|WOODWARD, KATHERINE - Tufts University|
|GUTE, DAVID - Tufts University|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/25/2018
Publication Date: 7/29/2018
Citation: Woodward, K., Hakk, H., Lupton, S.J., Woodbury, B.L., Gute, D. 2018. Fate and transport of three antibiotics in laboratory batch partitioning studies using beef lagoon runoff water [abstract]. 2018 American Society of Agricultural and Biological Engineers Annual International Meeting. July 29-August 1, 2018. Detroit, MI. Paper #1800516.
Interpretive Summary: .
Technical Abstract: Antibiotics are used therapeutically during production of food animals to maintain herd health. Much of these administered antibiotics pass through the animal unchanged and enter the environment through manure management practices such as irrigation with feedlot runoff wastewater. The scientific community is concerned this antibiotic loading will alter the natural biota resulting in increased resistance, thereby making antibiotics that are critical for human and animal health ineffective. Therefore, cost-effective methods are needed to mitigate this environmental risk. The objective of this study was to characterize the partitioning of select antibiotic residues between the aqueous and sorbed phases on solids in runoff wastewater. Three radiolabeled antibiotics, i.e., [14C]-erythromycin (ERY), [3H]-chlortetracycline (CTC), and [3H]-monensin (MON), were selected for a laboratory batch partitioning study utilizing beef lagoon runoff wastewater. Liquid scintillation counting and combustion were used to quantify the radioactivity in the aqueous and sorbed fractions across time. Slightly more ERY sorbed to the suspended solids fraction than the aqueous fraction, and equilibrium conditions were achieved quickly, i.e., 2 hours. CTC partitioning occurred in two phases: a rapid sorption to the solids fraction between 0.5 and 8 hours with desorption into the aqueous fraction at 24 hours, suggesting degradation to more polar compounds. The most lipophilic antibiotic tested, MON, quickly and quantitatively sorbed into the suspended solids layer and remained in equilibrium with the aqueous fraction from 0.5 to 168 hours. The differences between these three antibiotics illustrate that variation between antibiotic behavior exists, making it appropriate to test large-use antibiotics. Additional studies are planned to quantify the efficacy of using binding agents to remove antibiotics from wastewater.