2-[(8-amino-7-{[4-substituted-2-sulfonatophenyl]diazenyl}-1-hydroxy-3,6-disulfonaphthalen-2-yl)diazenyl]-4-[(4-chloro-6-{[3-(substituted)phenyl](ethyl)amino}-heteromonocycl-2-yl)amino]arylsulfonic acid, potassium and sodium salts

Toxicity to aquatic algae and cyanobacteria

Description of key information

The substance had a negative impact on the growth rate and biomass yield of green algae after exposure for 72 hours.

Key value for chemical safety assessment

EC50 for freshwater algae:

35 mg/L

EC10 or NOEC for freshwater algae:

13 mg/L

Additional information

The acute aquatic toxicity of the test item FAT 40849/A TE was tested in a valid GLP study according to EU Method C.3 by exposing the freshwater green algae Pseudokirchneriella subcapitata for 72 hours in a static toxicity test. A series of nominal concentrations of 2.2, 4.6, 10, 22, 46 and 100 mg/L was tested. The nominal concentrations were confirmed by analysis by HPLC and measured concentrations were 8.7, 11, 46 and 102 mg/L (the lowest two test concentrations were not analysed). A negative impact on the growth rate of green algae was seen and the corresponding EC50 value was >100 mg/L and the EC10 value was 25 mg/L. The negative impact on biomass yield was stronger and the corresponding EC50 value was 35 mg/L and the EC10 value was 13 mg/L.