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EC number: 215-687-4 | CAS number: 1344-09-8
- Life Cycle description
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- Endpoint summary
- Appearance / physical state / colour
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- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
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- Long-term toxicity to aquatic invertebrates
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- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
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- Exposure related observations in humans
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- Additional toxicological data
Endpoint summary
Administrative data
Description of key information
Sodium silicate can be irritating to corrosive to the skin of rabbits, depending on the molar ratio and concentration.
Key value for chemical safety assessment
Skin irritation / corrosion
Link to relevant study records
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- supporting study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Study according to OECD Guideline, but only 1 animal tested.
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
- Deviations:
- yes
- Remarks:
- only one animal tested
- GLP compliance:
- yes
- Remarks:
- Inveresk Research International
- Species:
- rabbit
- Strain:
- New Zealand White
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS:
- Sex: female
- Source: Cheshire Rabbit Farms Ltd.
- Age: approx. 11 weeks
- Weight at study initiation: 2.3 - 3.0 kg - Type of coverage:
- semiocclusive
- Preparation of test site:
- shaved
- Vehicle:
- unchanged (no vehicle)
- Controls:
- not specified
- Amount / concentration applied:
- Concentration: 40.9 other: wt%; 0.5 mL
- Duration of treatment / exposure:
- The exposure lasted 1 min, 1 hr or 4 hrs.
- Observation period:
- up to 5 days
- Number of animals:
- 1
- Details on study design:
- - Removal of test substance: yes (washed away with water)
- Scoring system: according to Draize
- Examination time points: 1, 24, 48, 72 hours and 5 days - Irritation parameter:
- primary dermal irritation index (PDII)
- Score:
- 3
- Reversibility:
- other: Effects persisted for at least 5 days.
- Interpretation of results:
- irritating
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- supporting study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Study according to OECD Guideline, but only 1 animal tested.
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
- Deviations:
- yes
- Remarks:
- only one animal tested
- GLP compliance:
- yes
- Remarks:
- Inveresk Research International
- Species:
- rabbit
- Strain:
- New Zealand White
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS:
- Sex: male
- Source: Cheshire Rabbit Farms Ltd.
- Age: approx. 11 weeks
- Weight at study initiation: 2.3 - 3.0 kg - Type of coverage:
- semiocclusive
- Preparation of test site:
- shaved
- Vehicle:
- unchanged (no vehicle)
- Controls:
- not specified
- Amount / concentration applied:
- Concentration: 39.9 other: wt%; 0.5 mL
- Duration of treatment / exposure:
- The exposure lasted 1 min, 1 hr or 4 hrs
- Observation period:
- up to 5 days
- Number of animals:
- 1
- Details on study design:
- - Removal of test substance: yes (washed away with water)
- Scoring system: according to Draize
- Examination time points: 1, 24, 48, 72 hours and 5 days - Irritation parameter:
- primary dermal irritation index (PDII)
- Score:
- 3
- Reversibility:
- not reversible
- Interpretation of results:
- irritating
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- supporting study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Study according to OECD Guideline, but only 1 animal tested.
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
- Deviations:
- yes
- Remarks:
- only one animal tested
- GLP compliance:
- yes
- Remarks:
- Inveresk Research International
- Species:
- rabbit
- Strain:
- New Zealand White
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS:
- Sex: female
- Source: Cheshire Rabbit Farms Ltd.
- Age: approx. 11 weeks
- Weight at study initiation: 2.3 - 3.0 kg - Type of coverage:
- semiocclusive
- Preparation of test site:
- shaved
- Vehicle:
- unchanged (no vehicle)
- Controls:
- not specified
- Amount / concentration applied:
- Concentration: 39 other: wt%; 0.5 mL
- Duration of treatment / exposure:
- The exposure lasted 1 min, 1 hr or 4 hrs.
- Observation period:
- Examination time points: 1, 24, 48, 72 hours and 5 days.
- Number of animals:
- 1
- Details on study design:
- - Removal of test substance: yes (washed away with water)
- Scoring system: according to Draize - Irritation parameter:
- primary dermal irritation index (PDII)
- Score:
- 0
- Interpretation of results:
- not irritating
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- supporting study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Study according to OECD Guideline, but only 1 animal tested.
