Location: Meat Safety & Quality ResearchTitle: Measuring the occurrence of antibiotics in surface water adjacent to cattle grazing areas using passive samplers
|NADERI BENI, NASRIN - University Of Nebraska|
|SNOW, DANIEL - University Of Nebraska|
|MITTELSTET, AARON - University Of Nebraska|
|MESSER, TIFFANY - University Of Nebraska|
|BARTELT-HUNT, SHANNON - University Of Nebraska|
Submitted to: Science of the Total Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/27/2020
Publication Date: 7/15/2020
Citation: Naderi Beni, N., Snow, D.D., Berry, E.D., Mittelstet, A.R., Messer, T.L., Bartelt-Hunt, S. 2020. Measuring the occurrence of antibiotics in surface water adjacent to cattle grazing areas using passive samplers. Science of the Total Environment. 726:138296. https://doi.org/10.1016/j.scitotenv.2020.138296.
Interpretive Summary: Antibiotics used to treat livestock can pass through the animal and be excreted in their feces and urine. Animal manure is an important source of nutrients and is commonly applied to cropland as fertilizer. Runoff from heavy rains may transport antibiotics from manure-amended fields or pastures into surface water. Antibiotics in the environment are a concern because of the potential development of resistance in pathogenic bacteria, which can reduce the ability of antibiotics to treat infections in animals and humans. In this study, the occurrence of 24 commonly-used veterinary antibiotics was evaluated in the water of a stream that is fed by groundwater and traverses a cattle production operation. Ten antibiotics were detected, but only one of these antibiotics was prescribed to livestock at the facility. The lack of detection of the prescribed antibiotics may be to their adsorption to soil or their degradation in the environment. The detection of non-prescribed antibiotics may be attributable to the environmental persistence of previously-used antibiotics, atmospheric deposition from other nearby livestock production facilities or industrial sites, antibiotics in the groundwater, and/or the natural production of some antibiotics by soil bacteria.
Technical Abstract: A wide variety of antibiotics and other pharmaceuticals are used in livestock production systems and residues can be passed to the environment, often unmetabolized, after use and excretion. Antibiotic residues may be transported from manure-treated soils via runoff and are also capable of reaching surface and groundwater systems through a variety of pathways. The occurrence and persistence of antibiotics in the environment is a concern due to the potential for ecological effects and proliferation of environmental antibiotic resistance in pathogenic organisms. In the present study, the occurrence and seasonal variation of 24 commonly-used veterinary antibiotics was evaluated in surface water adjacent to several livestock production systems using Polar Organic Chemical Integrative Samplers (POCIS). Uptake rates for all compounds, nine of which have not been previously reported, were measured in the laboratory to permit estimation of changes in the time-weighted average (TWA) antibiotic concentrations during exposure. The antibiotics detected in POCIS extracts included sulfadimethoxine, sulfamethoxazole, trimethoprim, sulfamerazine, sulfadiazine, lincomycin, tiamulin, erythromycin, erythromycin anhydro- and monensin. The maximum TWA concentration belonged to sulfadiazine (22.2 ng/L) in the August-September sampling period and coincided with the highest number of precipitation events. With the exception of monensin that accumulated over the stream path, none of the detected antibiotics were prescribed to livestock at the facility. The detection of antibiotics may be attributable to the environmental persistence of previously used antibiotics, atmospheric deposition from other nearby livestock production sites or industrial uses, the use of copper sulfate to treat for algae near the sampling location, and/or the natural production of some antibiotics.