Multimedia mass balance approach to characterizing the transport potential of antibiotics in soil–plant systems following manure application

Abstract

Antibiotics are ubiquitous in agro-ecosystems worldwide, which can pose remarkable risks to ecological security and human health. However, comprehensive evaluation on the multimedia fate and transport potential of antibiotics in soil–plant systems is still lacking. A mass balance approach was performed to gain insights into the transport and fate of antibiotics in soil–plant systems following manure application. Our results showed that more than 99 % of antibiotics were released from applied manure fertilizer into the soil–plant system. Antibiotic concentrations in soil and plant compartments increased over 120 days. Most of the antibiotics persisted in soil (about 65 %), while less than 0.1 % accumulated in the plants. Rainfall-induced runoff, subsurface interflow and soil water infiltration were alternative transport pathways for antibiotics in soil–plant systems although their contributions were limited. Dissipation was the main removal pathway for antibiotics accounting for about 33 % of total input mass. Tetracyclines had higher mass proportion in soil following by quinolones, whereas most of sulfonamides and macrolides were dissipated. Mass balance approach based on tracking environmental fates of antibiotics can facilitate the understandings in the source comparisons and mitigation strategies, and therefore provide insights to inform modeling and limiting the transport of manure-borne antibiotics to neighboring environmental compartments.