Cerium(4+) disulphate

Endpoint summary

Description of key information

Acute aquatic toxicity
Algae were the most sensitive species in acute toxicity tests with the test substance, according to OECD guideline, resulting in a 72 -hour EC50 and EC10 of 0.541 mg/L and 0.380 mg/L (calculated value for anhydrous substance), respectively. Based on acute aquatic toxicity results obtained, the substance has to be classified as environmental acute toxic cat. 1 (H400) according to Regulation (EC) No 1272/2008 (CLP).

Chronic toxicity
The test substance was tested in an aquatic toxicity test with algae, according to OECD guideline 201. The 72 -hour EC50 and EC10 for growth rate was 0.541 and 0.380 mg/L (calculated value for anhydrous substance), and 72 -hour NOEC 0.456 mg/L (calculated value for anhydrous substance). Thus, the substance has to be classified as environmental chronic toxic cat. 1 (H410) according to Regulation (EC) No 1272/2008 (CLP).

The EC50 at 48 hours with Daphnia magna was determined to be 1.19 mg/L (hydrated substance) and 0.98 mg/L (calculated for anhydrous substance). The EC50 and EC10 based on growth rate to the green algae Raphidocelis subcapitata, were 0.658 and 0.462 mg/L (hydrated substance) and 0.541 and 0.380 mg/L (calculated for anhydrous substance), respectively.

Additional information

Short-term toxicity to invertebrates

In the acute immobilisation test (reference 6.1.3-1) with Daphnia magna (STRAUS), the effects of the test item were determined according to OECD Guideline for testing of chemicals, Guideline No. 202, adopted 13th April 2004. The study was conducted in a static system over a period of 48 hours with nominal concentrations of 6.25, 12.5, 25, 50 and 100 % v/v saturated solution (corresponding to geometric measured concentrations of NA, 0.20, 0.28, 0.77 and 1.83 mg/L. The validity criteria of the test guideline were fulfilled. The 48-h EC50 value was determined to be 1.19 mg/L (hydrated substance) and 0.98 mg/L (calculated for anhydrous substance).

Toxicity to aquatic algae

The effect of the test item on the growth of a unicellular green algal species Raphidocelis subcapitata was determined according to OECD 201, Regulation (EC) No. 226/2016 Method C.3 and EPA OPPTS 850.5400 and under GLP (reference 6.1.5 -1). The study was conducted under static conditions with an initial cell density of 1x10^4 cells/mL for a period of 72 hours. A stock solution of 100 mg/L was freshly prepared with OECD Medium and shaken overnight and the non-dissolved test material was separated by filtration. Six concentrations were tested in a geometrical series with a dilution factor of 2: 6.25, 12.5, 25, 50 and 100 % v/v saturated solution ((corresponding to 0.298, 0.391, 0.555, 0.786 and 1.105 mg/L (calculated geometric mean concentrations)). The EC50values for inhibition of growth rate (ErC50) was 0.658 mg/L (hydrated substance) and 0.541 mg/L (calculated value for anhydrous substance),and for inhibition of yield (EyC50) 0.507 mg/L (hydrated substance) and 0.417 mg/L (calculated value for anhydrous substance).The EC10value was determined to be 0.462 mg/L (hydrated substance) and 0.380 mg/L (calculated value for anhydrous substance)based on growth rate (ErC10) and 0.346 mg/L (hydrated substance) and 0.284 mg/L (calculated value for anhydrous substance) based on yield (EyC10).