Toxicity assessment of four pharmaceuticals in aquatic environment before and after ferrate(VI) treatment

Micro-pollutants in aquatic environment are an emerging challenge to the human health and ecosystems. This study was to investigate the acute toxicity before and after ferrate(VI) treatment for four pharmaceuticals (simvastatin, ivermectin, fluoxetine and oxytetracycline) at concentrations of 10 and 100 μg/L, respectively. Zebrafish animal model and Vibrio fischeri luminescent test were employed to achieve the study targets. It is the first effort using the stated methods to assess toxicity of the selected pharmaceuticals before and after ferrate(VI) treatment when biochemical responses of catalase (CAT), tumour necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1β) and B-cell lymphoma 2 (Bcl-2) were assessed in the zebrafish model. The results firstly revealed a significant change in the gene expression of CAT (p < 0.001), TNF-α SOD 1 (p < 0.01), and Bcl-2 (p < 0.05) for simvastatin at low concentrations, which exhibited high toxicity in comparison with other pharmaceuticals. Ferrate(VI) treatment significantly reduced the toxicity of simvastatin by partially removing it during the treatment process and ferrate(VI) itself did not produce additional toxicity in the effluent.