The toxicity of textile reactive azo dyes after hydrolysis and decolourisation.
The toxicity of C.I. Reactive Black 5 and three Procion dyes, as found in textile effluents, was determined using the bioluminescent bacterium Vibrio fischeri. Hydrolysed Reactive Black had a slightly greater toxicity than the parent form (EC(50) 11.4+/-3.68 and 27.5+/-4.01 mg l(-1), respectively). A baffled bioreactor with anaerobic and aerobic compartments was used to decolourise hydrolysed Reactive Black 5 in a synthetic effluent. Decolourisation of hydrolysed Reactive Black resulted in an increased toxicity (EC(50) 0.2+/-0.03 mg l(-1)). Toxicity was not detectable when decolourised Reactive Black 5 was metabolised under aerobic conditions. No genotoxicity was detected after the decolourisation of either the parent or the hydrolysed reactive dyes, either in vitro or in the bioreactor. The toxicity and genotoxicity of decolourised C.I. Acid Orange 7 was due to the production of 1-amino-2-naphthol (EC(50) 0.1+/-0.03 mg l(-1)).
Gottlieb
Anna
A
Department of Life Sciences, The Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, UK.
Shaw
Chris
C
Smith
Alan
A
Wheatley
Andrew
A
Forsythe
Stephen
S
D000693:Anaerobiosis; D001391:Azo Compounds / Q000378:metabolism* / Q000633:toxicity*; D001673:Biodegradation, Environmental; D019149:Bioreactors; D002478:Cells, Cultured; D003013:Clostridium / Q000378:metabolism*; D018920:Coculture Techniques; D003116:Color; D004396:Coloring Agents / Q000378:metabolism / Q000633:toxicity; D013293:Enterococcus faecalis / Q000378:metabolism*; D006868:Hydrolysis; D007220:Industrial Waste / Q000009:adverse effects; D007928:Lethal Dose 50; D009152:Mutagenicity Tests; D009282:Naphthalenesulfonates; D013045:Species Specificity; D013784:Textiles / Q000633:toxicity*; D014227:Triazines; D014733:Vibrio / Q000145:classification / Q000187:drug effects*; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000633:toxicity; D018508:Water Purification / Q000379:methods
D001391:Azo Compounds; D004396:Coloring Agents; D007220:Industrial Waste; D009282:Naphthalenesulfonates; D014227:Triazines; D014874:Water Pollutants, Chemical; C090144:Procion navy MX-RB; C009794:procion yellow; C063421:Remazol black B