Fluoroquinolones and sulfonamides in sewage sludge compost and their uptake from soil into food plants

Sewage sludge compost can be a source of nutrients for plants and contamination by pharmaceutical products. In this study the presence of some widely used pharmaceuticals in sewage sludge and its compost –namely ciprofloxacin C17H18FN3O3, ofloxacin C18H20FN3O4, norfloxacin C16H18FN3O3, sulfadimethoxine C12H14N4O4S and sulfamethoxazole C10H11N3O3S – was shown. In several sewage sludge samples their concentrations exceeded the relevant trigger values for manure. The highest concentrations of ciprofloxacin, ofloxacin and norfloxacin in the compost ready for commercialization sufficiently exceeded the threshold concentration – 1 μg/kg – for pharmaceuticals in soil. The values of the highest detected concentrations of these pharmaceuticals in compost were respectively 70, 64 and 8 μg/kg.  The uptake of these pharmaceuticals was demonstrated from both sandy and loamy soils into food plants such as carrot (Daucus carota L), potato (Solanum tuberosum L) and wheat (Triticum vulgare L).     Key words: Soil pollution, plant uptake, pharmaceuticals.