To ask the Secretary of State for the Home Department what the average THC content of seized skunk cannabis was in the latest period for which figures are available; what the average THC content of cannabis seizures was (a) five, (b) 10 and (c) 20 years ago; and if she will make a statement.

The latest data from the Forensic Science Service Ltd (FSS) show that the average tetrahydrocannabinol (THC) content of mature flowering tops from plants, otherwise known as sinsemilla, seized and submitted to the FSS from the 1 January 2008 to the present day was 14.0%. By comparison, during the same period, the average THC content of traditional imported cannabis and cannabis resin was 12.5% and 5.5% respectively.

Information on average THC levels of cannabis available in the UK prior to 2008 is available in the Advisory Council on the Misuse of Drugs 2008 report 'Cannabis: Classification and Public Health', which can be found on the Home Office website via the following link:

http://www.homeoffice.gov.uk/drugs/acmd/reports-research/

This summarises data available at that time, including FSS data from 1995 to 2007 and data from the Home Office's Cannabis Potency Study 2008, published by the Home Office Scientific Development Branch. Information on average THC levels of cannabis prior to 1995 is not available.