Uncertainty-based concentration estimation of chlortetracycline antibiotics in swine farms and risk probability assessment for agricultural application of manure

Consideration of livestock farming practices is necessary for the reliable prediction of veterinary antibiotics concentrations in livestock manure and soil and characterization of their ecological risks. This study aims to predict concentrations of chlortetracycline (CTC) generated from slurry pit and evaluate its ecological risk in soil based on the European Medicine Agency guidelines by considering slurry pit farm practices such as cleaning water volume and those uncertainties. Additionally, sensitivity analysis was conducted on the exposure esti-mation of CTC in soil employing the Monte Carlo simulation. The predicted environmental concentrations of CTC in the slurry pit and soil were in a range of 0.54-5.64 mg/kgmanure and 3.42-67.59 mu g/kgsoil, respectively, for a 90 % confidence level. The predicted ranges included the measured values reported in previous studies. The probability of risk quotient (RQ) exceeding one was estimated at 9.3 % based on the Monte Carlo simulation. The four most influential factors on the exposure to CTC in soil were identified as nitrogen in fertilizer/compost, cleaning water volume, ratio of sick pigs requiring antibiotics, and pit emptying cycles. The results indicate that the ecological risk of CTC in the soil is possible and can be controlled by slurry pit farm practices.

Automated summary

This study predicts the concentrations of chlortetracycline in slurry pit and soil, evaluating ecological risks, based on livestock farming practices and uncertainties. The Monte Carlo simulation was used for sensitivity analysis, revealing key factors influencing CTC exposure in soil. The results suggest that ecological risks of CTC in soil can be controlled through appropriate slurry pit farm practices.