Led by the sacked government drugs adviser David Nutt with colleagues from the breakaway Independent Scientific Committee on Drugs, the study says that if drugs were classified on the basis of the harm they do, alcohol would be class A, alongside heroin and crack cocaine…

Overall, alcohol scored 72 – against 55 for heroin and 54 for crack. The most dangerous drugs to their individual users were ranked as heroin, crack and then crystal meth. The most harmful to others were alcohol, heroin and crack in that order…

For overall harm, the other drugs examined ranked as follows: crystal meth (33), cocaine (27), tobacco (26), amphetamine/speed (23), cannabis (20), GHB (18), benzodiazepines (15), ketamine (15), methadone (13), butane (10), qat (9), ecstasy (9), anabolic steroids (9), LSD (7), buprenorphine (6) and magic mushrooms (5).