HC-BioSIM

The Hydrocarbon Biodegradation System-integrated Model (HC-BioSIM) is a quantitative structure property relationship (QSPR) model for estimating the degradation half-life (DT50) of petroleum hydrocarbons under varying test system and environmental conditions. The model was developed by ExxonMobil Biomedical Sciences, Inc. in 2022 and is published with open-access in Environmental Toxicology & Chemistry (DOI: https://doi.org/10.1002/etc.5328). The model uses a cubist decision tree algorithm (Quinlan, 1995) along with user-defined inputs of key system parameters (Temperature, Loading, Test Material Viscosity, Dispersant Treat Rate, and Aquatic Test System) and existing ToxPrint chemical structure fragments derived from the ChemoTyper software (v1.0). The model was developed to provide environmentally-relevant estimates of hydrocarbon biodegradation half-lives across a variety of real-world environmental scenarios – the output of which may be used for chemical hazard assessment (i.e. PBT or PMT assessment), quantitative risk assessment, oil spill response, water quality modeling applications, etc. A full description of the model, its training set, and its performance are provided in the original publication. Integration for OECD Toolbox including QMRF documentation of the model, its applicability domain, performance, and output has been developed by OASIS LMC. The model is made available for use through the OECD QSAR Toolbox with support and funding from CONCAWE (www.concawe.eu) and ExxonMobil.