"Insights into the use of new drugs are provided by the 2014 Flash Eurobarometer on young people and drugs, a telephone survey of 13,128 young adults aged 15–24 in the 28 EU Member States. Although primarily an attitudinal survey, the Eurobarometer includes a question on the use of ‘substances that imitate the effects of illicit drugs’.
"Currently, these data represent the only EU-wide information source on this topic, although for methodological reasons caution is required when
interpreting the results. Overall, 8% of respondents reported lifetime use of such substances, with 3% reporting use in the last year. This represents an increase from the 5% reporting lifetime use in a similar survey in 2011. Of those reporting use in the last year, 68% had obtained the substance from a friend.
"An increasing number of countries are including new psychoactive substances in their general population surveys, though differences in methods and questions limit the comparability of the results between countries. Since 2011, 11 European countries have reported national estimates of the use of new psychoactive substances (not including ketamine and GHB). For the age group covered in the Flash Eurobarometer study, younger adults (aged 15–24), last year prevalence of use of these substances ranges from 0.0% in Poland to 9.7% in Ireland. Survey data for the United Kingdom (England and Wales) are available on the use of mephedrone. In the most recent survey (2014/15), last year use of this drug among young people aged 16 to 24 was estimated at 1.9 %; this figure was the same as the previous survey, but down from 4.4% in 2010/11, before control measures were introduced. In 2014, a survey in Finland estimated last year use of synthetic cathinones to be 0.2% among young people aged 15 to 24, while in France an estimated 4% of 18- to 34-year-olds reported having ever smoked synthetic cannabinoids."

Source

European Monitoring Centre for Drugs and Drug Addiction (2016), European Drug Report 2016: Trends and Developments, Publications Office of the European Union, Luxembourg, p. 47.
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