Comparison of three rapid toxicity test procedures: Microtox,® polytox,® and activated sludge respiration inhibition

Abstract

Methods for measuring respiratory activity can detect adverse effects on heterotrophic microorganisms. These methods are useful tools for assessing the impact of chemicals on biological wastewater treatment processes. They are also well suited for evaluating the treatability potential of individual wastes. However, varying results are oRen reported when using municipal or industrial activated sludge substrate in toxicity assessments. The lack of reproducibility of these tests has also greatly limited efforts to measure the effectiveness of treatment plants in removing toxic contaminants. The toxicity of wastewaters and chemicals to biological treatment systems can be determined in 30 min with the new Polytox@ toxicity procedure. The Polytox@ kit utilizes a specialized blend of bacterial cultures. The objective of this paper is to evaluate the relative sensitivity of the new PolytoxQ toxicity procedure with two accepted microbial assay procedures; namely, the MicrotoxQ bioluminescence assay and the Organization for Economic Cooperation and Development's Activated Sludge Respiration Inhibition test. This paper compares toxicity values for selected inorganic and organic chemicals as determined in the three microbial assay systems. The sensitivity and reliability of the new PolytoxQ toxicity procedure is discussed.

The Toxicity of Substituted Phenolic Compounds to a Detoxifying and an Acetic Acid Bacterium

“…The estimation of respiratory activities has been used primarily to assess the toxicity of chemicals to bacteria (King and Dutka, 1986;Elnabarawy et al, 1988;Strotmann et al, 1993;De Wever et al, 1994;Strotmann and Egläser, 1995;Riis et al, 1996). The reason for this approach might be the fact that measurements are quick and easy to carry out.…”

Assessment of toxicity and biodegradability on activated sludge of priority and emerging pollutants

“…[12] Respirometric measurements are commonly used to determine the effects of toxicants on the activated sludge. [3,[13][14][15][16] Although the respiration rate can be quantified by different methods, the oxygen uptake inhibition rate [14,17] is most frequently used to evaluate the toxicity. [2,6,13] A test using activated sludge for toxicity assessment will not indicate total toxicity since the bacterial density and diversity is high and only the inhibition of the most abundant organisms which are growing faster under the tests conditions is indicated.…”

Development of ecotoxicity assay based on inhibition of respiring activity in microbial community using XTT reduction

“…EC 50 values obtained from the ASRI test and Microtox were compared with those from Elnabarawy et al (1988). These results are indicated in XTT reduction activity is increased by the presence of cytochrome oxidase inhibitors such as cyanide and sodium azide (Kunimoto et al, 1999;Roslev and King, 1993).…”