Solar−Driven Antibiotic Ciprofloxacin Elimination by Bi₄Ti₃O₁₂ and Biotoxicity Evaluation of Degradation Process on Aquatic Organisms and Bean Seedling

ABSTRACT: Photocatalytic degradation of antibiotic molecules has great significance in environmental pollution control. Bi₄Ti₃O₁₂ with a layered structure is one of the emerging visible−light−responsive photocatalysts. However, the environmental effects of antibiotic degradation have not received sufficient attention. This study employed plate−like Bi₄Ti₃O₁₂ derived from Na₂Ti₃O₇ nanowires for ciprofloxacin (CIP) degradation, and investigated the biotoxicity of degradation products on aquatic organisms and plant seedlings. It was found that an appropriate hydrothermal treatment time with ethylene glycol could slightly enhance the photocatalytic performance of Bi₄Ti₃O₁₂, and this might be attributed to the increased density of active sites resulting from the regulation of microstructure. Concurrently, the degradation products of CIP were detected and predicted for biotoxicity; the effects of the CIP degradation residual solution on the growth of peas, wheat, and zebrafish larvae were also investigated. Under the present experimental conditions, the Bi₄Ti₃O₁₂−24h photocatalyst−involved CIP degradation process could reduce the biotoxicity of the CIP solution (40 mg/L) and exhibit low toxicity to several individual organisms, including some actual plants and animals.