"Among the general population, use of powder cocaine is far more common than use of crack cocaine. Although crack cocaine use is relatively rare, it is associated with very problematic use and drug-related crime, predominantly among those also using opioids. Due to the often chaotic nature of users’ lives, it is likely that household surveys underestimate crack use. The last indirect estimate of problematic crack use in England puts the rate at 4.76 per 1000 population aged 15 to 64 years (Hay, Rael dos Santos, & Worsley, 2014). Cocaine (powder) is also the most seized stimulant in the UK, both in terms of number and quantity of seizures (see ST13). Having been 51% in 2003, the purity of domestic resale powder cocaine fell to 20% in 2009. However, it has risen since then and was 36% in 2014."

Source

UK Focal Point at Public Health England, United Kingdom Drug Situation: Focal Point Annual Report 2015 (2016), Annual Report to the European Monitoring Centre on Drugs and Drug Addiction, p. 52.
http://www.nta.nhs.uk/focalpo…
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