Journal
CHEMOSPHERE
Volume 134, Issue -, Pages 504-511Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.chemosphere.2014.08.050
Keywords
Antibiotic; Amphenicol; Macrolide; Hydrolysis; Degradation
Categories
Funding
- Murdock grant, Washington State University Center for Sustaining Agriculture
- Natural Resources BIOAg program
- Washington State University, College of Agricultural, human, and Natural Resources Sciences, Agricultural Research Center
- STAR - U.S. Environmental Protection Agency (EPA) [FP-91714401]
Ask authors/readers for more resources
Antibiotics that enter the environment can present human and ecological health risks. An understanding of antibiotic hydrolysis rates is important for predicting their environmental persistence as biologically active contaminants. In this study, hydrolysis rates and Arrhenius constants were determined as a function of pH and temperature for two amphenicol (chloramphenicol and florfenicol) and two macrolide (spiramycin and tylosin) antibiotics. Antibiotic hydrolysis rates in pH 4-9 buffer solutions at 25 degrees C, 50 degrees C, and 60 degrees C were quantified, and degradation products were characterized. All of the antibiotics tested remained stable and exhibited no observable hydrolysis under ambient conditions typical of aquatic ecosystems. Acid- and base-catalyzed hydrolysis occurred at elevated temperatures (50-60 degrees C), and hydrolysis rates increased considerably below pH 5 and above pH 8. Hydrolysis rates also increased approximately 1.5- to 2.9-fold for each 10 degrees C increase in temperature. Based on the degradation product masses found, the functional groups that underwent hydrolysis were alkyl fluoride, amide, and cyclic ester (lactone) moieties: some of the resultant degradation products may remain bioactive, but to a lesser extent than the parent compounds. The results of this research demonstrate that amphenicol and macrolide antibiotics persist in aquatic systems under ambient temperature and pH conditions typical of natural waters. Thus, these antibiotics may present a risk in aquatic ecosystems depending on the concentration present. (C) 2015 Published by Elsevier Ltd.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available