ConGENER – A Tool for Modeling of the Congeneric Sets of Environmental Pollutants

Congeners are molecules based on the same carbon skeleton but different by a substitution pattern, e.g., 1-chloronaphthalene, 1,4-dichloronaphthalene, 1,3,8-trichloronaphthalene, etc. Various Persistent Organic Pollutants (POPs) exist in the environment as families of halogen-substituted congeners. To facilitate computational studies on these species we developed ConGENER software package. The main program combinatorially generates all congeners of a parent molecule. The generated structures can be easily imported into quantum chemistry programs with scripting programs included in the package. Other included scripts can analyze outputs from the following quantum-mechanical calculations and provide tabularized results easily imported into QSAR/QSPR programs to perform environmental toxicity studies. We demonstrate the application of ConGENER to study congeneric family of 287 chloropyrenes. This study explains how the individual molecular properties are changing according to a substitution pattern. In addition, we identified a new research need for validation of PM6 method in the case of perchlorinated congeners of PAHs.