Registration Dossier

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Concerning the toxicity to algae, the fresh water algae Pseudokirchnerella subcapitata was exposed to cyclohexylamine for 72 hours. The experiment was conducted according to OECD Guideline 201 yielding a 72 -h NOEC of 10.3 mg/L and a 72-h EC50 of 29.3 mg/L having inhibition of growth as endpoint (MITI, 1997).

Key value for chemical safety assessment

EC50 for freshwater algae:
29.3 mg/L
EC10 or NOEC for freshwater algae:
10.3 mg/L

Additional information

The present test was conducted without pH adjustment and pH values increased with increasing test item concentrations. Concluding, it can be assumed that observed effects are caused by the prevailing pH values. Supportive, acute toxicity tests towards fish (MITI, 1997) observed no adverse effects performing tests in neutralized media at a test item concentration of 100 mg/L. The present study was used in the scope of environmental risk assessment as it shows that the pH might be a crucial factor determining adverse effects towards aquatic life rather than the presence of the test item itself. Concluding, there is no risk of underestimating the environmental hazard using that study and environmental hazards of the test item towards aquatic life are adequately assessed.