Detection of pharmaceutical contaminations of river, pond, and tap water from Cologne (Germany) and surroundings

A method for the simultaneous determination of polar pharmaceutical compounds in water is presented. Samples from 27 rivers and ponds were investigated for contents of Gemfibrocil, a lipid blood regulating compound, Clofibric acid, a metabolite of lipid regulating compounds (Clofibrat, Etofibrat, Etofyllinclofibrat), antirheumatics (Diclofenac, Ibuprofen, Ketoprofen, Indomethacin, Fenoprofen) and Sarkosin-N-(phenylsulfonyl) (SPS), a metabolite of a corrosion inhibiting agent. In addition water samples were investigated for some main metabolites of Ibuprofen, 2-[4-(2-hydroxy-2-methylpropyl)phenyl]propionic acid (hydroxy-ibuprofen) and 2-[4-(2-carboxypropyl)phenyl]propionic acid (carboxy-ibuprofen), which are excreted after oral intake. For gas chromatographic analysis the drugs were converted into their methyl-derivatives by "on column" reaction with TMSH, TMAH and "pre column" with diazomethane. The detection limits with TMSH were in the same range or lower than those with diazomethane or TMAH. The compound most frequently found was SPS which was only absent in waters with natural surroundings. Diclofenac could be detected in 10 out of 27 water samples in concentrations of up to 15 mug/l. In contrast, none of the pharmaceuticals investigated were present in 8 drinking water samples from Cologne and surroundings. Though concentrations measured were far below pharmacological doses, the data suggest a steady flux of these drugs into the environment.