Pubdate: Sat, 28 Oct 2000 Date: 10/28/2000 Source: Times, The (UK) Author: Mary Buck Sir, Were cannabis to be legalised/decriminalised, the strength of tetra-hydrocannabinol in each "cigarette" would presumably be controlled. This is the component in the plant which has an effect on the user. Its strength varies according to where the plant is grown; that is, the hotter the climate, the faster cannabis grows and the strength of the THC is therefore greater. Also, the strength varies according to which part of the plant is used, the most potent being the female seed. Legalisation would allow the user to purchase cannabis through licensed premises, rather than through the criminal underworld. Contamination with powders, including heroin, is not uncommon, and thus the relatively innocent user is introduced to harder drugs. Whether cannabis is addictive is still uncertain, particularly in its milder forms. Yours truly, MARY BUCK, (Probation officer, 1974-2000), Pond House, 30 Ham Common, Richmond, Surrey TW10 7JG.