Petroleum kerosene fraction, co-processed with renewable hydrocarbons of plant and/or animal origin

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Substance is a hydrocarbon UVCB. Tests for biodegradation in water are designed for use with single chemical substances and results used for classification. For the purpose of risk assessment, this endpoint is characterized using quantitative structure property relationships for representative hydrocarbon structures that comprise the hydrocarbon blocks. The environmental risk of this substance is assessed using the PETRORISK model (see Product Library in PETRORISK spreadsheet attached to IUCLID Section 13).

Kerosine fractions are not readily biodegradable but are considered inherently biodegradable. In a report on environmental classification (Concawe 2001), it was concluded that, based on the known properties of hydrocarbons in the range C9 to C16,kerosines are not readily biodegradable, but are regarded as being inherently biodegradable, since they can be degraded by micro-organisms. In a further investigation (Concawe 2012) on PBT evaluation of petroleum substances CONCAWE developed QSAR estimates (BioHCwin) and reviewed existing data for individual hydrocarbons representative of the various ‘hydrocarbon blocks’ covering a range of petroleum substances. Using the Hydrocarbon Block method and data on biodegradation of representative hydrocarbons in the range C9 to C20, it is concluded that kerosines do not meet the persistence criteria and can be regarded as being inherently biodegradable.

The material is a complex hydrocarbon UVCB and standard methods for assessing bioaccumulation are not appropriate. However, bioccumulation potential has been calculated for representative hydrocarbon structures using the BCFWIN v2.16 model within EPISuite 3.12 as input to the hydrocarbon block method incorporated into the PETRORISK model. The predicted BCFs for hydrocarbons are generally overly conservative since biotransformation is not quantitatively taken into account. Therefore, indirect exposure and resulting risk estimates predicted by PETRORISK are likely to be overestimated. For the purposes of PBT assessment, measured bioaccumulation data for representative hydrocarbon constituents have been used as detailed in section 8 of the CSR.

The toxicity component has been assessed on the following basis. Aquatic toxicity was estimated using the PETROTOX computer model, which combines a partitioning model (used to calculate the aqueous concentration of hydrocarbon components as a function of substance loading) with the Target Lipid Model (used to calculate acute and chronic toxicity of non-polar narcotic chemicals). PETROTOX computes toxicity based on the summation of the aqueous-phase concentrations of hydrocarbon block(s) that represent a petroleum substance and membrane-water partition coefficients (Kmw) that describe the partitioning of the hydrocarbons between the water and organism. The estimated freshwater fish NOEL (No Observed Effect Level) value is 0.34 mg/L based on mortality. Further, the material is not classified for CMR or STOT (repeat) properties.