Alkali salt of (sulfonato oxyethane sulfonyl) arylamino triazinylamino sulfonato (sulfonato arylazo) aryl sulfonate

Endpoint summary

Additional information

A limit test was conducted to determine the acute toxicity of the test substance to Daphnia magna according to EU Method C.2, in compliance with GLP. In this test, 2 replicates of 10 Daphnia magna neonates were exposed to the test substance at a nominal concentration of 100 mg/L under static conditions for 48 h. Immobility was recorded at 24 and 48 h. The analytical concentration of the test substance was measured by HPLC method and was found to be 100% of the nominal value at 0 h, and 98.8% of the nominal value at 48 h. Under the test conditions, the 48 h EC50 and NOEC of the test substance were >100 mg/L and ≥100 mg/L (nominal concentrations) respectively (Weyers, 2006a).

A study was conducted to determine the acute toxicity of the test substance to the algae Desmodesmus subspicatus according to EU Method C.3, in compliance with GLP. Triplicate inocula of the algae were exposed to nominal concentrations of the test substance (0.9, 1.9, 4.3, 9.4, 20.7, 45.5 and 100 mg/L) for 72 h under static conditions. Quantification of the applied concentrations was carried out using HPLC. The measured concentrations of the test substance ranged from 99.5-103% of nominal values at 0 h, and from 101.5 - 109.7% of nominal values at 72 h respectively. The cell densities were measured at 24, 48 and 72 h. Inhibition of the algal population was measured as reduction in growth and growth rate, relative to control cultures grown under identical conditions. Under the conditions of the study, the 72 h EbC10 (biomass) and ErC10 (growth rate) were determined to be 4.8 and 22.8 mg/L respectively; the EbC50 and ErC50 were determined to be 33.9 and 147 mg/L respectively; and the NOECs for biomass and growth rate were determined to be 1.9 and 4.3 mg/L respectively (Weyers, 2006b).