Extraction of Antibiotics from Agricultural Wastewater

Abstract

Increasingly, swine, poultry, and other livestock are being raised in large confined animal-feeding operations (CAFO). Because of the close proximity of the animals to each other, there is a strong danger of disease spreading through the CAFO and destroying an entire herd. To reduce the likelihood of a costly epidemic, many operators feed milligram-per-kilogram quantities of antibiotics to the animals. In addition, antibiotics are used to increase the animals' rate of weight gain. Some of these antibiotics are not metabolized in the animals' digestive systems, and they end up in the CAFO wastewater. From there, they can be transported into surface and ground water. Concerns have been raised about widespread use of antibiotics accelerating the development of antibiotic resistant bacteria. A method has been developed for solid-phase extraction of eight antibiotics from a 123-mL sample of water. These antibiotics consisted of three tetracyclines, (tetracycline, oxytetracycline, chlortetracycline) and five sulfonilamides (sulfonamethazine, sulfamerazine, sulfathiazole, sulfachloropyridazine, and sulfadimethozine). The antibiotics that are quantified using liquid chromatography/mass spectrometry. Tetracyclines, as a class, exhibited losses of mass-to-charge (m/z) 17 and m/z 35, and a characteristic m/z 156 ion was identified for all five of the sulfonilamides. A linear extraction curve has been established for the tetracyclines from 0.2 to 5.0 micrograms per liter (mg/L), and for the sulfoniliamides from 0.1 to 5.0 mg/L. The extraction method has been applied to CAFO wastewater samples, and antibiotics have been detected.

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Lindsey, M.E., and Thurman, E.M., 2000, Extraction of Antibiotics from Agricultural Wastewater [abst.]: 220th ACS meeting, Washington, D.C., August 20-24, 2000.

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