**4. Conclusions**

This study evaluated the adsorption and migration capacity of lincomycin, monensin and roxarsone in di fferent soil environments and their toxic e ffects on diverse environmental organisms. Moderate soil mobility and high water solubility exhibited by lincomycin could assist drug transfer and accumulation in various environments, and may cause certain problems after enrichment. Roxarsone was moderately mobile and its ecotoxicity implied that it is a potential ecological risk. Monensin was the most toxic among the three drugs tested, and its higher a ffinity to soil made it easier to be accumulated. The potential environmental impacts identified by the drugs tested as a result of their mobility, persistence and ecotoxicity will help to inform veterinary drug managemen<sup>t</sup> and drug residue pollution concerns.

**Author Contributions:** Investigation, P.L. and Y.W. (Yizhao Wu); formal analysis, P.L., Y.W. (Yizhao Wu) and Y.W. (Yali Wang); writing-original draft, P.L. and Y.W. (Yizhao Wu); writing-review & editing, P.L., Y.W. (Yali Wang) and Y.L.; supervision, J.Q. and Y.L.; project administration, Y.L.; funding acquisition, Y.L.

**Funding:** This work was supported by the National key R&D program of China (2017YFD0501405).

**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.
