Concawe has developed PETROTOX, a spreadsheet model, designed to calculate the toxicity of petroleum products to aquatic organisms.

Petroleum hydrocarbons are complex mixtures that exert a narcotic mode of toxic action, which is assumed to be additive. This model calculates the solubility of a petroleum product and then uses the Target Lipid Model (TLM) (Di Toro et al. 2000) and toxic unit theory of additivity to calculate the toxicity or environmental risk limits of these mixtures.

The spreadsheet uses a three-phase (air, water, free product) oil solubility calculation (McGrath et al. 2004) that is coupled with a database of physical and chemical properties of typical petroleum hydrocarbons to calculate the distribution of petroleum hydrocarbons among the exposure water, headspace and free product phases. The properties database was developed by Concawe and contains physical/chemical properties such as boiling point, solubility and octanol-water partition coefficients (Kow) for 1462 hydrocarbon structures that are possibly found in petroleum products. This version of the Petrotox model performs the solubility and toxicity calculations with physiochemical properties derived from the database for each hydrocarbon block.

A variation of the model, PETROTOX-UDM allows the user to define the physio-chemical properties of the hydrocarbon blocks instead of relying on the representative library structures from CONCAWE’s hydrocarbon database. This version has many of the same features as the library-based version and can be utilized for the same types of applications. The user is required to input log(KOW), solubility, Henry’s Law Constants, molecular weight (MW) and chemical class for each hydrocarbon block.

These spreadsheet models can be used to analyze dose response data, calculate LL50s, or toxic units for user-input dose response data as a means of analyzing and designing toxicity experiments. The models can be used to analyze the results of fate models to calculate environmental toxicity and potential risk of hydrocarbon emissions in aquatic compartments. The environmental toxicity of individual hydrocarbons or specific hydrocarbon blocks can also be evaluated using the user-defined spreadsheet model.

Before downloading the Petrotox files, we require you to register so that we have your e-mail address and can notify you of any updates when these become available.