„Effect characterization for selected compounds and mixtures“
The question whether damage of the genetic material arises from direct or indirect genotoxic effects of an agent and the underlaying mechanisms have gained considerable attention in the context of hazard characterization. This topic has been addressed in in vitro studies with selected chemicals, mycotoxins and their mixtures, also with other agents. Research needs exist also for so-called „endocrine disruptors“: The biological efficacy of estrogenic compounds and combinations has been studied in vitro and in vivo (in cooperation with Prof. Dr. P. Diel, DSHS Köln) and also their kinetics in rodents. In two thesis projects estrogenic effects of cadmium were characterized in a rodent model, and the results are relevant for toxicological evaluations of this heavy metal.
A sensitive method for determining isoflavone phytoestrogens in urine (daidzein, equol and genistein) was validated. The biomonitoring method has been applied within a research project (supported by CEFIC-LRI) to investigate the exposure of German children against phytoestrogens (in cooperation with Prof. Remer, FKE Dortmund). For more information see completed projects & publications. A completed thesis project on the mycotoxin ochratoxin A (OTA) has assessed exposures in breastfed infants from Chile (cooperation with the University of Conception) and from Germany (see publications by K. Munoz). New validated methods for analysis of the structurally related nephrotoxin citrinin (CIT) and its metabolite dihydrocitrinon have been applied to characterize for the first time an exposure to this mycotoxin in adult cohorts from Bangladesh and Germany. A thesis project (Nurshad Ali) investigated by means of biomonitoring also exposure to other important mycotoxins: It revealed significant exposures to aflatoxins in Bangladesh which raise concerns.
„Toxicological risk evaluations“
Research projects on selected hazardous chemicals take up either principal scientific questions with regard to occupational limit value setting for carcinogenic chemicals or are closely related to questions of advisory regulatory bodies (AGS, MAK, SCOEL) on classification and labelling of such compounds. Internationally recognized papers of the project group on matters of risk evaluation for important industrial chemicals such as acrylamide, acrylnitril, ethylene oxide, formaldehyde, trichloroethylene, vinyl acetate and vinylchloride are key elements in new concepts for the regulation of carcinogenic chemicals (see → publications). Work in this field thus accomodates also the aspect of applied research.