"Reflecting their use as legal replacements for cocaine, amphetamine and other controlled stimulants, there were more than 23 000 seizures of synthetic cathinones reported from across Europe in 2016 (Figure 3). These account for almost one-third of the total number of seizures of new substances over the year, and amounted to almost 1.9 tonnes, making synthetic cathinones the most commonly seized new psychoactive substances by quantity in 2016. The EMCDDA is currently monitoring 130 of these substances, including 14 that were reported for the first time in 2016 and 12 during 2017. Synthetic cathinones are generally found in powder form. The five most commonly seized cathinones in 2016 were alpha-PVP, 4-chloromethcathinone, 3-chloromethcathinone, 4-methyl-N,N-dimethylcathinone and 3-methylmethcathinone. The top five cathinones detected in powders were 4 chloromethcathinone (890 kg), 4-chloroethcathinone (247 kg), N-ethylhexedrone (186 kg), 3-methylmethcathinone (126 kg) and mexedrone (50 kg). In recent years, there have been indications of increasing interest in making synthetic cathinones in Europe, including seizures of precursors, equipment and illicit laboratories used to make mephedrone (which is now under international control), as well as 4-chloromethcathinone and 3-chloromethcathinone."
European Monitoring Centre for Drugs and Drug Addiction (2018), Fentanils and synthetic cannabinoids: driving greater complexity into the drug situation. An update from the EU Early Warning System (June 2018), Publications Office of the European Union, Luxembourg.