Environmental fate and microbial effects of monensin, lincomycin, and sulfamethazine residues in soil

Authors: D'ALESSIO, MATTEO - University Of Nebraska; Durso, Lisa; Miller, Daniel; Woodbury, Bryan; RAY, CHITTARANJAN - University Of Nebraska; SNOW, DANIEL - University Of Nebraska

Submitted to: Environmental Pollution
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/28/2018
Publication Date: 3/1/2019
Citation: D’Alessio, M., L. Durso, D. N. Miller, B. Woodbury, C. Ray and D. D. Snow. 2019. Environmental fate and microbial effects of monensin, lincomycin, and sulfamethazine residues in soil. Environmental Pollution 246:60-68. https://doi.org/10.1016/j.envpol.2018.11.093
DOI: https://doi.org/10.1016/j.envpol.2018.11.093

Interpretive Summary: The movement of veterinary antibiotics and nitrate through soils may depend upon the prevailing soil microbial conditions (aerobic, anaerobic, and denitrifying). In turn, some veterinary antibiotics may limit important soil processes at high concentrations including denitrification. To investigate these relationships, three common antibiotics (monensin, lincomycin, and sulfamthazine) individually and in combination were introduced along with nitrate to soil columns experiencing aerobic, anaerobic, and denitrifying conditions. Antibiotic movement varied between compounds and affected nitrogen transport through the column. At high enough concentrations of the three-antibiotic mixture, denitrification was inhibited, while lower concentrations of individual antibiotic had limited effect. Microbial populations in the upper parts of the soil cores were altered during the experiment. These results suggest that the occurrence of veterinary antibiotics can interrupt nitrogen cycling in soils receiving wastewater or manure, and that longer term changes in microbial populations can result at higher concentrations.

Technical Abstract: The mobility and effect to soil microbial communities of three antibiotics (monensin, lincomycin and sulfamethazine) combined with nitrate was investigated under aerobic, reduced, and denitrifying conditions using soil columns. Monensin was constantly found to be the least mobile. Lincomycin and sulfamethazine were detected in column effluent, but their concentrations decreased during transport through the columns. Sorption and biodegradation are likely to be the primary factors leading to antibiotics' attenuation. The addition of antibiotic residues highly impacted the nitrogen cycle. During antibiotic injection, nitrate concentrations progressively decreased below the analytical detection limit, while nitrite concentrations increased. During flush-out, nitrate and nitrite concentrations increased and decreased, respectively, and resumed to pre-dosage levels. Inhibition of denitrification was observed after injection of the antibiotic mixture. Proteobacteria, bacteroidetes, actinobacteria, and chloroflexi were the predominant phyla observed throughout the study. Injection of antibiotics resulted in a long term change in microbial community composition in the upper portion of the columns while a temporary change occurred in the lower portion. These results suggest that the occurrence of veterinary antibiotics can interrupt nitrogen cycling in soils receiving wastewater or manure, and that longer term changes in microbial populations can result at higher environmentally relevant application concentrations.