Caesium iodide

Short-term toxicity to fish

Description of key information

Under the conditions of this acute fish toxicity study the observed end points for the effect of cesium iodide were the followings: 96h NOEC value: ≥ 100 mg test item/L 96h LOEC value: > 100 mg test item/L 96h LC50 value: > 100 mg test item/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L

Additional information

Acute toxicity of the test item cesium iodide was assessed with Acute Fish Toxicity Test on Zebrafish (Danio rerio) over an exposure period of 96 hours in a static system. The recorded effects were mortality and symptoms of intoxication of the fish. Based on the results of a preliminary range finding test, a limit test was performed: one control and the concentration of 100 mg/L of the test item were tested according to the relevant guideline (OECD 203). Both test groups comprised seven zebrafish and 5 L test solution. No replicates were tested. The test was considered to be valid because assay acceptance criteria were fulfilled. Analytical determination of the test concentration was performed by flame photometry. The measured concentration of cesium iodide was within the target range (± 20 % of the nominal concentration): 93 % of the nominal concentration was measured at the start and 98 % at the end of the test. The measured concentrations varied between 93 % and 99 % of the nominal concentration. Based on the analytical results, the test concentration did not differ from the nominal concentration significantly, hence the biological results based on the nominal concentration of 100 mg/L. No mortality or clinical symptoms were observed in the control and in the 100 mg/L test item treated group.

Under the conditions of this acute fish toxicity study the observed end points for the effect of cesium iodide were the followings: 96h NOEC value: ≥ 100 mg test item/L 96h LOEC value: > 100 mg test item/L 96h LC50 value: > 100 mg test item/L.