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
- Deviations:
- yes
- Remarks:
- only one animal tested
- GLP compliance:
- yes
- Remarks:
- Inveresk Research International
- Species:
- rabbit
- Strain:
- New Zealand White
- Type of coverage:
- semiocclusive
- Preparation of test site:
- shaved
- Vehicle:
- unchanged (no vehicle)
- Controls:
- not specified
- Amount / concentration applied:
- Concentration: 38.3 other: wt%
- Duration of treatment / exposure:
- uo to 4 hour(s)
- Observation period:
- 5 days
- Number of animals:
- 1
- Irritation parameter:
- primary dermal irritation index (PDII)
- Score:
- 0.33
- Interpretation of results:
- not irritating
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Guideline study, but no information on purity of test substance.
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
- GLP compliance:
- yes
- Remarks:
- Forsvarets Forskningsanstalt
- Species:
- rabbit
- Strain:
- other: White Landrace
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS:
- Source: Dörröds Djur -och Foderservice, Veberöd
- Weight at study initiation: 2.7 kg (average) - Type of coverage:
- semiocclusive
- Preparation of test site:
- shaved
- Vehicle:
- unchanged (no vehicle)
- Controls:
- no
- Amount / concentration applied:
- 0.5 g/mL applied
Concentration: 53.5 wt% in water - Duration of treatment / exposure:
- 4 hour(s)
- Observation period:
- One week for animals with no lesions and 14 days for animals with wounds.
- Number of animals:
- 3
- Details on study design:
- - Removal of test substance with water after 4 hrs exposure
- Scoring system: skin irritation index, according to OECD 404.
- Examination time points: 1, 24, 48 and 72 hours - Irritation parameter:
- primary dermal irritation index (PDII)
- Time point:
- other: 24, 48, 72 h
- Score:
- 8
- Reversibility:
- not reversible
- Irritation parameter:
- erythema score
- Basis:
- animal #1
- Time point:
- 24/48/72 h
- Score:
- 4
- Max. score:
- 4
- Reversibility:
- not reversible
- Remarks:
- observation for 14 d
- Remarks on result:
- probability of severe irritation
- Irritation parameter:
- erythema score
- Basis:
- animal #2
- Time point:
- 24/48/72 h
- Score:
- 4
- Max. score:
- 4
- Reversibility:
- not reversible
- Remarks:
- observation for 14 d
- Remarks on result:
- probability of severe irritation
- Irritation parameter:
- erythema score
- Basis:
- animal #3
- Time point:
- 24/48/72 h
- Score:
- 4
- Max. score:
- 4
- Reversibility:
- not reversible
- Remarks:
- observation for 14 d
- Remarks on result:
- probability of severe irritation
- Irritation parameter:
- edema score
- Basis:
- animal #1
- Time point:
- 24/48/72 h
- Score:
- 4
- Max. score:
- 4
- Reversibility:
- not reversible
- Remarks:
- observation for 14 d
- Remarks on result:
- probability of severe irritation
- Irritation parameter:
- edema score
- Basis:
- animal #2
- Time point:
- 24/48/72 h
- Score:
- 4
- Max. score:
- 4
- Reversibility:
- not reversible
- Remarks:
- observation for 14 d
- Remarks on result:
- probability of severe irritation
- Irritation parameter:
- edema score
- Basis:
- animal #3
- Time point:
- 24/48/72 h
- Score:
- 4
- Max. score:
- 4
- Reversibility:
- not reversible
- Remarks:
- observation for 14 d
- Remarks on result:
- probability of severe irritation
- Other effects:
- All exposed animals showed an acute necrosis. The necrosis and an acute oedema outside the wound remained during the following examinations.
- Interpretation of results:
- Category 1 (corrosive) based on GHS criteria
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Guideline study, but no information on purity of test substance.
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
- GLP compliance:
- yes
- Remarks:
- Forsvarets Forskningsanstalt
- Species:
- rabbit
- Strain:
- other: white landrace
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS:
- Source: Dörröds Djur -och Foderservice, Veberöd
- Weight at study initiation: 2.7 kg (average) - Type of coverage:
- semiocclusive
- Preparation of test site:
- shaved
- Vehicle:
- unchanged (no vehicle)
- Controls:
- no
- Amount / concentration applied:
- 0.5 g/mL applied
Concentration: 82% in water - Duration of treatment / exposure:
- 4 hour(s)
- Observation period:
- One week for animals with no lesions and 14 days for animals with wounds.
