Characteristics of veterinary antibiotics in intensive livestock farming watersheds with different liquid manure application programs using UHPLC-q-orbitrap HRMS combined with on-line SPE

• Published in: The Science of the total environment 2020-12, Vol.749, p.142375, Article 142375
• Main Authors: Lee, Hyun-Jeoung, Ryu, Hong-Duck, Lim, Do Young, Chung, Eu Gene, Kim, Kyunghyun, Lee, Jae Kwan
• Format: Article
• Language: English
• Subjects: Agricultural watershed; Agriculture; Animals; Anti-Bacterial Agents; Chromatography, High Pressure Liquid; High-resolution mass spectrometry; Liquid manure application; Livestock; Livestock excreta; Manure - analysis; Monitoring; Republic of Korea
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2020.142375

Composted livestock manures, in both solid and liquid form, are used as fertilizers in cropland. However, excess solid and liquid manures in agricultural watersheds are considered as nonpoint pollution sources because of their high nutrient and heavy metal contents of, as well as their antibiotic contents, especially veterinary antibiotics (VAs). In this study, 21 VAs under nine classes (i.e., cephems, ionophores, lincosamides, penicillins, pleuromutilins, quinolones, streptogramins, sulfonamides, and tetracyclines) found in agricultural watersheds were simultaneously analyzed via UHPLC-q-orbitrap high-resolution mass spectrometry using an on-line solid-phase extraction system. The residues of VAs in the surface water of two intensive livestock rearing watersheds (Cheongmi and Gwangcheon streams) in Korea were successfully quantified, and the values were found to range from 1.84 ± 0.42 ng L−1 to 835.6 ± 31.9 ng L−1. Time lags of 2–3 months were observed between the periods of liquid manure application and the periods with the maximum concentrations of VAs. In both watersheds, samples from points close to areas with extensive application of liquid manure exhibited high concentrations of most of the 21 VAs. Between the watersheds, the one with heavier application of liquid manure showed higher concentrations of the target VAs. To the best of our knowledge, this study represents the first attempt at evaluating the correlation between liquid manure application and environmental occurrence of VAs in surface water. The findings reveal that liquid manure application plays an important role in introducing VAs into aquatic environments. [Display omitted] •Spatiotemporal trends of veterinary antibiotics in farming watersheds were analyzed.•Agricultural activities affected seasonal variations of antibiotic concentrations.•Areas with heavier liquid manure application showed higher antibiotic concentrations.•Liquid manure application can affect residual antibiotic concentrations.