title: Fate of pharmaceutical compounds in hydroponic mesocosms planted with Scirpus validus.
abstract: A systematic approach to assess the fate of selected pharmaceuticals (carbamazepine, naproxen, diclofenac, clofibric acid and caffeine) in hydroponic mesocosms is described. The overall objective was to determine the kinetics of depletion (from solution) and plant uptake for these compounds in mesocosms planted with S. validus growing hydroponically. The potential for translocation of these pharmaceuticals from the roots to the shoots was also assessed. After 21 days of incubation, nearly all of the caffeine, naproxen and diclofenac were eliminated from solution, whereas carbamazepine and clofibric acid were recalcitrant to both photodegradation and biodegradation. The fact that the BAFs for roots for carbamazepine and clofibric acid were greater than 5, while the BAFs for naproxen, diclofenac and caffeine were less than 5, implied that the latter two compounds although recalcitrant to biodegradation, still had relatively high potential for plant uptake. Naproxen was sensitive to both photodegradation (30-42%) and biodegradation (>50%), while diclofenac was particularly sensitive (>70%) to photodegradation alone. No significant correlations (p > 0.05) were found between the rate constants of depletion or plant tissue levels of the pharmaceuticals and either log Kow or log Dow.
authors.affiliation: DHI-NTU Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 CleanTech 1, #06-08, Singapore 637141, Singapore. dqzhang@ntu.edu.sg
authors.forename: Dong Qing
authors.initials: DQ
authors.lastname: Zhang
authors.forename: Richard M
authors.initials: RM
authors.lastname: Gersberg
authors.forename: Tao
authors.initials: T
authors.lastname: Hua
authors.forename: Junfei
authors.initials: J
authors.lastname: Zhu
authors.forename: Manish Kumar
authors.initials: MK
authors.lastname: Goyal
authors.forename: Wun Jern
authors.initials: WJ
authors.lastname: Ng
authors.forename: Soon Keat
authors.initials: SK
authors.lastname: Tan
mesh_terms: D001673:Biodegradation, Environmental; D002220:Carbamazepine / Q000032:analysis / Q000378:metabolism; D002995:Clofibric Acid / Q000032:analysis / Q000378:metabolism; D029785:Cyperaceae / Q000378:metabolism / Q000502:physiology*; D004008:Diclofenac / Q000032:analysis / Q000378:metabolism; D018527:Hydroponics; D007700:Kinetics; D004364:Pharmaceutical Preparations / Q000032:analysis* / Q000378:metabolism; D010782:Photolysis; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
chemical_list: D004364:Pharmaceutical Preparations; D014874:Water Pollutants, Chemical; D004008:Diclofenac; D002220:Carbamazepine; D002995:Clofibric Acid
keywords: Log K(ow); Pharmaceuticals; Phytoremediation; S. validus; Uptake; Wetland