- Number of animals:
- 3
- Details on study design:
- - Removal of test substance with water after 4 hrs exposure
- Scoring system: skin irritation index, according to OECD 404.
- Examination time points: 1, 24, 48 and 72 hrs - Irritation parameter:
- primary dermal irritation index (PDII)
- Time point:
- other: 24, 48, 72 h
- Score:
- 4.6
- Reversibility:
- not fully reversible within: 1 animal had a wound that had not healed after 14 days. The skin on the other animal had healed after 14 days.
- Irritation parameter:
- erythema score
- Basis:
- animal #1
- Time point:
- 24/48/72 h
- Score:
- 4
- Max. score:
- 4
- Reversibility:
- not reversible
- Remarks:
- observation for 14 d
- Remarks on result:
- probability of severe irritation
- Irritation parameter:
- erythema score
- Basis:
- animal #2
- Time point:
- 24/48/72 h
- Score:
- 0
- Max. score:
- 0
- Remarks on result:
- no indication of irritation
- Irritation parameter:
- erythema score
- Basis:
- animal #3
- Time point:
- 24/48/72 h
- Score:
- 4
- Max. score:
- 4
- Reversibility:
- fully reversible within:
- Remarks:
- 14 d
- Remarks on result:
- probability of severe irritation
- Irritation parameter:
- edema score
- Basis:
- animal #1
- Time point:
- 24/48/72 h
- Score:
- 1.3
- Max. score:
- 2
- Reversibility:
- not reversible
- Remarks:
- observation for 14 d
- Remarks on result:
- probability of severe irritation
- Irritation parameter:
- edema score
- Basis:
- animal #2
- Time point:
- 24/48/72 h
- Score:
- 0
- Max. score:
- 0
- Remarks on result:
- no indication of irritation
- Irritation parameter:
- edema score
- Basis:
- animal #3
- Time point:
- 24/48/72 h
- Score:
- 4
- Max. score:
- 4
- Reversibility:
- fully reversible within: 14 d
- Remarks on result:
- probability of severe irritation
- Other effects:
- 2 of 3 animals showed necrotic skin lesions. 1 animal had a local necrosis which remained together with an acute oedema during the whole examination period. The second animal had a pigmented wound with an acute oedema which decreased to a slight oedema after 72 hrs. The third animal showed no skin irritancy. The fur grew fast on this animal, which made it difficult to obtain close contact between the test substance and the exposed area.
- Interpretation of results:
- other: probability of severe irritation
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Guideline study, but no information on purity of test substance.
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
- GLP compliance:
- yes
- Remarks:
- Forsvarets Forskningsanstalt
- Species:
- rabbit
- Strain:
- other: White landrace
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS:
- Source: Dörröds Djur-och Foderservice, Veberöd
- Weight at study initiation: 2.7 kg (average) - Type of coverage:
- semiocclusive
- Preparation of test site:
- shaved
- Vehicle:
- unchanged (no vehicle)
- Controls:
- no
- Amount / concentration applied:
- 0.5 g/mL applied
Concentration: 34.5 wt% in water - Duration of treatment / exposure:
- 4 hour(s)
- Observation period:
- One week for animals with no lesions and 14 days for animals with wounds.
- Number of animals:
- 3
- Details on study design:
- Test substance was removed with water after 4 hrs exposure.
- Scoring system: skin irritation index, according to OECD 404.
