class A for the most
dangerous to Class C for the least dangerous - is irrational. In
terms of harm caused, alcohol and tobacco are more dangerous than
cannabis, yet they are legal and cannabis is illegal. Defenders of
the 2004 decision to downgrade cannabis to Class C say that it has
not increased its use and it has freed police to tackle drug-dealers
and other more serious crimes. Since 2004, consumption of cannabis
has actually declined.

Are there other risks from skunk?

Yes - but they are small. Skunk is smoked like cannabis, contains
carcinogenic substances and is often mixed with tobacco. The British
Lung Foundation estimated that smoking three joints was equivalent to
smoking 20 cigarettes but most users give up after a few years. Some
experts also believe there is a risk of dependence among regular
smokers. However, cannabis is not seen as a drug of addiction like
heroin or tobacco.

The greatest fear, alongside its effect on mental health, is that
skunk may lead people on to use harder drugs. It is certainly true
that many people who become heroin addicts have used cannabis in the
past. But the vast majority of cannabis users never progress to
heroin. Research by the Home Office concluded that the so-called
"gateway effect" of cannabis - leading users on to harder drugs - was
probably "very small".

Should the newer, more potent forms of cannabis be re-classified?

Yes...

* Vulnerable individuals with a predisposition to mental illness may
be tipped into psychosis by the drug

* The younger age at which people start smoking means their brains
are more vulnerable

* Skunk cannabis is three to four times stronger than herbal cannabis
and has more potent effects

No...

* At worst, the experts say, the use of cannabis increases the
lifetime risk of schizophrenia by only 1 per cent

* The chances that users of skunk will progress to harder drugs such
as heroin are very small

* Skunk is safer than alcohol and tobacco, which are legal and cause
more than 100,000 deaths a year