Microtox and Mutatox

Sample type Microtox toxicity ECso Mutatox genotoxicity 

Microtox responds well to a wide array of hydrophobic chemicals (see the work of Johnson [1998] in which a variety of pesticides, industrial chemicals and petroleum products were tested). Apparently, Microtox is highly responsive to compounds with a narcosis mode of toxicity (Johnson, 1998 Sabaliunas et al., 1998). As shown by Johnson (1998) chemicals that elicit narcosis include multiple chemical classes. 

EROD activity is measured in the H411E cells as follows. The cells are seeded at 7,000 cells per well in 250 xL of Dulbecco s modified Eagles culture media (Tillitt et al., 1991). After an initial incubation period of 24 hours, the cells are dosed with 5 xL volumes of eiuiched SPMD extracts (cleanup of extracts generally includes dialysis and size exclusion chromatography [SEC]) and incubated for an additional 72 hours. Sample dose is typically expressed as g-equivalents triolein or whole SPMD per mg cellular protein. Multiple exposures are performed at each of six (typically) sample concentrations, using a dilution series. Afterwards, the microtiter plates are washed three times with distilled water to lyse the cells. EROD activity (pmol mg cellular protein per min) in each sample is measured 

Eigure 6.2, shows a specific example of the use of the H4IIE-EROD assay for purified SPMD extracts. After purification of SPMD extracts. Gale et al. (2000) showed that H4IIE-determined TEQs were well correlated with instrumentally-determined TEQs. 

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Table 6.2 Use of Microtox and Mutatox to Determine the Toxicity of SPMD Concentrates. Reprinted with permission from the American Petroleum Institute (Huckins et al., 2002)...

Freshly prepared blank SPMD, carried through Microtox and Mutatox test. 

Both the Microtox and Mutatox w techniques provide results indicating the usefulness of luminescent bacterial assays which are simple, fast and are comparatively inexpensive alternatives to both chemical techniques and to in vivo bioassays with higher organisms. 

Toxicity in estuarine sediments—use of Mutatox and Microtox to evalu- 173 ate the acute toxicity and genotoxicity of organic sediments Toxicity tests for the analysis of pore water sediment a comparison of 4 174... 

Cleveland, L. Little, E.E. Petty, J.D. Johnson, B.T. Lebo, J.A. Orazio, C.E. Dionne. J. Crockett, A. 1997, Toxicological and chemical screening of Antarctica sediments Use of whole sediment toxicity tests, Microtox, Mutatox, and semipermeable membrane devices (SPMDs). Mar. Pollut. Bull 34 194-202. 

The bacterial Microtox tests and the other in vitro bioassays clearly indicated differences in sediment toxicity between locations (Table 7). In the Microtox SP assay inhibitory effects were found in sediment extracts from the Port of Amsterdam transect (i.e. TU values greater than 20 at sites 7 and 11). The highest response in the Mutatox assay was found at Oranjesluis (site 11) in the Port of Amsterdam. The reference values from the Mutatox assay at this site were below... 

Eggens M., Schipper C., Vethaak A. and Klamer H., Mutatox and Microtox assays in a pollution gradient along the Dutch coastal zone. International Symposium on New Microbiotests, 1998, Brno, Czech Republic s. ... 

Hauser, B., Schrader, G. and Bahadir, M. (1997) Comparison of acute toxicity and genotoxic concentrations of single compounds and waste elutriates using the Microtox/Mutatox test system, Ecotoxicology and Environmental Safety 38 (3), 227-231. 

Among the two genotoxicity tests, the Mutatox is a commercial test using a bacterial strain and is no more difficult to perform than the well known Microtox test. The test on induction of micronuclei in erythrocytes of Xenopus laevis larvae developed by van Hummelen et al. (1989) requires specialized skills and training and is routinely performed only in a few laboratories. However, this test is currently being standardized by ISO (International Standardization Organisation). 

Table 4.4 River surface water toxicology data with point scores and ranking (Dutka et al.. 1991). Site and D. S. Toxi Microtox ATP-TOX Algal C. Mutatox Total...

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