- Examination time points: 1, 24, 48 and 72 hours - Irritation parameter:
- primary dermal irritation index (PDII)
- Time point:
- other: 24, 48, 72 h
- Score:
- 0.4
- Reversibility:
- other: 1 of 3 rabbits had redness that persisted until 72 hrs and oedema observed only 48 hrs after exposure ended
- Irritation parameter:
- erythema score
- Basis:
- animal #1
- Time point:
- 24/48/72 h
- Score:
- 0
- Max. score:
- 0
- Remarks on result:
- no indication of irritation
- Irritation parameter:
- erythema score
- Basis:
- animal #2
- Time point:
- 24/48/72 h
- Score:
- 1
- Max. score:
- 1
- Reversibility:
- fully reversible
- Irritation parameter:
- erythema score
- Basis:
- animal #3
- Time point:
- 24/48/72 h
- Score:
- 0
- Max. score:
- 0
- Remarks on result:
- no indication of irritation
- Irritation parameter:
- edema score
- Basis:
- animal #1
- Time point:
- 24/48/72 h
- Score:
- 0
- Max. score:
- 0
- Remarks on result:
- no indication of irritation
- Irritation parameter:
- edema score
- Basis:
- animal #2
- Time point:
- 24/48/72 h
- Score:
- 0.3
- Max. score:
- 1
- Reversibility:
- fully reversible
- Irritation parameter:
- edema score
- Basis:
- animal #3
- Time point:
- 24/48/72 h
- Score:
- 0
- Max. score:
- 0
- Remarks on result:
- no indication of irritation
- Interpretation of results:
- GHS criteria not met
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- other information
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Guideline study, adapted to human conditions. No information on purity of test substance.
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
- Deviations:
- yes
- Remarks:
- study design adjusted to humans
- GLP compliance:
- yes
- Remarks:
- Henkel KGaA Dermatologie
- Species:
- human
- Type of coverage:
- semiocclusive
- Vehicle:
- water
- Amount / concentration applied:
- Concentration: 34.9 other: wt%
- Duration of treatment / exposure:
- 4 hour(s)
- Observation period:
- up to 72 h
- Number of animals:
- 20 (10 male and 10 female volunteers)
- Details on study design:
- 500 µL of undiluted sodium silicate or a 50% aqueous solution of the substance was applied to the inside of the lower arm and covered by a semi-occlusive patch, app. 1.5 cm2. 2 hrs after application, the site was examined for irritation, and removed if strong irritation was observed. The patch was removed after 4 hrs, and the test site rinsed.
The occurrence of erythema, oedema, flaking/dandruff and fissures in the skin was assessed according to Frosch' scoring system (PJ Frosch, AM Kligman: J Am Acad Dermatol 1, 1979, 35-41.). The scores were summed and an irritation score derived from the results. Sodium dodecylsulfate 20% was used a positive control, if the results did not differ significantly (p greater than or equal to 0.05) from those of the positive control, it was considered irritating. - Interpretation of results:
- not irritating
- Endpoint:
- skin irritation / corrosion, other
- Remarks:
- human volunteer study
- Type of information:
- experimental study
- Adequacy of study:
- other information
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Guideline study, adapted to human conditions. No information on purity of test substance.
- Principles of method if other than guideline:
- COLIPA open cutaneous test
- GLP compliance:
- yes
- Remarks:
- Henkel KGaA Dermatologie
- Species:
- human
- Type of coverage:
- open
- Vehicle:
- water
- Amount / concentration applied:
- Concentration: 34.9 other: wt%
application of 5, 10, 50% aqueous solutions and undiluted - Duration of treatment / exposure:
- 30 minute(s), the test substance was reapplied with a glass stick every 30 seconds. The test area on the inner lower arm was 3 cm2. After 30 minutes, the test area was rinsed with water and dried.
- Number of animals:
- 20 volunteers (10 male and 10 female)
- Details on study design:
- The adverse skin effects were scored for erythema and oedema until 30 minutes after the last application. The range ran from 0 (no reaction) to 4 (very strong redness spreading outside the test site and/or very strong oedema >2 mm). In addition the subjects were questioned to assess the occurrence of burning sensation, itching, pain, heat, cold.
- Interpretation of results:
- not irritating
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- other information
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Comparable to guideline study.
- Principles of method if other than guideline:
- comparable to Directive 2000/33/EC, B.40
- GLP compliance:
- no
- Species:
- rat
- Strain:
- Wistar
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS:
- Sex: Male
- Age: 28 days
- Weight at study initiation: 60-80 grams - Type of coverage:
- open
- Preparation of test site:
- shaved
- Vehicle:
- water
- Controls:
- not required
- Amount / concentration applied:
- Concentration: 52 other: wt%; 0.3 mL
- Duration of treatment / exposure:
- 4 hour(s)
- Interpretation of results:
- corrosive
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- other information
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Comparable to guideline study.
