Analysis, occurence and removal of nine pharmaceuticals in wastewaters from a municipal wastewater treatment plant

Abstract

The effluents from the municipal wastewater treatment plants (WWTPs) are a major source of release of pharmaceuticals into the aquatic environment. The occurrence and removal efficiency of 9 pharmaceutical compounds of several classes in the WWTP of Bucharest were investigated using 24 h flow proportional composite influent and effluent samples. The compounds monitored during 9 days period were 6 antibiotics (trimethoprim, norfloxacin, ciprofloxacin, azithromycin, sulphametoxazole, erythromycin), an antiinflammatory drug (acetaminophen), an anticonvulsant (carbamazepine) and a nervous stimulant (caffeine). The analytes were identified and quantified using solidphase extraction and triple quadrupole LCMS/MS. All of the monitored compounds, except norfloxacin and erythromycin, were detected in influent and effluent wastewater. Acetaminophen (up to 30.16 μgL1) and caffeine (up to 74.54 μgL1) were the most abundant pharmaceutical compounds in untreated wastewater. Different compounds were removed to different extent in the WWTP, ranging from 0% for trimethoprim and carbamazepine to 95% for acetaminophen. Of all the antibiotics, ciprofloxacin although detected in the highest concentrations in the influent, in the range 0.90 – 4.97 μgL1 was removed comparatively more efficiently. Ciprofloxacin could have adverse effects on microorganism involved in biological treatment process and the others antibiotics escape WWTP processing, contaminating the receiving water bodies