The designer drugs seen in Finland in the past have been mainly stimulants. The first case of a fatal overdose caused by the opioid U-47700 was seen last spring and since then it has accounted for at least four more deaths.
"Of course, the stimulants are dangerous drugs, but they don't cause overdose fatalities the way that opioid do," points out Professor Ilkka Ojanperä of the National Institute for Health and Welfare.
U-47700 is significantly more potent than morphine. It was originally created by the pharmaceutical industry and it has been possible to purchase it online. The drug was only recently classed as illegal in Finland.
Customs officials have indications of how and from where the drug is arriving in the country.
"The vast majority of designer drugs are carried by couriers or by mail. They are often produced in Asia, mainly in China," explains Enforcement Director Hannu Sinkkonen of Finnish Customs. "They are not necessarily illegally manufactured, as these designer drugs are often made for medical use and, for example in China, may not be banned substances."