ANTIBIOTICS REMOVAL FROM TREATED SEWAGE USING ZEOLITE AND EVALUATION OF ECOTOXICITY TO GREEN ALGA

Abstract

 This study investigated removal of five types of antibiotics, i.e., roxithromycin (ROX), clarithromycin (CLR), levofloxacin/ofloxacin (LEV), sulfamethoxazole (SMZ), sulfapyridine(SPD), from treated sewage using zeolite. After antibiotic solution was treated for 1 hour, removal ratio was high for ROX and CLR (> 93%), and LEV (> 60%), but low for SMZ and SPD (< 7%). The same trend was observed in antibiotic removal from treated sewage. Ecotoxicity of antibiotics in treated sewage to R. subcapitata was assessed using the total of toxic unit (TU_sum) for each antibiotic. TU_sum of treated sewage contacted with zeolite was much lower than that of treated sewage because zeolite treatment effectively removed CLR which has high TU value. In addition, acute toxic test comfirmed zeolite-treated wastewater had no inhibition effect to R. subcapitata. Meanwhile, since visible humic acid-like-material adsorded on zeolite, it is needed to investigate continuity of effective removal of antibiotics using zeolite.