Hexaphenoxycyclotriphosphazene

Short-term toxicity to aquatic invertebrates

Description of key information

A 48-hour acute Immobilization test of FP-100 with Daphnia magna was conducted.
The results were estimated based on the time-weighted mean of the measured concentrations, 0.0495 mg/L, because the measured values of the test item concentration in the test solution were not kept within ±20% of the nominal concentration.
Both the 24-hour and 48-hour EC50 (Median Effective Concentration) of FP-100 were >0.0495 mg/L.
No abnormal effects on the test organisms were observed at the exposure concentration.
Consequently, both the highest test concentration which caused 0% immobility and the NOEC (No Observed Effect Concentration) after 48-hours exposure were 0.0495 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.05 mg/L

Additional information

A 48-hour acute Immobilization test of FP-100 with Daphnia magna was conducted.   Twenty test organisms were used in one exposure level (nominal concentration: 0.100 mg/L), a vehicle control and a control. The water temperature was maintained within the range of 20±1°C. The semi-static system, renewal at 24 hours for the test. In the preliminary tests the solubility of the test item to dilution water was not reproducible, and the concentration in dispersed suspension containing the test item was not detected. So the test concentration was decided from the concentration which was expected to maintain the concentration in test solution prepared with N,N-Dimethylfomamide (DMF) during exposure and be more than the solubility.   The measured concentrations of the test item in the test solution were 66.5 and 79.9% of the nominal concentration at the preparation and after the renewal, and 23.5 and 40.0% before the renewal and at the end of exposure, respectively. The results were estimated based on the time-weighted mean of the measured concentrations, 0.0495 mg/L, because the measured values of the test item concentration in the test solution were not kept within ±20% of the nominal concentration.   Both the 24-hour and 48-hour EC50 (Median Effective Concentration) of FP-100 were >0.0495 mg/L. No abnormal effects on the test organisms were observed at the exposure concentration.   Consequently, both the highest test concentration which caused 0% immobility and the NOEC (No Observed Effect Concentration) after 48-hours exposure were 0.0495 mg/L. The measured concentration of the test item of the test solution was not kept within ±20% of the nominal concentration during the test. However, it was considered that the concentration of the test item in the test solution was maintained higher than the solubility to the test medium expected from the measured values at 24 hours after preparation of the test solution. Therefore, it is concluded that the test item has no potential for adverse effects on the test organisms near the solubility of the test item to the test medium.