- Principles of method if other than guideline:
- comparable to Directive 2000/33/EC, B.40
- GLP compliance:
- no
- Species:
- rat
- Strain:
- Wistar
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS:
- Sex: Male
- Age: 28 days
- Weight at study initiation: 60-80 grams - Type of coverage:
- open
- Preparation of test site:
- shaved
- Vehicle:
- water
- Controls:
- not required
- Amount / concentration applied:
- Concentration: 44 other: wt%; 0.3 mL
- Duration of treatment / exposure:
- 24 hour(s)
- Interpretation of results:
- corrosive
- Endpoint:
- skin irritation: in vivo
- Type of information:
- experimental study
- Adequacy of study:
- other information
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Comparable to guideline study.
- Principles of method if other than guideline:
- comparable to Directive 2000/33/EC, B.40
- GLP compliance:
- no
- Species:
- rat
- Strain:
- Wistar
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS:
- Sex: Male
- Age: 28 days
- Weight at study initiation: 60-80 grams - Type of coverage:
- open
- Preparation of test site:
- shaved
- Vehicle:
- water
- Controls:
- not required
- Amount / concentration applied:
- Concentration: 38 other: wt%; 0.3 mL
- Duration of treatment / exposure:
- 24 hour(s)
- Number of animals:
- - Number of skin discs: 3
- Interpretation of results:
- corrosive
Referenceopen allclose all
AVERAGE SCORE:
- Erythema: 2
- Edema: 1
AVERAGE SCORE:
- Erythema: 2
- Edema: 1
No further details on "results" available.
AVERAGE SCORE:
- Erythema: 0
- Edema: 0
No further details on "results" available.
AVERAGE SCORE:
- Erythema: 0.33
- Edema: 0
REVERSIBILITY: At 48 hrs erythema was no longer observed.
AVERAGE SCORE:
- Erythema: 4
- Edema: 4
No further details on "results" available.
AVERAGE SCORE:
- Erythema: 2.6
- Edema: 2.0
No further details on "results" available.
AVERAGE SCORE:
- Erythema: 0.3
- Edema: 0.1
No further details on "results" available.
Clinical signs:
The undiluted test substance caused slight
scaling of the skin in 7/20 volunteers and strong scaling in
1/20. The total score was 0.45. Exposure to a 50% dilution
caused slight scaling of the skin in 7/20 volunteers and
strong scaling in 1/20, giving the total score 0.45.
Undiluted sodium silicate 37/40 caused scaling of
the skin in 8/20 volunteers, but is not considered
irritating to the skin. A 50% dilution of sodium silicate
37/40 resulted in scaling of the skin in 9/20 subjects,
giving a total score of 0.50.
The
positive control caused erythema within 2 hrs, with a score
of 21.8. The negative control, water, did not cause any
adverse effects.
Clinical signs:
Exposure to undiluted sodium silicate solution did
not cause any irritation. It rapidly hardened on the skin,
forming a wax-like coating. The 50% aqueous dilution caused
slight redness (barely perceptible erythema) in 3/20
volunteers 21-25 minutes after the exposure started, and
lasted 15-19 minutes. The 10% aqueous dilution caused slight
redness (barely perceptible erythema) in 2/20 volunteers 21and 25 minutes after the exposure started, and lasted 19 and
15 minutes, respectively. Exposure to 5% dilution
resulted in slight redness (barely perceptible erythema) in
2/20 volunteers, which started 25 and 21 minutes after the
first exposure and lasted 15 and 19 minutes in total,
respectively. A third volunteer had a slight itch that
started right after the exposure ended, and lasted 30
minutes. All the adverse effects were reversible.
Under non-occlusive conditions the 5, 10 and 50% aqueous
dilutions of the sodium silicate solution caused slight irritation
(barely perceptible erythema). The undiluted sodium silicate solution
did not cause irritation.
AVERAGE SCORE:
- Erythema: not applicable
- Oedema: not applicable
ELECTRICAL RESISTANCE VALUE (kOhm.disc): kOhm.disc (1hr):
1.1 (SD 0.3), kOhm.disc (4hrs): 0.9 (SD 0.1)
ANY OTHER INFORMATION: The substance is predicted to be
corrosive.
ELECTRICAL RESISTANCE VALUE (kOhm.disc):
kOhm.disc (1 hr) : 4.6 (SD 1.3)
kOhm.disc (4hrs) : 3.5 (SD 1.5)
kOhm.disc (24 hrs): 1.1 (SD 0.6)
ANY OTHER INFORMATION: 4 hr exposure: resistance measured at
24 hrs: 7.6 (SD 1.4)
The substance is predicted to be corrosive.
