| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4409796 | Chemosphere | 2012 | 6 Pages |
This research investigates the environmental behavior of two widely prescribed cholesterol-lowering statin drugs that are expected to be present at significant concentrations in wastewater influents, namely: atorvastatin and simvastatin. Batch biodegradation experiments suggest that both statins are well degraded during secondary treatment, and removal rates exhibit a substrate-enhancement model reflecting elements of both first-order behavior and cometabolism. Resulting biodegradation parameters are used in conjunction with literature sorption parameters to construct a mass-balance model of statin concentrations during conventional treatment. Model results exhibit excellent accuracy compared to measurements from a medium-sized WWTP in the Southeastern USA. Influent concentrations of 1.56 μg L−1 and 1.23 μg L−1 were measured for atorvastatin and simvastatin. Results also suggest that 85–90% of each drug is removed during conventional treatment, with sorption accounting for less than 10% of overall removal. Expected effluent concentrations are orders of magnitude less than previously reported ecotoxicity thresholds for both drugs. Overall, results suggest statin active ingredients do not pose a significant environmental threat. It is recommended that future work characterize the fate of statin metabolites and that the same mass-balance modeling approach be used to assess other highly-prescribed pharmaceutical drugs.
► We evaluated the biodegradation of two statin drugs in wastewater treatment. ► Biodegradation appears to follow a novel substrate-enhanced metabolic model. ► We developed a wastewater treatment model for sorption and biodegradation. ► Model was validated with a year-long sampling campaign at a treatment plant.
