Introduction
Textile waste waters are rated among the most polluting of all industrial sectors, both in terms of discharged volumes and com-position, but their most important environmental problems arise from the high organic loads and the presence of color [1].
Azodyes are the most common synthetic colorants released in textile waste waters [2] due to their ease of synthesis, stability and vari-ety of colors.
Due to the electron-withdrawing nature of azo bonds,azo dyes are easily reduced by bacteria under anaerobic conditions,resulting in color removal with the formation of aromatic amines[3].
Key data on the health hazard associated with the majority ofthese aromatic amines are limited [4], but some of these azo dyebreakdown products have been considered of higher concern thanthe original dye with respect to their possible (eco) toxicity and/ormutagenicity/carcinogenicity [5,6].