ELECTRICAL RESISTANCE VALUE (kOhm.disc):
kOhm.disc (1 hr) : 7.3 (SD 2.5)
kOhm.disc (4 hrs) : 2.8 (SD 0.3)
kOhm.disc (24 hrs): 1.6 (SD 0.1)
ANY OTHER INFORMATION: 4 hr exposure: resistance measured at
24 hrs: 7.5 (SD 0.2)
The substance is predicted to be corrosive.
Eye irritation
Link to relevant study records
- Endpoint:
- eye irritation: in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Study period:
- 16 Mar - 18 Mar 1993
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Remarks:
- The method is well-documented, but not yet validated. It is currently in use as an alternative to in vivo eye irritation studies for substances which are shown to be irritating in skin irritation tests.
- Principles of method if other than guideline:
- ex vivo rabbit eye irritation study
- GLP compliance:
- yes
- Remarks:
- Environmental Safety Laboratory, Unilever Research, Bedford UK.
- Species:
- rabbit
- Vehicle:
- unchanged (no vehicle)
- Controls:
- other: 2 untreated eyes served as control
- Amount / concentration applied:
- undiluted
Amount applied: 50 mg - Duration of treatment / exposure:
- 1 minute(s)
- Observation period (in vivo):
- eyes ex vivo were checked 0.5, 1, 2, 3, and 4 h after treatment for opacification of the cornea and corneal thickness
1 h after treatment fluorescein solution was applied and the rate of fluorescein diffusion into the corneal stroma was assessed togehter with possible corneal damage
4 h after treatment eyes were dissected and corneas underwent histological examination - Number of animals or in vitro replicates:
- 3 rabbit eyes (ex vivo) were treated with the test substance
2 control rabbit eyes (ex vivo) were untreated - Irritation parameter:
- cornea opacity score
- Run / experiment:
- 1 min treatment
- Value:
- 4
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: 4 = Complete corneal opacity, iris not discernible.
- Irritation parameter:
- percent corneal swelling
- Run / experiment:
- 1 min treatment
- Value:
- > 0 - < 100
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: No corneal swelling measurements were taken because of the considerable damage to the corneal surface.
- Irritation parameter:
- other: fluorescein staining
- Run / experiment:
- 1 min treatment
- Value:
- 4
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: 4 = Strong - Intense staining of the epithelium and anterior stroma with very rapid diffusion into the remainder of the stroma.
- Irritation parameter:
- histopathological observations
- Run / experiment:
- 1 min treatment
- Value:
- >= 1 - <= 7
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Loss of corneal cell layers: 1-7 (According to the study report, 8 epithelial cell layers are normal.)
- Interpretation of results:
- Category 1 (irreversible effects on the eye) based on GHS criteria
- Endpoint:
- eye irritation: in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Study period:
- 16 Mar - 18 Mar 1993
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Remarks:
- The method is well-documented, but not yet validated. It is currently in use as an alternative to in vivo eye irritation studies for substances which are shown to be irritating in skin irritation tests.
- Principles of method if other than guideline:
- ex vivo rabbit eye irritation study
- GLP compliance:
- yes
- Remarks:
- Environmental Safety Laboratory, Unilever Research, Bedford UK.
- Species:
- rabbit
- Details on test animals or tissues and environmental conditions:
- TEST ANIMALS:
- Source: Laboratories of Industrial Toxicology, Huntingdon Research Centre Ltd. (HRC)
The eyes were from animals used by HRC in skin irritation tests or were the control eyes from eye irritation tests. - Vehicle:
- unchanged (no vehicle)
- Controls:
- other: 2 untreated eyes served as control
- Amount / concentration applied:
- undiluted
Amount applied: 50 mg - Duration of treatment / exposure:
- 1 minute(s)
- Observation period (in vivo):
- eyes ex vivo were checked 0.5, 1, 2, 3, and 4 h after treatment for opacification of the cornea and corneal thickness
1 h after treatment fluorescein solution was applied and the rate of fluorescein diffusion into the corneal stroma was assessed togehter with possible corneal damage
4 h after treatment eyes were dissected and corneas underwent histological examination - Number of animals or in vitro replicates:
- 3 rabbit eyes (ex vivo) were treated with the test substance
2 control rabbit eyes (ex vivo) were untreated - Irritation parameter:
- cornea opacity score
- Run / experiment:
- 1 min treatment
- Value:
- 2
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: 2 = early discernable greyish transculant areas, details of iris slightly obscured
- Irritation parameter:
- percent corneal swelling
- Run / experiment:
- 1 min treatment
- Value:
- 28.25
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Timepoint of measurement and of maximum swelling after treatment: 240 min. Corneal swelling is expressed as the percentage increase in thickness compared with the pre-treatment thickness.
