This is the same old same old about how cannabis has become stronger and thus more 'dangerous' in recent years. It is sad to see the Guardian uncritically trotting this stuff out again. A bit of simple research (Google) shows (from last year):
http://news.bbc.co.uk/1/hi/progr...ama/
4101004.stm
The key points of the report which can be found at the EMCDDA website suggested that the changes in average strength of cannabis available may not be as big dramatic as some have claimed.
* The effective potency in nearly all countries has remained quite stable for many years at around 6-8 %. The only exception has been the Netherlands where, by 2001-2002, it had reached 16 %.
* The natural variation in the THC content between and within samples of herbal cannabis or cannabis resin at any one time and place far exceeds any long-term changes that may have occurred either in Europe or the USA
* Herbal cannabis produced by intensive indoor methods (e.g. hydroponic systems with artificial lighting, propagation by cuttings and control of day length) usually has higher THC levels than imported material
* The higher potency of herbal cannabis produced by indoor methods is a reflection of several factors: genetic, environmental and freshness.
