The Rt Hon The Lord Tebbit.
The House of Lords
London
SW1 1AA

REF: The strength of cannabis today compared to the past half century

Lord Tebbit,

When you were being interviewed by Sky News on Saturday 10th February, over the matter of David Cameron’s possible use of cannabis as a 15-year-old pupil at Eton, you mentioned that cannabis today is many times stronger now than in those days.

Whereas it is true that today’s home-produced indoor and hydroponics cannabis is often stronger than home-produced – mostly garden or greenhouse – cannabis twenty or thirty years ago, that is a result of changes in growing techniques and the added need to secrecy resulting from a greater threat of prosecution for cultivation nowadays. But it’s also true that much of the cannabis available now is weaker than some of the cannabis imported in those days.

On the other hand much of the cannabis resin on the streets of the UK today is not only considerably weaker, but contains unknown and possibly dangerous adulterants and contaminants added by unscrupulous criminal suppliers – which would be protected against in a regime where cannabis was legal.

The experts in the IDMU, The Independent Drug Monitoring Unit have studied claims that cannabis strength has increased over the years and this is what they say:

While the potency of herbal cannabis may have increased, this is because high quality material is more readily available (i.e. grown in the UK from 'pedigree' seeds as sinsemilla), rather than seeded compressed material grown abroad and semi-decomposed before it reaches the consumer. High-quality herbal and resin has been seized by customs since the 1970s (See Gough TA Ed 1991 The Analysis of Drugs of Abuse). The potency of resin, if anything, would appear to have declined in recent years. The FSS quotes resin potencies between 3 and 7%, the range I have encountered is from 0.5% ('Formula') to 12% (Nepalese/Minali), with 'soap bar' typically around 4-6%. Resin typically contains significant quantities of CBD as well as THC, whereas herbal contains little if any CBD.

So although your claim has an element of truth in it, it is mis-information promulgated by those who support cannabis prohibition – notably people who don’t use it!

Yours faithfully,

Alun Buffry

21 February 2007

Thanks you for your letter of 11 February.

I do not accept what you say, nor the conclusion you reach.

Yours sincerely

Tebbit
House of Lords

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