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

Suggested Topics
PROMOTED VIDEO
Life and Style
ebookA wonderful selection of salads, starters and mains featuring venison, grouse and other game
News
video
Life and Style
tech
Arts and Entertainment
Southern charm: Nicolas Cage and Tye Sheridan in ‘Joe’
filmReview: Actor delivers astonishing performance in low budget drama
Arts and Entertainment
While many films were released, few managed to match the success of James Bond blockbuster 'Skyfall'
film
Arts and Entertainment
Up my street: The residents of the elegant Moray Place in Edinburgh's Georgian New Town
tvBBC's The Secret History of Our Streets reveals a fascinating window into Britain's past
Extras
indybest
News
Albus Dumbledore, the headmaster of Hogwarts School of Witchcraft and Wizardry has been the teaching profession's favourite teacher
education
Sport
Luis Suarez looks towards the crowd during the 2-1 victory over England
sport
Life and Style
Cheesecake frozen yoghurt by Constance and Mathilde Lorenzi
food + drinkThink outside the cool box for this summer’s frozen treats
News
John Barrowman kisses his male “bride” at a mock Gretna Green during the Commonwealth Games opening ceremony
peopleBarrowman's opening ceremony message to Commonwealth countries where he would be sent to prison for being gay
Sport
Sir Bradley Wiggins removes his silver medal after the podium ceremony for the men’s 4,000m team pursuit in Glasgow yesterday
Commonwealth games Disappointment for Sir Bradley in team pursuit final as England are forced to settle for silver
Sport
Alistair Brownlee (right) celebrates with his gold medal after winning the men’s triathlon alongside brother Jonny (left), who got silver
England's Jodie Stimpson won the women’s triathlon in the morning
Independent
Travel Shop
the manor
Up to 70% off luxury travel
on city breaks Find out more
santorini
Up to 70% off luxury travel
on chic beach resorts Find out more
sardina foodie
Up to 70% off luxury travel
on country retreats Find out more
Latest stories from i100
Have you tried new the Independent Digital Edition apps?

ES Rentals

    Independent Dating
    and  

    By clicking 'Search' you
    are agreeing to our
    Terms of Use.

    iJobs Job Widget
    iJobs General

    SQL Report Analyst (SSRS, CA, SQL 2012)

    £30000 - £38500 Per Annum + 25 days holiday, pension, subsidised restaurant: C...

    Application Support Analyst (SQL, Incident Management, SLAs)

    £34000 - £37000 Per Annum + excellent benefits: Clearwater People Solutions Lt...

    Embedded Software / Firmware Engineer

    £40000 - £45000 per annum + Pension, Holiday, Flexi-time: Progressive Recruitm...

    Developer - WinForms, C#

    £280 - £320 per day: Progressive Recruitment: C#, WinForms, Desktop Developmen...

    Day In a Page

    Backhanders, bribery and abuses of power have soared in China as economy surges

    Bribery and abuses of power soar in China

    The bribery is fuelled by the surge in China's economy but the rules of corruption are subtle and unspoken, finds Evan Osnos, as he learns the dark arts from a master
    Commonwealth Games 2014: Highland terriers stole the show at the opening ceremony

    Highland terriers steal the show at opening ceremony

    Gillian Orr explores why a dog loved by film stars and presidents is finally having its day
    German art world rocked as artists use renowned fat sculpture to distil schnapps

    Brewing the fat from artwork angers widow of sculptor

    Part of Joseph Beuys' 1982 sculpture 'Fettecke' used to distil schnapps
    BBC's The Secret History of Our Streets reveals a fascinating window into Britain's past

    BBC takes viewers back down memory lane

    The Secret History of Our Streets, which returns with three films looking at Scottish streets, is the inverse of Benefits Street - delivering warmth instead of cynicism
    Joe, film review: Nicolas Cage delivers an astonishing performance in low budget drama

    Nicolas Cage shines in low-budget drama Joe

    Cage plays an ex-con in David Gordon Green's independent drama, which has been adapted from a novel by Larry Brown
    How to make your own gourmet ice lollies, granitas, slushy cocktails and frozen yoghurt

    Make your own ice lollies and frozen yoghurt

    Think outside the cool box for this summer's tempting frozen treats
    Ford Fiesta is UK's most popular car of all-time, with sales topping 4.1 million since 1976

    Fiesta is UK's most popular car of all-time

    Sales have topped 4.1 million since 1976. To celebrate this milestone, four Independent writers recall their Fiestas with pride
    10 best reed diffusers

    Heaven scent: 10 best reed diffusers

    Keep your rooms smelling summery and fresh with one of these subtle but distinctive home fragrances that’ll last you months
    Commonwealth Games 2014: Female boxers set to compete for first time

    Female boxers set to compete at Commonwealth Games for first time

    There’s no favourites and with no headguards anything could happen
    Five things we’ve learned so far about Manchester United under Louis van Gaal

    Five things we’ve learned so far about United under Van Gaal

    It’s impossible to avoid the impression that the Dutch manager is playing to the gallery a little
    Screwing your way to the top? Good for Lana Del Rey for helping kill that myth

    Screwing your way to the top?

    Good for Lana Del Rey for helping kill that myth, says Grace Dent
    Will the young Britons fighting in Syria be allowed to return home and resume their lives?

    Will Britons fighting in Syria be able to resume their lives?

    Tony Blair's Terrorism Act 2006 has made it an offence to take part in military action abroad with a "political, ideological, religious or racial motive"
    Beyoncé poses as Rosie the Riveter, the wartime poster girl who became a feminist pin-up

    Beyoncé poses as Rosie the Riveter

    The wartime poster girl became the ultimate American symbol of female empowerment
    The quest to find the perfect pair of earphones: Are custom, 3D printed earbuds the solution?

    The quest to find the perfect pair of earphones

    Earphones don't fit properly, offer mediocre audio quality and can even be painful. So the quest to design the perfect pair is music to Seth Stevenson's ears
    US Army's shooting star: Lt-Col Steven Cole is the man Hollywood calls when it wants to borrow a tank or check a military uniform

    Meet the US Army's shooting star

    Lt-Col Steven Cole is the man Hollywood calls when it wants to borrow a tank or check a military uniform