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

Concentrations and Risk Assessments of Antibiotics in an Urban-Rural Complex Watershed with Intensive Livestock Farming

Antibiotics used for the treatment of humans and livestock are released into the environment, whereby they pose a grave threat to biota (including humans) as they can cause the emergence of various strains of resistant bacteria. An improved understanding of antibiotics in the environment is thus vital for appropriate management and mitigation. Herein, surface water and groundwater samples containing antibiotics were analyzed in an urban-rural complex watershed (Cheongmi Stream) comprising intensive livestock farms by collecting samples across different time points and locations. The spatiotemporal trends of the residual antibiotics were analyzed, and ecological and antibiotic resistance-based risk assessments were performed considering their concentrations. The results showed that the concentrations and detection frequencies of the residual antibiotics in the surface water were affected by various factors such as agricultural activities and point sources, and were higher than those found in groundwater; however, frequent detection of antibiotics in groundwater showed that residual antibiotics were influenced by factors such as usage pattern and sewage runoff. Furthermore, few antibiotics posed ecological risks. The risk assessment methods adopted in this study can be applied elsewhere, and the results can be considered in the environmental management of residual antibiotics in the Cheongmi Stream watershed.

Strong links between load and manure and a comprehensive risk assessment of veterinary antibiotics with low KOW in intensive livestock farming watersheds

Various veterinary antibiotics (VAs) are used in large quantities as an essential component for intensive livestock farming, and can flow into the environment from various pollution sources. In this study, VAs in surface water and groundwater in the Gwangcheon stream watershed, an intensive livestock farming area in Korea, were analyzed using ultra-high-performance liquid chromatograph-quadrupole orbitrap high-resolution mass spectrometer with online solid phase extraction. Although the selected VAs are relatively mobile and have low K_OW values it is significant to assess their fates and ecological risks in the environment. The concentration of VAs in the surface water was higher than that in groundwater by approximately 23-fold, indicating that the former were directly introduced from pollution sources such as livestock manure. An analysis of the correlation between livestock manure production and the residuals of VAs in the stream showed a high linearity (R² > 0.70), confirming that livestock excreta significantly contributed to the VAs in the watershed. A combined evaluation of environmental behaviors and ecological risks of VAs was performed for the first time using persistence, bioaccumulation potential, and toxicity properties and risk quotient values of VAs. Trimethoprim showed persistence and a potential impact on the ecosystem. The cumulative risk quotient values at one sampling point exceeded 1 indicating that several VAs can cumulatively cause local risk. The risk assessment method considering pollution sources, different locations, and correlation analysis applied in this study will be useful in evaluating the impacts of trace pollutants in watersheds.

A review targeting veterinary antibiotics removal from livestock manure management systems and future outlook

Veterinary antibiotics (VAs) contamination has been considered as a worldwide environmental and health concern in recent decades. This paper reviewed the variability of contents of VAs and their release from the animal breeding industry into the surrounding environment along with the performance of the manure treatment technologies. The data collected revealed that VAs were mostly excreted in animal feces and observed in manure, soil, water, and sediment. The findings illustrate the disparity of VAs in excretion rates, consumption, and their residues in the environment with relatively high distribution for tetracyclines, fluoroquinolones, and sulfonamides. Anaerobic digestion has a capacity to remove of 73% VAs while manure composting and constructed wetlands can remove 84.7%, and 90% VAs. Due to the profound effect of antibiotics on the environment, further research and intensive management strategies for livestock manure need to be designed to improve the removal efficiency and manure management technologies.

Simultaneous determination of eight biogenic amines in the traditional Chinese condiment Pixian Douban using UHPLC-MS/MS

A UHPLC-MS/MS method was developed to simultaneously determine eight biogenic amines (BAs) in Pixian Douban. Under optimal conditions, the linear ranges of determination were 5-1000 μg/L (that of spermine was 8-1000 μg/L). Correlation coefficients ranged from 0.9955 to 0.9987. The limits of detection were 0.11-5.5 μg/L. The matrix effect and analytical performance of the present method were evaluated, and the eight BAs were analyzed by this method in 19 samples, indicating the potential pollution of BAs in chili oil Pixian Douban.