Sulfuric acid, C10-12 (even numbered)-alkyl esters, sodium salts

Long-term toxicity to aquatic invertebrates

Description of key information

21d NOEC (Daphnia magna, reproduction) = 1.2 mg/L

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1.2 mg/L

Additional information

Since no reliable chronic test involving aquatic invertebrates is available for C10-12AS Na (CAS 85049-86-1), in accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5, a read-across to other structurally related category members was conducted. Read-across data from the following substances were used: C10AS Na (CAS 142-87-0) and C12AS Na (CAS 151-21-3), since toxicity of alkyl sulfates is dependent on the carbon chain length.

One long-term toxicity study with Daphnia magna is available for C10AS Na (CAS 142-87-0; BASF 2012). The test was performed according to OECD 211 guideline and GLP principles. Daphnids were exposed for 21 days under semi-static conditions to six test concentrations up to 6.86 mg/L (measured concentration). The followed parameters included mortality and reproduction of daphnids. The NOEC value based on the reproduction was determined to be 1.4 mg/L and the LOEC value as 6.86 mg/L (measured concentrations). The NOEC value for C10AS Na of 1.4 mg/L was further used for the derivation of C10-12AS Na (CAS 85049-86-1) NOEC.

A non-GLP, 7-day reproduction toxicity test with Ceriodaphnia dubia performed according to EPA-600/489/001 guideline is available for CAS 151-21-3 (Lauth 1996). Daphnids were exposed under flow-through conditions to five test concentrations up to 8 mg/L. Analytical check of test concentration proved that the nominal concentrations were in agreement with the measured ones. Mortality and reproduction were evaluated daily. The NOEC value determined after 7 days of exposure to test substance was 0.88 mg/L (measured concentration). The result of Lauth (1996) is supported by a publication from LeBlanc (1982). In this non-GLP, 40-day test Daphnia magna was exposed to CAS 151-21-3 up to 8 mg/L (nominal concentration) over four consecutive generations under semi-static conditions. No special guideline was followed. Offspring daphnids of less than 24 hours of age were collected after 10 days of exposure to the test substance and exposed for another 10 days. This procedure was repeated three times. The overall NOEC ranged from 2 to 4 mg/L (nominal concentrations, analytics not performed). The NOEC value for C12AS Na of 0.88 mg/L was further used for the derivation of C10-12AS Na (CAS 85049-86-1) NOEC.

Due to structural and property similarities with the tested category member these results also can be used to determine the long-term toxicity to aquatic invertebrates of C10-12AS Na (CAS 85049-86-1). Based on the results available from the Ceriodaphnia dubia and Daphnia magna tests, it can be seen that C. dubia is more sensitive to alkyl sulfates than D. magna. Therefore, the NOEC values obtained in C. dubia testing can be used as the conservative values in order to determine a 21-NOEC value of C10-12AS Na (CAS 85049-86-1) for D. magna. The composition of C10-12AS Na (CAS 85049-86-1) used for the NOEC calculation was based on the normalized mean values of provided ranges: C10: 72% and C12: 28%. The NOEC values of C10AS Na (CAS 142-87-0) and C12 -AS Na (CAS 151-21-3) were 1.4 mg/L and 0.88 mg/L respectively. Using the additivity formula stipulated in the EC Regulation 1272/2008, the NOEC value of C10-12AS Na (CAS 85049-86-1) is 1.2 mg/L.

Since the result of Daphnia reproduction test was the lowest chronic aquatic effect value, the NOEC of 1.2 mg/L was used for the PNEC calculation.