Author
HENDERSON, KERI - IA STATE UNIVERSITY | |
Moorman, Thomas | |
COATS, JOEL - IA STATE UNIVERSITY |
Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 11/19/2007 Publication Date: 12/26/2007 Citation: Henderson, K.L., Moorman, T.B., Coats, J.R. 2007. Mobility of Tylosin and Enteric Bacteria in Soil Columns. In: D.S. Aga, editor. Fate of Pharmaceuticals in the Environment and in Water Treatment Systems. Boca Raton, FL: CRC Press. p. 167-178. Interpretive Summary: Producers regularly use antibiotics as supplements in animal feed and water to increase weight gain and prevent diseases among their livestock. Pathogenic bacteria and antibiotics carried in the manure may result in nonpoint source pollution of ground or surface waters. This study examined the leaching of the enteric bacteria Escherichia coli and Enterococcus species (sp.) and the macrolide antibiotic, tylosin, through intact soil columns. Soil columns were obtained from a production field that had not received manure in the last 20 years. Water was applied to simulate four rainfall events. Trace amounts of tylosin leached in the loam soil, with an average of 0.8 nanograms/milliliter (ng/mL) total tylosin detected in the leachate. E. coli and Enterococcus were frequently present in the leachate at numbers exceeding the recreatiuonal water quality limits. This suggests that rainfall immediately following manure application could transport both bacteria and antibiotic residues to tile drainage systems. This study helps scientists and extension personnel to understand the environmental risks associated with manure application. Technical Abstract: To maximize production, producers regularly use antibiotics as supplements in animal feed and water to increase weight gain and prevent diseases among their livestock, which may result in nonpoint source pollution of ground or surface waters. This study examined the leaching of the enteric bacteria Escherichia coli and Enterococcus sp. and the macrolide antibiotic, tylosin, through intact soil columns. Soil columns were obtained from a production field that had not received manure in the last 20 years. Water was applied to simulate four rainfall events. Tylosin leached in the loam soil, with an average of 0.8 ng/mL total tylosin detected in the leachate. Tylosin D was the predominant factor present in the leachate. E. coli and Enterococcus were frequently present in the leachate at numbers exceeding the recreational water quality limits. This suggests that rainfall immediately following manure application could transport both bacteria and antibiotic residues to tile drainage systems. |