Chen Hao¹, Bin Gao², and Lena Q Ma¹

¹ Soil and Water Science, University of Florida, Gainesville, FL 32611

² Agricultural and Biological Engineering, University of Florida, Gainesville, FL 32611

* Corresponding author, lqma@ufl.edu, bg55@ufl.edu

Ciprofloxacin (CIP), an emerging contaminant of antibiotics, has been frequently detected in soils and water; however, their fate and transport in soil and groundwater systems remain largely unknown. This study examined CIP transport in saturated porous media under the influence of two divalent cations (Cu²⁺ and Ca²⁺) and two sand media (natural sand and acid-washed sand). Laboratory columns packed with quartz sand were used to determine the effects of co-existence of the two cations on CIP retention and transport. In general, in cation-free solution Cip manifested a much higher mobility in saturated column packed with acid-washed sand. Divalent cations Ca and Cu had different influence on CIP transport in natural sand media. The presence of Cu significantly enhanced the mobility of CIP transport in the sand column whereas Ca had limited impact. Our results indicate that both solution chemistry and porous medium surface property affected the fate and transport of ciprofloxacin in saturated porous media.