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Ecotoxicological information

Toxicity to aquatic plants other than algae

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Description of key information

LAS provides suitable read across for LAB Sulfonic Acids as both form the identical chemical species in aqueous solutions at environmental pH’s, namely, the LAS ion (C10-13 linear alkyl benzene-SO3-).

Two aquatic plant (other than algae) studies were conducted. In the first study (Maki 1981), the long term toxicity of C11.6LAS to the aquatic plant (Elodea canadensis) was determined in a 28 day model ecosystem test. The nominal test concentrations were 0.5, 1.0, 2.0, and 4.0 mg/L, and were confirmed by analytical measurements.Growth inhibition was not observed even at highest tested concentration (4 mg/L). Growth throughout the exposure period approximately doubled the initial biomass of the vegetative shoots used at the start of the exposure. Hence, the NOEC was found to be >4 mg/L. The data are for C11.6 LAS and no normalization is required.

In the second study (Bishop and Perry 1981; Bishop 1980; van de Plassche et al 1999), the duckweed, Lemna minor, was exposed to C11.8LAS. Endpoints included frond count, dry weight, growth rate, and root length after a 7 day exposure period in a flow through study. The measured test concentrations were 0, 2.1, 3.8, 8, 17 and 34 mg/L. The resultant EC10 value, based on frond number, was 0.21 mg/L. The EC50 value, also based on frond number, was 2.30 mg/L C11.8LAS. Normalizing the EC10 of 0.21 mg/L to C11.6LAS results in a final value of 0.30 mg/L.

Key value for chemical safety assessment

EC50 for freshwater plants:
2.3 mg/L
EC10 or NOEC for freshwater plants:
0.268 mg/L

Additional information