Measurement of oxytetracycline and emamectin benzoate in freshwater sediments downstream of land based aquaculture facilities in the Atlantic Region of Canada.
This study investigated the occurrence of oxytetracycline (OTC) and emamectin benzoate (EB) in sediments located near the effluent outfall from four freshwater aquaculture facilities in Atlantic Canada. While two facilities had no detectable concentrations of EB or OTC, two facilities had detectable concentrations of one or both of these chemicals. Concentrations ranged from <0.05-18 mg/kg to <0.01-2.5 mg/kg for OTC and EB respectively. Although these values could not be compared with freshwater toxicant values, some of the concentrations of EB and OTC detected were higher than LC(50) values calculated for marine invertebrates. OTC concentrations measured in this study are also of a magnitude which has been known to produce resistant bacteria.
Atlantic Ocean Watershed, Water Quality Monitoring and Surveillance Division, Water Science and Technology Branch, Environment Canada, 45 Alderney Dr., Dartmouth, NS, B2Y 2N6, Canada. benoit.lalonde@ec.gc.ca
Benoit A
BA
Lalonde
William
W
Ernst
Lyndsay
L
Greenwood
D017756:Aquaculture; D002170:Canada; D005618:Fresh Water; D019015:Geologic Sediments / Q000737:chemistry*; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000032:analysis; D010118:Oxytetracycline / Q000032:analysis*
D007559:Ivermectin; C108024:emamectin benzoate; D010118:Oxytetracycline