Drug availability and drug markets

Drug seizures

Data on drug seizures relate to all seizures made in each country during the year by all law enforcement agencies (police, customs, national guard, etc.). Caution is required in relation to double-counting that might occur within a country – although it is usually avoided – between various law enforcement agencies.

Seized quantities of cannabis, heroin, cocaine and amphetamine are provided in kilograms, of LSD in doses, and of ecstasy in tablets. Quantities seized may fluctuate from one year to another due to a small number of large seizures. For this reason, the numbers of seizures are usually considered as a better indicator of trends. In all countries, they include a major proportion of small seizures from the retail level of the market.

For more information see: Information map on law enforcement sources.

Drug prices

Street prices of cannabis, heroin, cocaine and amphetamine are provided in Euros per gram, of LSD in Euros per unit/dose, and of ecstasy in Euros per tablet. Data on prices come from a range of different sources the comparability of which is not always known. For example, the type of information systems (police sources, surveys among drug users, etc.) and the sampling strategies used to produce data on the price of illicit drugs at retail level do vary considerably across countries.

Data presented here are submitted to the EMCDDA as being national and annual, as well as referring to the retail level of the market (street level). Some caution is however required when analysing these data as they might, for some of them, present reliability problems. In some cases, they come from local rather than national monitoring systems, and/or from ad hoc non-repeated measures. There is also much uncertainty on the method used to calculate the averages – whether weighted or simple means are being used.

Drug purity/potency

For the time being the only data presented here are those on cannabis potency. The potency of cannabis products is equivalent to the D⁹-tetrahydrocannabinol (THC) content, where THC is the primary active constituent in cannabis. It is expressed in percent of THC. Cannabis potency is provided for herbal cannabis and cannabis resin separately. Whenever possible a further distinction is made between different types of herbal cannabis; however, caution is required here since these distinctions are not always clear.

As with data on prices, the data presented here are submitted to the EMCDDA as being national and annual, as well as referring to the retail level of the market (street level). Some caution in relation to reliability issues is required when analysing these data, since they may come from local or from ad-hoc non-repeated measures rather than national monitoring systems. Some of them are not representative of the retail level and are based on the analysis of all seizures of cannabis made in one country. Another source of variation across countries is the type of information systems and the sampling strategies used to produce data on cannabis potency and the way in which ‘average purity’ is calculated is often unclear.

There are analytical difficulties in the precise and accurate determination of THC; and standards of laboratory analysis might also vary between and within countries.

For more information see the EMCDDA Insights 6 ‘An overview of cannabis potency in Europe’.