title: Seasonal occurrence of antibiotics and a beta agonist in an agriculturally-intensive watershed.
abstract: We evaluated the occurrence of 12 veterinary antibiotics and a beta agonist over spatial and temporal scales in Shell Creek, an intensively agricultural watershed in Nebraska, using Polar Organic Chemical Integrative Samplers (POCIS). Twelve pharmaceuticals were detected with concentrations ranging from 0.0003 ng/L to 68 ng/L. The antibiotics measured at the highest time-weighted average concentrations were lincomycin (68 ng/L) and monensin (49 ng/L), and both compounds were detected at increased concentrations in summer months. Analysis of variance indicates that mean concentrations of detected pharmaceuticals have no significant (p > 0.01) spatial variation. However, significant temporal differences (p < 0.01) were observed. This study demonstrates the utility of passive samplers such as POCIS for monitoring ambient levels of pharmaceuticals in surface waters.
authors.affiliation: Department of Civil Engineering, University of Nebraska-Lincoln, United States.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Jaimes-Correa
authors.affiliation: Water Sciences Laboratory, Nebraska Water Center & School of Natural Resources, University of Nebraska-Lincoln, United States.
authors.forename: Daniel D
authors.initials: DD
authors.lastname: Snow
authors.affiliation: Department of Civil Engineering, University of Nebraska-Lincoln, United States. Electronic address: sbartelt2@unl.edu.
authors.forename: Shannon L
authors.initials: SL
authors.lastname: Bartelt-Hunt
mesh_terms: D000318:Adrenergic beta-Agonists / Q000032:analysis*; D057914:Agricultural Irrigation; D000900:Anti-Bacterial Agents / Q000032:analysis*; D004784:Environmental Monitoring; D009329:Nebraska; D009930:Organic Chemicals / Q000737:chemistry; D012621:Seasons; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000318:Adrenergic beta-Agonists; D000900:Anti-Bacterial Agents; D009930:Organic Chemicals; D014874:Water Pollutants, Chemical
keywords: Agriculture; POCIS; Veterinary pharmaceuticals