Cerium(4+) disulphate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13.09.2017 to 15.09.2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

The following nominal concentrations were tested: 6.25, 12.5, 25, 50 and 100 % v/v saturated solution. The corresponding calculated geometric mean concentrations were: NA, 0.20, 0.28, 0.77 and 1.83 mg/L. The immobility or mortality of the Daphnia was determined by visual observation after 24 and 48 hours of exposure. Those animals not able to swim within 15 seconds after gentle agitation of the test beaker were considered to be immobile.

Vehicle:

no

Details on test solutions:

The test solutions used in the test was prepared by mechanical dispersion without using any solubilising agents.
The test item is poorly water soluble material. For preparation of the test solutions a supersaturated solution (100 mg/L nominal loading) was first prepared by dispersing/dissolving an amount of 0.1 g test item into 1000 mL test medium (ISO medium). This solution was agitated by orbital shaker overnight and then the non-dissolved test material was separated by filtration through a membrane filter (0.22 µm) in order to obtain the saturated test solution (i.e. 100 % v/v saturated solution). The test solutions of subsequent concentrations were prepared by appropriate dilution of this stock solution.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Straus)
- Source: Laboratory of Hydrobiology (Central Agricultural Office, Directorate of Plant-, and Soil Protection) 2100 Gödöllő, Kotlán S. u. 3. Hungary
- Age of parental stock (mean and range, SD): Less than 24 hours old
- Feeding during test: no

ACCLIMATION
- Acclimation period: no
- Acclimation conditions: same as test

Test type:

static

Water media type:

other: ISO medium

Limit test:

no

Total exposure duration:

48 h

Hardness:

approximate 249 mg/L

Test temperature:

19.2 – 20.2°C.

pH:

7.19 – 8.00

Dissolved oxygen:

7.91 – 8.38 mg/L

Salinity:

not specified

Conductivity:

not specified

Nominal and measured concentrations:

nominal concentrations: 6.25, 12.5, 25, 50 and 100 % v/v saturated solution
geometric mean concentrations: NA, 0.20, 0.28, 0.77 and 1.83 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beaker
- Medium volume per beaker: at least 40 mL
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

OTHER TEST CONDITIONS
- Photoperiod: 16 h light and 8 h darkness
- Light intensity: 614 lux

RANGE-FINDING STUDY
- Test concentrations: 1, 10 and 100 mg/L (plus control)
- Results used to determine the conditions for the definitive study: no immobilisation at 10 mg/L and below, 100% immobilisation at 100 mg/L

Reference substance (positive control):

yes

Remarks:

Potassium dichromate, experimantal phase: 07 – 08 March 2017

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

1.19 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: measured value for hydrat

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

0.28 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: measured value for hydrat

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

0.77 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: measured value for hydrat

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.98 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: calculated value for anhydrous substance

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

0.23 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: calculated value for anhydrous substance

Results with reference substance (positive control):

24h EC50: 1.41 mg/L (95 % confidence limits: 1.19 – 1.68 mg/L)

Reported statistics and error estimates:

For determination of the ECx values Probit analysis was performed using SPSS software. Other endpoints were determined directly from the raw data.

Validity criteria fulfilled:

yes

Conclusions:

In this 48-hour static acute toxicity test with Daphnia magna the effects of Cerium(IV) sulfate tetrahydrate on the mobility was determined. The 48-h EC50 value was determined to be 1.19 mg/L (hydrated substance) and 0.98 mg/L (calculated for anhydrous substance). The 48-h NOEC was determined to be 0.28 mg/L (hydrated substance) and 0.23 mg/L (calculated for anhydrous substance).

Executive summary:

The purpose of this study was to evaluate the influence of the test item Cerium(IV) sulfate tetrahydrate on on the mobility, respectively survival of Daphnia magna in a static test system. Young Daphnia were exposed in an immobilisation test to aqueous test media containing the test item at 6.25, 12.5, 25, 50 and 100 % v/v saturated solution were ((corresponding to NA, 0.20, 0.28, 0.77 and 1.83 mg/L (calculated geometric mean measured concentrations)). Twenty Daphnia, divided into four groups of five animals each were exposed to the test item concentrations or run as control for 48 hours. The 48-h EC50 value was determined to be 1.19 mg/L (hydrated substance) and 0.98 mg/L (calculated for anhydrous substance). The 48-h NOEC was determined to be 0.28 mg/L (hydrated substance) and 0.23 mg/L (calculated for anhydrous substance).

Description of key information

The 48-h EC50 value was determined to be 1.19 mg/L (hydrated substance) and 0.98 mg/L (calculated for anhydrous substance).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.98 mg/L

Additional information

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).