A Chemical Properties Simulator to Support IEM

Session F5: Advances in Environmental Software Systems

Users of Integrated Environmental Modeling (IEM) systems are responsible for defining individual chemicals and their properties, a process that is time-consuming at best and overwhelming at worst, especially for new chemicals with new structures. A software tool is needed to allow users to define a chemical structure, predict transformation products within an environmental setting, and calculate relevant physicochemical properties. Independent software provides relevant chemical and environmental descriptors to parameterize IEM systems that support fate/transport of organics by integrating cheminformatic applications and software technologies. These 1) encode process science using SMART reaction strings, an extension of SMILES notation; 2) generate transformation products based on functional group analysis (nitroaromatics, azo aromatics, halogenated alkanes), environmental conditions (aerobic or anaerobic), and reaction processes (reduction, hydrolysis, photolysis, biodegradation); 3) generate molecular descriptors (partition coefficients, electron affinities) through calculators; 4) collect environmental descriptors (pH, Fe(II), dissolved organic carbon, soil organic carbon content) from a user or via web-based databases (National Water Quality Database); and 5) retrieve and analyze generated data (quantitative structure activity relationships) in structure-based databases. The results are a web-based tool where the user identifies the organic chemical by structure, common or IUPAC name, or CASID; selects reaction conditions and media; provides environmental descriptors from site-specific data; and chooses a specific transformation process from a reaction library to produce transformation pathways and products, with their physicochemical properties, for IEM consumption.