Deciphering the role of calcium peroxide on the fate of antibiotic resistance genes and mobile genetic elements during bioelectrochemically-assisted anaerobic composting of excess dewatered sludge

•AnCBE was conducted to investigate the CaO2 addition on the attenuation of ARGs.•The abundances of ARGs in AnCBE at CaO2 dosage of 0.4 and 0.5 g/gVSS were the lowest.•ARGs distribution was affected by both CaO2 and bioelectrochemical assistance.•Microbial community contributed 62.8% to explain the ARGs compositions.•There were positive correlations between sulI, sulII, tetG and blaTEM, and MRGs.