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(T/MF153) Temperature dependent compound properties in environmental fate modeling. Kühne, Ralph1, Ebert, Ralf-Uwe1, Schüürmann, Gerrit1, 1 ABSTRACT- Environmental fate models utilize some key compound properties to estimate the fate of individual chemicals, namely partitioning properties and degradation rates. A large number of experimental data as well as estimation methods are available in order to provide the necessary values. All of these compound properties to a greater or lesser extent depend on temperature. Unfortunately, estimation methods in most cases are focussed on 25° C, which is not very realistic in terms of European ambient temperatures. Experimental data occasionally are available for several temperatures, but not necessarily for the temperatures of interest. As a consequence, data at 25°C are applied regularly. This study demonstrates the importance of the consideration of temperature dependency of Henry's law constant and vapour pressure in environmental fate modelling. In a steady-state fugacity model, the influence of the temperature dependency on the estimation of partitioning ratios, persistence in compartments, and long-range transport potential is analysed, and it is compared with the influence of other essential model parameters as compartment sizes and water content. To obtain representative results, the calculations are performed for a set of several hundreds organic compounds, covering a wide range of compound classes. Key words: fugacity model, compound property, temperature dependency |
