title: Fate and transport of atorvastatin and simvastatin drugs during conventional wastewater treatment.
abstract: 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.
authors.affiliation: Department of Civil & Environmental Engineering, University of Virginia, PO Box 400742, Charlottesville, VA 22904-4742, USA. kjottmar@gmail.com
authors.forename: Karl J
authors.initials: KJ
authors.lastname: Ottmar
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Colosi
authors.forename: James A
authors.initials: JA
authors.lastname: Smith
mesh_terms: D000069059:Atorvastatin; D018533:Biomass; D001711:Biotransformation; D006538:Heptanoic Acids / Q000737:chemistry / Q000378:metabolism*; D015233:Models, Statistical; D008970:Molecular Weight; D011758:Pyrroles / Q000737:chemistry / Q000378:metabolism*; D015203:Reproducibility of Results; D012722:Sewage / Q000382:microbiology; D019821:Simvastatin / Q000737:chemistry / Q000378:metabolism*; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism*
chemical_list: D006538:Heptanoic Acids; D011758:Pyrroles; D012722:Sewage; D014874:Water Pollutants, Chemical; D000069059:Atorvastatin; D019821:Simvastatin