Chemicals as useful they are, can be harmful to humans and the environment. Therefore it appears rather clear that only those chemicals should be used in the markets that do not have an adverse impact on humans and the environment. The list of chemicals being in the market of the European Union between 1971 and 1981 (EINECS list, http://chemicalwatch.com/927) contains 100000 chemicals and almost 1000 chemicals newly enter the market, yearly, see e.g. Bruggemann & Drescher-Kaden (2003), van Leeuwen et al. (1996) and Ahlers (1999). How do we find out whether they are hazardous? There are many time-consuming and expensive investigations necessary to perform a risk assessment. Hence the question is: with which chemicals to begin at first? Thus ranking is needed to give the more involved investigations a reasonable operating sequence, Newman (1995).