| Pharmaceutical and personal care products (PPCPs) and their active metabolites are an emerging environmental issue, due to their presence in the aquatic environment and potential impacts on wildlife and humans. Coagulation, sedimentation, filtration and other conventional water treatment technology can not remove these toxic substances effectively. It is a simple and inexpensive solution that biological pretreatment of raw water to reduce PPCPs. Currently, the removal of PPCPs in micro-polluted source water by combination of bioaugmentation technology and biological aerated filter technology (BAF) has not been reported. To provide technical support, the bacteria capable of degrading selected PPCPs were isolated.and applied into BAF in this study.The selected PPCPs were Bezafibrate (BZF), Carbamazepine (CBZ) and lbuprofen (IBU). Strain B31, DHU-33 and BL-1, which could degrade the selected PPCPs by cometabolism respectively, were isolated from activated sludge of sewage treatment plant in Shanghai. Based on its morphology, physiology and phylogenetic analysis of 16S rRNA sequence, they were identified as Pseudomonas putida, Alcaligenes sp. and Serratia marcescens. The optimum initial degrading selected PPCPs condition of each was at 30℃, pH 7.Strain B-31 could degrade BZF by 48% in liquid mineral salt medium with 30 mg/L BZF and 1% methanol in 5 days. Strain DHU-33 could degrade CBZ by 34% in liquid mineral salt medium with 25 mg/L CBZ and 1% methanol in 5 days. Strain BL-1 could degrade IBU by 75% in liquid mineral salt medium with 30 mg/L IBU and 1% methanol in 5 days. Compared with methanol, yeast extract, peptone and glucose could significantly enhance the degradation rate of selected PPCPs. The highest degradation rate was 76.67%, 54.4% and 94.3% respectively when 5 g/L yeast extract was added.The relationship between glucose consumption and the degradation of PPCPs was studied. In general, the degradation of PPCPs was correlated with glucose consumption positively. The degradation process of CBZ, IBU and glucose close to first-order kinetics, except for the degradation process of BZF close to zero-order kinetics.When methanol was the primary substrate,7 kinds of degradation products of BZF were detected by GC-MS.4-chlorobenzoate was the mainly degradation product. According to analysis of degradation products, BZF degradation process involves amide bond hydrolysis, oxidation of primary amine groups, benzene and double hydroxylation. There were 4 kinds of degradation products of CBZ, including CBZ-EP (1aH-dibenzo [b, f] oxireno[2,3-d]azepine-6(10bH)-carboxamide),CBZ-DiOH(10R,11S)-10,11-dihydroxy-10,11-dihydro-5H-dibenzo [b, f] azepine-5-carboxamide),2-hydroxy benzoic acid and o-amino benzoic acid. The mainly degradation products of IBU was 2-(4-acetyl-phenyl) propionic acid. And a red pigment was found in the degradation process of IBU.The mixture of PPCPs degradation bacteria and activated sludge were added to bio-ceramic BAF and high effective fiber ball BAF to formatting biofilm. And only activated sludge was added as control. The removal of CODMn and NH3-N were detected. Biological phase was also analyzed. The results show that the PPCPs degradation bacteria were not accelerated the biofilm formation significantly.When the influent was 15.6℃-24.5℃,pH 6.88-7.27, the removal of CODMn and NH3-N were increased with the hydraulic loading, and decreased with gas-water ratio. When the influent load was 0.2 m3/m2·h and gas water ratio was 1.5:1, the BAF added with PPCPs degradation bacteria had some slight advantage in removing CODMnand NH3-N. Compared with the control, the removal of CODMn increased 1.17% and 1.44%, and the removal of NH3-N increased 0.60% and 1.56%.Whether adding PPCPs degradation bacteria or not, the removal of selected PPCPs were decreased with the hydraulic loading and gas-water ratio. However, the bio-ceramic filler is better than high effective fiber ball filter. When the influent load was 0.2 m3/m2·h and gas'water ratio was 1.5:1, the BAF added with PPCPs degradation bacteria had a great advantage in removing selected PPCPs on short-term. Compared with the control, the removal rate of PPCPs has improved significantly. Especially the bio-ceramic BAF added with PPCPs degradation bacteria had a better performance than the other BAF. Its CBZ, IBU and BZF removal rate was 46.55%,93.03% and 96.97% respectively.
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