Effect directed analysis

Effect-Directed Analysis of Complex Environmental Contamination... 

Brack W. 2003. Effect-directed analysis a promising tool for the identification of organic toxicants in complex mixtures Ann Bioanal Chem 377 397-407. 

Grote M, Brack W, Walter H, Altenburger R. 2005. Confirmation of cause-effect relationships in effect-directed analysis of complex contaminated samples. Environ Toxicol Chem 24 1420-1427. 

Whole mixture approaches may also be indicated as diagnosis instruments, and are often used for site-specific, retrospective investigations, and hence often deal with complex mixtures, that is, those that have at least partly an unknown chemical composition. This may, for example, concern industrial or field samples containing a mixture of chemicals that is only partly or incompletely characterized. Whole mixture approaches may include bioassays, effect-directed analysis (EDA), and toxicity identification evaluation (TIE). Bioassays may be used to determine actual toxicity of an environmental sample, and do not necessarily bother about composition of the mixture or toxicity of the components. EDA and TIE approaches may be used to identify the (groups of) chemicals that are the main cause of toxicity. Mixture toxicity concepts may be useful to explain how chemicals present in the sample could have interacted to cause its toxicity. 

Application of the effect-directed analysis methodology has been reviewed. It consists of the search of toxic compounds present in complex samples, such as those stemming from the environment and industrial effluents, following the simplification operations shown in equation 4, where BA = biological assay, CA = chemical analysis and FR = fractionation. At present it is too expensive for screening applications however, it is amply justified for identification of specific toxicants near the source of emission, as was the case of mutagens in Table 2.D in river waters84. 

W. Brack, M. Schmitt-Jansen, M. Machala, R. Brix, D. Barcelo, E. Schymanski, G. Streck, and T. Schulze. Flow to confirm identified toxicants in effect-directed analysis. Anal. Bioanal. Chem., 390 1959-1973,2008. 

C. Meinert, E. Schymanski, E. Kiister, R. Kiihne, G. Schiiiirmann, and W. Brack. Application of preparative capillary gas chromatography (pcGC), automated structure generation and mutagenicity prediction to improve effect-directed analysis of genotoxicants in a contaminated groundwater. Environ. Sci. Pollut. Res., 17(4) 885-897, 2010. 

G. Streck, and W. Brack. Identification of a photo-transformation product of diclofenac using effect-directed analysis. Environ. Pollut, 158(5) 1461-1466, 2010. 

E. Schymanski. Integrated Analytical and Computer Tools for Toxicant Identification in Effect-Directed Analysis. Doctoral Thesis, Faculty for Chemistry and Physics, Technical University Bergakadamie Freiberg, Freiberg, Germany, 2011. 

E. Schymanski, C. Meinert, M. Meringer, and W. Brack. The use of MS classifiers and structure generation to assist in the identification of unknowns in effect-directed analysis. Anal. Chim. Acta, 615 136-147, 2008. 

Finally, E. Schymanski used several MOLGEN products during her dissertation [283] at the Helmholtz Centre for Environmental Research (UFZ, Leipzig, Germany) to integrate analytical and computational methods to identify unknown toxicants isoiated during effect-directed analysis. 

Morlock, G., Schwack, W. (2009) Effect-directed analysis by planar chromatography. Journal of Chromatography. A, 1217, 6600-6609. 

M. G. Weller, A unifying review of bioassay-guided fractionation, effect-directed analysis and related techniques. Sensors 12 9181-9209, 2012. 

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