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Textile wastewater was treated with sludge flocs and aerobic granules (AGS) in SBR.
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Higher anaerobic and overall COD removal yields were observed in the AGS SBR.
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High azo dye decolorization was attained with both flocs and aerobic granules.
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Decolorization products showed higher cyto- and genotoxic potential than original dye.
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AGS had better performance in decolorization product detoxification potential