Silicic acid, lithium salt

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

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

Adequacy of study:

supporting study

Study period:

20 Oct 2004 - 03 Nov 2004

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP-study, which meets national standard methods tested with the source substance AgSil TM 25 Potassium Silicate Solution. According to the ECHA guidance document “Practical guide 6: How to report read-across and categories (March 2010)”, the reliability was changed from RL1 to RL2 to reflect the fact that this study was conducted on a read-across substance.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Version / remarks:

1998

Deviations:

no

GLP compliance:

yes

Remarks:

Product Safety Laboratories

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1312-76-1 (content: 30%)

IUPAC Name:

1312-76-1 (content: 30%)

Details on test material:

- Name of test material (as cited in study report): AgSil TM 25 Potassium Silicate Solution
- Physical state: clear to hazy white, thick liquid
- Composition of test material, percentage of components: 70% water, 30% silicic acid, potassium salt, potassium silicate
- Lot/batch No.: C052804K1
- Stability under test conditions: stable for the duration of testing
- Storage condition of test material: at room temperature
- Other: ratio: 2.47; specific gravity: 1.231 g/mL, pH: 11.3

Test animals

Species:

rat

Strain:

other: Sprague-Dawley derived albino

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Ace Animals Inc., Boyertown, PA, USA
- Age at study initiation: 8 - 9 weeks
- Weight at study initiation: 251 - 280 g (males) and 175 - 210 g (females)
- Housing: sngly in stainless steel cages with mesh floors
- Diet: Purina Rodent Chow #5012
- Water: filtered tap water supplied ad libitum by an automatic water dispensing system
- Acclimation period: 8 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 - 22
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: From: 20 Oct To: 3 Nov 2004

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: clipped dorsal area and the trunk
- % coverage: 10% (2 inches x 3 inches)
- Type of wrap if used: Durapore tape

REMOVAL OF TEST SUBSTANCE
- Washing (if done): after removal of the pads, the test sites were gently cleansed of any residual test substance
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount(s) applied: 0.406 mL test substance/100 g bw; individual doses were calculated based on the initial body weights, taking into account the specific gravity of the test substance.

Duration of exposure:

24 h

Doses:

5000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animals were observed for mortality, signs of gross toxicity, and behavioral changes during the first several hours after application and at least once daily thereafter for 14 days. Observation included gross evaluation of skin and fur, eyes and mucous membranes, respiratory, circulatory, autonomic and central nervous systems, somatomotor activity and behavior pattern. Particular attention was directed to observation of tremors, convulsions, salivation, diarrhea and coma. Individual body weights were recorded prior to test substance application (initial) and again on days 7 and 14.
- Necropsy of survivors performed: yes; all rats were euthanized via CO2 inhalation on day 14. Gross necropsies were performed on all animals. Tissues and organs of the thoracic and abdominal cavities were examined.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Remarks:

silicic acid, potassium salt solution (30%)

Mortality:

All animals survived

Clinical signs:

other: All rats appeared healthy and active. Apart from the dermal irritation and alopecia there were no other signs of toxicity.

Gross pathology:

No gross lesions were observed at final necropsy in any animal.

Other findings:

Dermal irritation (erythema) and alopecia was noted at the application site of five animals (4 females and 1 male) between days 1 and 8.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

CLP: not classified
DSD: not classified