1,2,4-trimethylbenzene

Toxicity to aquatic algae and cyanobacteria

Description of key information

QSAR calculation gives an estimates 96hr EC50 for algae of 2.356 mg/l.

Key value for chemical safety assessment

EC50 for freshwater algae:

2.356 mg/L

Additional information

A standard algal toxicity test is not available for 1, 2, 4-trimethylbenzene. In the absence of measured data the use of a QSAR to predict the ecotoxicity of 1, 2, 4-trimethylbenzene is an appropriate technique to use when assessing whether this substance would meet the criteria for PBT and potential classification. The ECOSAR model is a reliable and appropriate QSAR model to apply to 1, 2, 4-trimethylbenzene as it is based on a related chemical dataset that calculates the toxicity of neutral organic hydrocarbons whose mode of action is non-polar narcosis. The endpoint calculated here is therefore a reasonable estimate of its baseline toxicity. The result does not indicate that 1,2,4-trimethylbenzene would meet the criteria for toxic in the PBT assessment. This endpoint would not affect the classification of the 1, 2, 4-trimethylbenzene since the substance is biodegradable and the log Kow is < 4.0.