The present paper deals with the wastewater analysis with the aim to define the consumption of drugs in individual cities. Urinary bio-markers of methamphetamine, cocaine, cannabis and ecstasy use were analyzed by liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS). The data obtained were compared between selected Slovak towns as well as within cities in Europe. The highest specific loads of THC-COOH were analyzed in Bratislava (Central WWTP – 38 mg/day/1000 inhabitants; Petržalka – 43 mg/day/1000 inh.). The measured results indicate a high consumption of methamphetamine in particular in the cities of Dunajská Streda (860 mg/day/1000 inh.), Trnava (680 mg/day/1000 inh.) and Bratislava (188 mg/day/1000 inh.), thus these cities reported one of the highest methamphetamine consumption in Europe. In our analyzed data are reported also specific consumption values for ecstasy, cocaine, tramadol as well as number of cigarettes per capita and day smoked for selected cities in Slovakia.

Key words: sewage – drug analysis