My Account: Log In | Join | Renew
Search
Author
Title
Vol.
Issue
Year
1st Page

Abstract

 

This article in JEQ

  1. Vol. 42 No. 1, p. 173-178
     
    Received: Apr 18, 2012
    Published: December 6, 2012


    * Corresponding author(s): ed.topp@agr.gc.ca
 View
 Download
 Alerts
 Permissions
 Share

doi:10.2134/jeq2012.0162

Accelerated Biodegradation of Veterinary Antibiotics in Agricultural Soil following Long-Term Exposure, and Isolation of a Sulfamethazine-degrading Microbacterium sp.

  1. Edward Topp *a,
  2. Ralph Chapmana,
  3. Marion Devers-Lamranib,
  4. Alain Hartmannc,
  5. Romain Martia,
  6. Fabrice Martin-Laurentb,
  7. Lyne Sabourina,
  8. Andrew Scotta and
  9. Mark Sumaraha
  1. a Agriculture and Agri-Food Canada, London, ON N5V 4T3 Canada
    b INRA, UMR 1347 Agroecologie, Pole Ecodur, EMFI, 17 rue Sully 21065 Dijon Cedex, France
    c INRA, UMR 1347 Agroecologie, Pole MERS, 17 rue Sully 21065 Dijon Cedex, France

Abstract

The World Health Organization has identified antibiotic resistance as one of the top three threats to global health. There is concern that the use of antibiotics as growth promoting agents in livestock production contributes to the increasingly problematic development of antibiotic resistance. Many antibiotics are excreted at high rates, and the land application of animal manures represents a significant source of environmental exposure to these agents. To evaluate the long-term effects of antibiotic exposure on soil microbial populations, a series of field plots were established in 1999 that have since received annual applications of a mixture of sulfamethazine (SMZ), tylosin (TYL), and chlortetracycline (CTC). During the first 6 yr (1999–2004) soils were treated at concentrations of 0, 0.01 0.1, and 1.0 mg kg−1 soil, in subsequent years at concentrations of 0, 0.1, 1.0, and 10 mg kg−1 soil. The lower end of this concentration range is within that which would result from an annual application of manure from medicated swine. Following ten annual applications, the fate of the drugs in the soil was evaluated. Residues of SMZ and TYL, but not CTC were removed much more rapidly in soil with a history of exposure to 10 mg/kg drugs than in untreated control soil. Residues of 14C-SMZ were rapidly and thoroughly mineralized to 14CO2 in the historically treated soils, but not in the untreated soil. A SMZ-degrading Microbacterium sp. was isolated from the treated soil. Overall, these results indicate that soil bacteria adapt to long-term exposure to some veterinary antibiotics resulting in sharply reduced persistence. Accelerated biodegradation of antibiotics in matrices exposed to agricultural, wastewater, or pharmaceutical manufacturing effluents would attenuate environmental exposure to antibiotics, and merits investigation in the context of assessing potential risks of antibiotic resistance development in environmental matrices.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © 2013. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.