title: Behaviour of pharmaceuticals in spiked lake sediments - effects and interactions with benthic invertebrates.
abstract: The behaviour and effects of atorvastatin (ATO), carbamazepine (CBZ), and 17α-ethinylestradiol (EE2) were investigated in spiked lake sediments, at concentrations up to 56.5 mg kg(-1)dry weight (dw), with the benthic invertebrates Chironomus dilutus and Hyalella azteca. Desorption constants were calculated in the presence and absence of animals, using linear isotherms, yielding K(d) values of 28.2, 189.0 and 125.1 L kg(-1) (ATO), 73.7, 201.7 and 263.2 L kg(-1) (CBZ), and 114.9, 114.2 and 519.2 L kg(-1) (EE2) for C. dilutus, H. azteca, and without animals, respectively. For ATO and CBZ, K(d) values were smaller in the presence of C. dilutus, indicating greater desorption to the overlying water from bioturbation, which is consistent with the predominantly benthic occurrence of C. dilutus compared to H. azteca. In contrast, due to its greater hydrophobicity, bioturbation did not significantly affect desorption of EE2. No significant toxicity was observed, indicating decreased bioavailability of the chemicals sorbed to sediments compared with water-only toxicity assays.
authors.affiliation: Aquatic Ecosystem Protection Research Division, Water Science and Technology Directorate, Environment Canada, Burlington, Ontario, Canada L7R 4A6. eve.gilroy@bell.net
authors.forename: Ève A M
authors.initials: ÈA
authors.lastname: Gilroy
authors.forename: Vimal K
authors.initials: VK
authors.lastname: Balakrishnan
authors.forename: Keith R
authors.initials: KR
authors.lastname: Solomon
authors.forename: Ed
authors.initials: E
authors.lastname: Sverko
authors.forename: Paul K
authors.initials: PK
authors.lastname: Sibley
mesh_terms: D033304:Amphipoda / Q000187:drug effects*; D000818:Animals; D002683:Chironomidae / Q000187:drug effects*; D004350:Drug Residues / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity*; D054750:Ecotoxicology; D019015:Geologic Sediments / Q000737:chemistry*; D060106:Lakes / Q000737:chemistry*