Clear and present danger? The use of a yeast biosensor to monitor changes in the toxicity of industrial effluents subjected to oxidative colour removal treatments.
Discharges of coloured effluents into surface waters provide conspicuous evidence of the impact of industry on the environment. The textile industry is an obvious candidate for sources of such discharges. Conventional treatment methods appear to alleviate this situation by removing colour, however the affect on toxicity is less obvious. The objective of this study was to examine the changes in effluent toxicity during the course of two alternative wastewater treatment methods, ozonation and electrochemical oxidation, using a novel toxicity biosensor, GreenScreen EM. The biosensor is capable of measuring both general acute toxicity (cytotoxicity), and more specifically genotoxicity, that is damage to a cell's DNA structure, replication or distribution, caused by substances that may be mutagenic and/or carcinogenic. The biosensor utilises a modified strain of the brewers yeast Saccharomyces cerevisiae, incorporating a gene encoding green fluorescent protein (GFP) linked to the inducible promoter of the DNA damage responsive RAD54 gene. Upon exposure to a genotoxin, the production of GFP is up-regulated in parallel with RAD54, and the resulting cellular fluorescence provides a measure of genotoxicity. Acute toxicity is simultaneously determined by monitoring relative total growth of the cell culture during incubation. The results presented in this paper show that a reduction in colouration does not necessarily correspond to a reduction in effluent toxicity.
Keenan
Patrick O
PO
Gentronix Limited, CTF Building, 46 Grafton Street, Manchester, UK M13 9NT. p.keenan@lancaster.ac.uk
Knight
Andrew W
AW
Billinton
Nicholas
N
Cahill
Paul A
PA
Dalrymple
Ian M
IM
Hawkyard
Christopher J
CJ
Stratton-Campbell
Duncan
D
Walmsley
Richard M
RM
D015374:Biosensing Techniques; D003116:Color; D007220:Industrial Waste; D009153:Mutagens / Q000633:toxicity*; D016877:Oxidants / Q000737:chemistry; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*; D018508:Water Purification / Q000379:methods
D007220:Industrial Waste; D009153:Mutagens; D016877:Oxidants; D014874:Water Pollutants, Chemical; D010126:Ozone