Registration Dossier

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

ErC50-72h of 45 mg/L for aquatic algae was determined. Therefore, 1,2,4 triazole is considered as harmful to algae.

Key value for chemical safety assessment

EC50 for freshwater algae:
45 mg/L
EC10 or NOEC for freshwater algae:
3.5 mg/L

Additional information

The acute toxicity of 1,2,4 Triazole to Pseudokirchnerella subcapitata has been investigated in an OECD 201 test according to GLP requirements (Thiebaud & Bouraly, 1998). In the test conditions, the ErC50 -72h is 45 mg/L and the NOEC is 3.49 mg/L. The test concentrations were maintained within 80% during the test. Therefore, 1,2,4 Triazole is considered as harmful to algae.

Another test similar to OECD guideline 201 has been performed and can be used as a supportive study (De Morsier, 1982). The cell concentration was determined at 120 hours instead of at least at 24, 48 and 72 hours after the start of the test. Therefore only an EC50-value after 5 days is given. in addition, concentrations were not maintained within 80% during the test. The EC50 -5d was determined to be 6.3 mg/L (nominal concentrations).