`CRACK' NICOTINE HOOKS SMOKERS; Addiction levels shock.

Byline: SIMON HOUSTON

SOME cigarettes could be almost 40 times more addictive than others, research has revealed.

Scientists have analysed the amount of super-addictive "freebase" nicotine in different brands for the first time.

Freebase nicotine vaporises and passes rapidly through the lungs into the bloodstream in a way that is compared to crack cocaine.

Because it reaches the brain so quickly, it is thought to be more addictive than normal nicotine.

In the American research, brands were compared with a lab "reference" cigarette containing one per cent freebase nicotine.

They ranged from one per cent to 36 per cent for a speciality US brand called American Spirit, which is on sale in limited outlets in Britain.

The popular Marlboro brand, the only one of the cigarettes tested to figure in the British top 10 sellers, contained up to 9.6 per cent freebase.

Although production differs between Britain and the US, British cigarettes contain some additives which increase freebase levels, such as ammonia.

Professor James Pankow, of Oregon Health and Science University, who led the study, said: "Since a drug becomes more addictive when it is delivered to the brain more rapidly, freebase nicotine levels are at the heart of the controversy regarding the industry's use of additives."

Professor Jack Henningfield, of the John Hopkins University School of Medicine in Baltimore, Maryland, said: "Cigarettes deliver much higher levels of freebase nicotine than previously thought, thus helping to explain their enormous addictive potential."

Now major brands could be under pressure to state clearly the levels of addictiveness.

Only additives on a permitted list from the Department of Health are allowed in cigarettes made in Britain. By next year, under strict EU rules, tobacco companies will have to remove 400 additives such as ammonia.

A spokeswoman for the Tobacco Manufacturers' Association in the UK said: "Cigarettes manufactured here do abide by the permitted list and may be quite different from those in America."

BIG DRAW

Addictive top five in America, following research into `freebase' nicotine.

American Spirit 36%

Marlboro 9.6%

Gauloises Blondes 7.5%

Winston 6.2%

Camel 2.7%