Occurrence of Antibiotics in an Agricultural Watershed in South‐Central Idaho

Abstract

The polar organic compound integrative sampler (POCIS) is a tool that has been effectively used to passively sample organic pollutants over long periods in aquatic environments. In this study, POCIS were used to investigate the spatial and temporal occurrence of 21 antibiotics in irrigation return flows and upstream sites of an intensively managed agricultural watershed in southcentral Idaho. The antibiotic metabolite, erythromycin-H 2 O, and the antibiotics monensin, oxytetracycline, sulfadimethoxine, sulfamethazine, sulfamethoxazole, trimethoprim, and tylosin were detected at frequencies ranging from 3.1 to 62.5%, with monensin having the highest rate of detection. The fact that monensin was the most frequently detected compound indicates that it is entering return flows in runoff from fields that had received livestock manure or wastewater. Antibiotics (except oxytetracycline, sulfamethazine, and tylosin) were also detected at an upstream site that consisted of diverted Snake River water and is the source of irrigation water for the watershed. Therefore, even cropped soils that are not treated with manure are still receiving low-level antibiotics during irrigation events. This study provides the first set of evidence that surface waters within this agricultural watershed contain antibiotic residues associated with veterinary and human uses.

Measuring the occurrence of antibiotics in surface water adjacent to cattle grazing areas using passive samplers

“…There were two groups of veterinary pharmaceuticals in this study. Categorizing them was based on their eluting conditions from POCIS sorbent, their chemical classes and adaptability to solvents (Dungan et al, 2017). The group of analytes that were categorized as macrolide/penicillin in this study, included ampicillin, virginiamycin M1, tylosin, tiamulin, penillic acid, penicillin, novobiocin, monensin, erythromycin Anhydro-, erythromycin and ceftiofur.…”

“…Field-deployed POCIS were extracted sequentially for two groups of compounds and extracts combined using methods describe previously (Dungan et al, 2017). Macrolides and beta-lactams were measured first to minimize the risk of hydrolysis from methanol and formic acid.…”

Antimicrobial Resistance in the Environment

“…The occurrence of antibiotics was also evaluated in irrigation return flows and upstream waters from an agricultural watershed in Idaho (Dungan et al, 2017). A total of 21 antibiotics were measured using a polar organic compound integrative sampler.…”

The fate and effect of monensin during anaerobic digestion of dairy manure under mesophilic conditions

“…The widespread use and persistence of monensin have led to its detection in manure (0.3–4.5 mg/L) [ 9 , 10 ], soil (0.0004 μg/kg) [ 4 ], surface water (0.01–0.05 μg/L) [ 11 , 12 ], groundwater (0.04–0.39 μg/L) [ 13 ] and sediment (1.5–31.5 μg/kg) [ 12 ]. Monensin was the most frequently (63%) detected antibiotic in irrigation return flows of an intensively managed agricultural watershed in south-central Idaho [ 14 ]. The EC 50 of monensin in the aquatic environment is highly species dependent, ranging from 0.2 to 7.3 mg/L [ 15 ].…”