Physico-chemical Data Estimation for Environmental Chemicals

The environmental fate and mobility assessment is an essential part of the process of selecting and identifying environmental chemicals. However, for most chemicals only fragmentary knowledge exists about those properties which determine their fate in the environment. Therefore, it is pertinent to estimate these physical-chemical data on chemicals. Due to the huge number of organics not only an appropriate package of formula but also a high degree of automatism for this task is needed.There are two types of approaches to estimate properties. The first one is to use a databasis for fragments of the molecule. The second one is to use property-property- relationships which in general do not need the knowledge of (sub)structures.Therefore, DTEST which is part of the EDP-code E4CHEM (acronym for “Exposure and Ecotoxicity Estimation for Environmental Chemicals”) mainly property-property- relationships are used which allow a high degree of automatism. The relationship to calculate vapor pressure, partition coefficients, solubility and other environmental relevant properties are shown and discussed in DTEST. A brief explanation of the leading ideas in the program structure is given.