Silicic acid, aluminum magnesium sodium salt

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

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)

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes (incl. QA statement)

Remarks:

(Landesamt für Umwelt-, Wasserwirtschaft und Gewerbeaufsicht, Rheinland-Pfalz

Specific details on test material used for the study:

Name: Silicic acid Aluminium Magnesium Sodium Salt
Batch no. code # 1107274003
Appearance: white powder
Composition: Silicic acid Aluminium Magnesium Sodium Salt
CAS No. 12040-43-6
EINECS-No. 234-919-5
Purity > 99 %
Homogeneity homogeneous
Vapour pressure: not volatile
Stability: stable at room temperature
Solubility: poorly soluble
Production date: not stated
Expiry date O1. Nov. 2018
Storage: room temperature 20 +/- 5 °C, dry

Analytical monitoring:

yes

Details on sampling:

Selection of Daphnia
23 ± 1 hours before the start of the test, the adult animals were separated from the young.
Approximately 0.5 hours before test start, the adults were caught with the help of a glass tube, and the newborn Daphnia, aged between 0 and 23 hours, were sieved from the medium and immediately placed into a 250 mL-beaker containing dilution water. After a settling-in period of 30 minutes, animals which showed no apparent damage were used for the test.
Switching from M4-medium (husbandry) to ISO-medium (test) has been shown not to cause any detrimental effects for test Daphnia.

Test organisms (species):

Daphnia magna

Details on test organisms:

Species: Daphnia magna
Variety: STRAUS
Strain: Berlin
Sex: female
Age between 0 and 24 hours
Origin: Umweltbundesamt Berlin
In-house breeding since 27. September 2007
Selection of the test system was made following the proposal of the guidelines.

Animal Husbandry
Daphnia magna is bred in the LAUS GmbH throughout the year. The animals are kept for the use in toxicity tests. They multiply by parthenogenesis, thus being genetically identical.
The husbandry is performed similar to the method described in EN ISO 6341, following SOP 115 002 01 („Zucht und Hälterung von Daphnia magna STRAUS“), edition 11, adopted 15. January 2013.
Vessels preserving glasses, nominal volume 2 L
Medium M4-Medium (recipe of ELENDT), composition see annex
Food unicellular green algae (Desmodesmus subspicatus)
Medium renewal: twice a week
Photo period: 16/8 hours, using neon tubes
Temperature: 20 ± 2 °C

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Hardness:

Resulting hardness in mmol/L: 2.502
Resulting hardness in mg CaCO3/L: 250

Test temperature:

18-19°C

pH:

After preparation, the dilution water is aerated, and the pH is adjusted to 7.8 ± 0.2.

Dissolved oxygen:

Nominal Concentration in mg/L O2-Concentration in mg/L nach 48h
0 9.0
100 8.9

Nominal and measured concentrations:

100 mg/L nominal

Details on test conditions:

Duration: 48 hours
Observation times: 24 and 48 hours
Feeding: none
Lighting: diffuse lighting
Test vessels: glass beakers, nominal volume 50 mL, tall shape
Replicates four vessels, each containing 20 mL test solution and five Daphnia
Control four vessels, each containing 20 mL dilution water and five Daphnia

Reference substance (positive control):

yes

Remarks:

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study (14070901R201) which was performed in August 2014. The 24h-EC50 was determined as 1.2 mg/L, lying within the demanded range of 0.6 – 1.7 mg/L.

Key result

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

24 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

One valid experiment was performed. The study was performed using a nominal loading of 100 mg/L. Due to the poor solubility of the test item, the water-accommodated fraction was prepared for the test. Twenty Daphnia were exposed to the test item for 48 hours in a static test system. None of the animals were immobilised in the control or the treatment. At the beginning and at the end of the test, the concentration of aluminium as a component of the test item in the test solutions was determined using ICP-OES measurement. Neither in the treatment nor in the control aluminium was detectable. Therefore the determination of the biological results was based on the nominal loading.

Validity criteria fulfilled:

yes

Conclusions:

Up to a nominal loading of 100 mg/L Silicic acid Aluminium Magnesium Sodium Salt shows no toxicity to aquatic invertebrates like Daphnia magna.

Executive summary:

The study was performed using a nominal loading of 100 mg/L. Twenty Daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised Daphnia were counted. None of the animals were immobilised in the control or the treatment.

Description of key information

Up to a nominal loading of 100 mg/L Silicic acid Aluminium Magnesium Sodium Salt showed no toxicity to aquatic invertebrates like Daphnia magna.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L