Sulfuric acid, mono-C12-14 (even numbered)-alkyl esters, compds. with ethanolamine

Toxicity to aquatic algae and cyanobacteria

Description of key information

EC50 (72 h, growth rate) = 25.56 mg/L (Skeletome costatum, nominal, ISO 10253)
NOEC (72 h, growth rate) = 10 mg/L (Skeletome costatum, nominal, ISO 10253)
EC50 (72 h, growth rate) = 11 mg/L (Scenedesmus subspicatus, nominal, read-across, EU Method C.3)
NOEC (72 h, growth rate) = 3 mg/L (Scenedesmus subspicatus, nominal, read-across, EU Method C.3)

Key value for chemical safety assessment

EC50 for freshwater algae:

11 mg/L

EC50 for marine water algae:

25.56 mg/L

EC10 or NOEC for freshwater algae:

3 mg/L

EC10 or NOEC for marine water algae:

10 mg/L

Additional information

A study on the toxicity of C12-14AS MEA (CAS 90583-16-7) to the marine alga Skeletonema costatum by Hudson (2003) is available. The study was conducted according to GLP and ISO 10253. The solutions were prepared as water accomodated fractions (WAF). The EC50 (72 h) and NOEC (72 h) for growth rate were determined to be 25.56 and 10 mg/L, respectively.

Moreover, read-across to other structurally related category members was conducted and corroborates the findings of the study mentioned above. Read-across data from the following similar C12-14 mixtures were used: C12-14AS TEA (CAS 90583-18-9) and C12-14AS Na (CAS 85586-07-8). Toxicity of alkyl sulfates is dependent on the carbon chain length and the influence of the counter ion can be neglected.

The study investigating toxic effects of C12-14AS TEA (CAS 90583-18-9) to freshwater algae Desmodesmus subspicatus was performed according to EU Method C.3 and GLP principles (Scholz 1996). Growth inhibition caused by the test substance was determined after 24, 48 and 72 h of exposure under static conditions to seven test concentrations up to 300 mg/L as anionic active substance (nominal values in agreement with the measured values). The results show that the 72-hour EC50 value for growth rate was 11 mg a.i./L for growth rate and 9.3 mg a.i./L for biomass (nominal concentrations). The NOEC value for growth rate was determined to be 3 mg a.i./L (nominal concentration). Due to structural and property similarity with the tested category member, the 72-hour EC50 value of 11 mg/L and NOEC of 3 mg/L (both for growth rate) is considered as reliable for C12-14 MEA (CAS 90583-16-7) for freshwater algae.

The toxicity of sulfuric acid, mono-C12-14 alkyl esters, sodium salts (CAS 85586-07-8) to aquatic algae was investigated in the GLP-compliant study with Desmodesmus subspicatus according to EU Method C.3 (Scholz 1995). Algae were exposed to six test concentrations up to 20 mg/L (nominal concentration corresponding to 17 mg/L of measured concentration). The study resulted in the 72-hour EC50 value for growth rate of above 20 mg a.i./L (nominal concentration). The EC10 (72 h) for growth rate was 5.4 mg a.i./L (nominal concentration).

Additional information about the toxicity of C12-14AS Na to algae is available from a publication by Verge and Marino 1996. The authors performed a non-GLP-study with Selenastrum capricornutum, according to OECD guideline 201. In this study the EC50 (72 h) for growth rate was determined to be 27 mg/L.