About Us | Help Videos | Contact Us | Subscriptions

Journal of Environmental Quality Abstract - Special Section: Antibiotics in Agroecosystems: State of the Science

Evaluation of Monensin Transport to Shallow Groundwater after Irrigation with Dairy Lagoon Water


This article in JEQ

  1. Vol. 45 No. 2, p. 480-487
    Received: May 29, 2015
    Accepted: Sept 19, 2015
    Published: January 22, 2016

    * Corresponding author(s): sjparikh@ucdavis.edu
Request Permissions

  1. Sarah C. Hafnera,
  2. Thomas Hartera and
  3. Sanjai J. Parikh *a
  1. a Dep. of Land, Air and Water Resources, Univ. of California, One Shields Ave., Davis, CA 95616
Core Ideas:
  • Changes in groundwater chemistry can be observed within days of field irrigation.
  • Shallow aquifer with sandy soil presents a vulnerable site for contaminant transport.
  • Monensin is not rapidly transported to groundwater after a single irrigation event.
  • Leakage from waste storage systems results in monensin groundwater contamination


Animal waste products from concentrated animal feeding operations are a significant source of antibiotics to the environment. Monensin, an ionophore antibiotic commonly used to increase feed efficiency in livestock, is known to have varied toxicological effects on nontarget species. The current study builds on prior studies evaluating the impact of dairy management on groundwater quality by examining the transport of monensin in an agricultural field with coarse-textured soils during irrigation with lagoon wastewater. The dairy is located in California’s San Joaquin Valley, where groundwater can be encountered <5 m below the surface. Groundwater samples were collected from a network of monitoring wells installed throughout the dairy and adjacent to irrigated fields before and after an irrigation event, which allowed for measurement of monensin potentially reaching the shallow groundwater as a direct result of irrigation with lagoon water. Monensin was extracted from water samples via hydrophilic–lipophilic balance solid-phase extraction and quantified with liquid chromatography-mass spectrometry. Irrigation water was found to contain up to 1.6 μg L−1 monensin, but monensin was only detected in monitoring wells surrounding the waste storage lagoon. Water chemistry changes in the wells bordering the irrigated field suggest that up to 7% of irrigation water reached groundwater within days of irrigation. The study suggests that contamination of groundwater with monensin can occur primarily by compromised waste storage systems and that rapid transport of monensin to groundwater is not likely to occur from a single irrigation event.

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

Copyright © 2016. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.