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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

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Ecotoxicological information

Toxicity to microorganisms

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Administrative data

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Description of key information

Experimental data are available for the toxicity of some Category B constituents towards active sludge. The 28 day NOEC for Hydrocarbons, C4, 1,3-butadiene-free, polymd., dibutylene fraction was 100 mg/L based on nominal concentrations. The 56 day NOEC for Hydrocarbons, C4, 1,3-butadiene-free, polymd., tetraisobutylene fraction, hydrogenated was 23.5 mg/L based on nominal concentrations.


In addition to the experimental data, the aquatic toxicity for the main Category B constituents (C8, C12, C16 and C20 iso-olefins) was predicted by a QSAR, the PETROTOX v4.0 computer model. PETROTOX is a well-documented and peer reviewed model that is widely used across the chemicals industry. The predicted LL50 values for Activated Sludge ranged from >1000 to >1000 mg/L. The predicted EL10 values for Activated Sludge ranged from 6.23 to >1000 mg/L.

Key value for chemical safety assessment

Additional information

The PETROTOX v4.0 model combines a partitioning model used to calculate the aqueous concentration of hydrocarbon constituents 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 hydrocarbon substance and membrane-water partition coefficients (KMW) that describe the partitioning of the hydrocarbons between the water and organism.


The predicted values were:

Species Carbon No. LL50 / EL50 (mg/L) EL10 (mg/L)
Activated Sludge C8 >1000 6.23
Activated Sludge C12 >1000 >1000
Activated Sludge C16 >1000 >1000
Activated Sludge C20 >1000 >1000