Silicic acid, sodium salt

Toxicity to terrestrial arthropods

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to terrestrial arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

07 June - 09 August 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.3020 (Honey Bee Acute Contact Toxicity)

Deviations:

no

GLP compliance:

yes

Remarks:

no attest of authority; California Agricultural Research Inc., Kerman, CA, USA

Application method:

contact

Analytical monitoring:

no

Vehicle:

yes

Details on preparation and application of test substrate:

- Method of test material application: single topical dose
- Body part: thorax or abdomen
- Volume of test solution applied: 5 µL
- Controls: untreated and with 5 µL sterile water
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): sterile water

Test organisms (species):

Apis mellifera

Animal group:

Hymenoptera (honeybees)

Details on test organisms:

TEST ORGANISM
- Common name: honey bee, Italien strain
- Source: California Agricultural Reserach (CAR) Inc. bee yard (hives originally created in 2000 from packaged bees shipped by Bear River Honey Company, Wheatland, CA.)
- Age at test initiation (mean and range, SD): 1 to 5 days
- Cultural background (if honeybees):
- Disease free: yes
- Kept according to standard practices: yes


ACCLIMATION
- Acclimation: CAR bee yard; prior to study start all hives were inventoried for their general health, vigor, and brood conditions
- Health during acclimation (any mortality observed): no

Study type:

laboratory study

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

4, 6, 24, and 48 h

Test temperature:

26.73° to 35.79°C

Humidity:

31% - 74%

Details on test conditions:

TEST SYSTEM
- Test container (material, size): cube-shaped, wire mesh cages, appr. 12.7 cm to a side, constructed of 3.2 mesh/cm2 hardware cloth
- Amount of soil or substrate:
- No. of organisms per container (treatment): 40 - 45
- No. of replicates per treatment group: 4
- No. of replicates per control: 4
- No. of replicates per vehicle control: 4


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality


VEHICLE CONTROL PERFORMED: yes

Nominal and measured concentrations:

25 µL a.i./bee

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

LD0

Effect conc.:

25 µg per animal

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

LD50

Effect conc.:

> 25 µg per animal

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Details on results:

- Mortality at end of exposure period: zero
- Morphological abnormalities: none
- Behavioural abnormalities: none

Under the conditions of this study, there was no evidence of harmful effects or increased mortality caused by acute contact with AgSil ¿ 25.

Reference 2

Endpoint:

toxicity to terrestrial arthropods: short-term

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Justification for type of information:

Refer to category justification provided in IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Application method:

contact

Duration:

48 h

Dose descriptor:

LD0

Effect conc.:

25 µg per animal

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other:

Remarks:

Source, key, 1312-76-1, Richards 2006

Duration:

48 h

Dose descriptor:

LD50

Effect conc.:

> 25 µg per animal

Nominal / measured:

meas. (not specified)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other:

Remarks:

Source, key, 1312-76-1, Richards 2006

Additional information

No test available on sodium silicate. Data considered here is read-across from potassium silicate based on an analogue-approach. In a GLP guideline study with honey bees by Richards (2006), following EPA OPPTS 850.3020 (Honey Bee Acute Contact Toxicity), for a potassium silicate solution (29.1 wt %) the 48 h LD0 and L50 were determined to be 25 ug and > 25 ug active matter per animal, respectively.