C8-18 alkylampho(di)propionates

Toxicity to aquatic algae and cyanobacteria

Description of key information

The acute toxicity of the substance to freshwater algae (Pseudokirchneriella subcapitata) was investigated in 2 studies. In a 72 h toxicity study (classified as reliable without restrictions), freshwater algae (Pseudokirchneriella subcapitata) were exposed to the substance according to OECD 201 and GLP principles. The 72h-ERC50 for growth rate reduction was 87 mg/L, corresponding to 33 mg solids/L, based on average measured exposure concentrations. The NOEC for growth rate reduction was 2.1 mg/L corresponding to 0.82 mg solids/L. In a 72 h toxicity study, of which the reliability could not be assigned, freshwater algae (Pseudokirchneriella subcapitata) were exposed to the substance according to OECD 201 but not under GLP principles. The 72h-ERC50 for growth rate reduction was 3.7 mg/L, corresponding to 1.4 mg solids/L, based on nominal concentrations (no analytical verification of test concentratuions). The 72h-ERC10 was 2.0 mg/L, which corresponds to 0.8 mg solids/L.
The ERC50 value obtained in the study classified as reliable without restrictions is taken as key value for CSA since it was considered the most reliable.

Key value for chemical safety assessment

EC50 for freshwater algae:

87 mg/L

EC10 or NOEC for freshwater algae:

2.1 mg/L

Additional information

The acute toxicity of the substance to aquatic algae was investigated in 2 studies:

Tobor-Kapłon (2013) - In a 72 h toxicity study, freshwater algae (Pseudokirchneriella subcapitata) were exposed to the substance according to OECD guideline Nr. 201and GLP principles. Freshwater algae were exposed to the following nominal concentrations:

- Full test 1: 0 (control), 1.0, 3.2, 10, 32 and 100 mg/L, corresponding to 0.39, 1.2, 3.9, 12 and 39 mg solids/L

- Full test 2: 0 (control), 52, 78, 117, 174 and 259 mg/L, corresponding to 20, 30, 45, 67 and 100 mg solids/L.

The substance did not reduce growth rate and inhibited the yield of this fresh water algae species significantly at an average measured exposure concentration of 2.1 mg/L corresponding to 0.82 mg solids/L (NOEC, based on full test 1). The 72h-ERC50 for growth rate reduction was 87 mg/L, corresponding to 33 mg solids/L, with a 95% confidence interval ranging from 67 to 112 mg/L (26 – 43 mg solids/L) based on average exposure concentrations (determined in full test 2). The present toxicity study is classified as reliable without restrictions.

 

Romstad and Källqvist (1992) – In a 72 h toxicity study, freshwater algae (Pseudokirchneriella subcapitata) were exposed to the substance according to OECD 201 but not under GLP principles. Algae were exposed to the following nominal concentrations: 0 (control), 1.8, 3.2, 5.6, 10, 18, 32 and 56 mg/L, corresponding to 0.69, 1.2, 2.2, 3.9, 6.9, 12 and 22 mg solids/L. The 72h-ERC10 for growth rate reduction was 2.0 mg/L, which corresponds to 0.8 mg solids/L, based on nominal concentrations. The 72h-ERC50 for growth rate reduction was 3.7 mg/L, corresponding to 1.4 mg solids/L, based on nominal concentrations. The reliability of the study could not be assigned as the study was not performed according to GLP principles, there was no data about the (latest) sensitivity check by means of a positive control and no analytical verification of the test concentrations.

Selection of key study

The study conducted by Tobor-Kapłon (2013) was selected as the key study since it was considered the most reliable. The Romstad and Källqvist (1992) study was not performed according to GLP principles, there was no data about the (latest) sensitivity check by means of a positive control and no analytical verification of the test concentrations.