- Irritation parameter:
- other: fluorescein staining
- Run / experiment:
- 1 min treatment
- Value:
- 2
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Distinct - Pale continuous staining of the epithelium with slow diffusion into the stroma.
- Irritation parameter:
- histopathological observations
- Run / experiment:
- 1 min treatment
- Value:
- >= 1 - <= 7
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Loss of corneal cell layers: 1-7 (According to the study report, 8 epithelial cell layers are normal.)
- Interpretation of results:
- other: moderately irritating
- Endpoint:
- eye irritation: in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Study period:
- 16 Mar - 18 Mar 1993
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Remarks:
- The method is well-documented, but not yet validated. It is currently in use as an alternative to in vivo eye irritation studies for substances which are shown to be irritating in skin irritation tests.
- Principles of method if other than guideline:
- ex vivo rabbit eye irritation study
- GLP compliance:
- yes
- Remarks:
- Environmental Safety Laboratory, Unilever Research, Bedford UK.
- Species:
- rabbit
- Vehicle:
- unchanged (no vehicle)
- Controls:
- other: 2 enucleated eyes served as control
- Amount / concentration applied:
- undiluted
Amount applied: 50 mg - Duration of treatment / exposure:
- 1 minute(s)
- Observation period (in vivo):
- eyes ex vivo were checked 0.5, 1, 2, 3, and 4 h after treatment for opacification of the cornea and corneal thickness
1 h after treatment fluorescein solution was applied and the rate of fluorescein diffusion into the corneal stroma was assessed togehter with possible corneal damage
4 h after treatment eyes were dissected and corneas underwent histological examination - Number of animals or in vitro replicates:
- 3 rabbit eyes (ex vivo) were treated with the test substance
2 control rabbit eyes (ex vivo) were untreated - Irritation parameter:
- cornea opacity score
- Run / experiment:
- 1 min treatment
- Value:
- 4
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: 4 = Complete corneal opacity, iris not discernible.
- Irritation parameter:
- percent corneal swelling
- Run / experiment:
- 1 min treatment
- Value:
- > 0 - < 100
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: No corneal swelling measurements were taken because of the considerable damage to the corneal surface.
- Irritation parameter:
- other: fluorescein staining
- Run / experiment:
- 1 min treatment
- Value:
- 4
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: 4 = Strong - Intense staining of the epithelium and anterior stroma with very rapid diffusion into the remainder of the stroma.
- Irritation parameter:
- histopathological observations
- Run / experiment:
- 1 min treatment
- Value:
- >= 4 - <= 7
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Loss of corneal cell layers: 4-7 (According to the study report, 8 epithelial cell layers are normal.)
- Interpretation of results:
- Category 1 (irreversible effects on the eye) based on GHS criteria
- Endpoint:
- eye irritation: in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Study period:
- 16 Mar - 18 Mar 1993
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Remarks:
- The method is well-documented, but not yet validated. It is currently in use as an alternative to in vivo eye irritation studies for substances which are shown to be irritating in skin irritation tests.
- Principles of method if other than guideline:
- ex vivo rabbit eye irritation study
- GLP compliance:
- yes
- Remarks:
- Environmental Safety Laboratory, Unilever Research, Bedford UK.
- Species:
- rabbit
- Details on test animals or tissues and environmental conditions:
- TEST ANIMALS: - Source: Laboratories of Industrial Toxicology, Huntingdon Research Centre Ltd. (HRC)
The eyes were from animals used by HRC in skin irritation tests or were the control eyes from eye irritation tests. - Vehicle:
- unchanged (no vehicle)
- Controls:
- other: 2 untreated eyes served as control
- Amount / concentration applied:
- undiluted
Amount applied: 50 mg - Duration of treatment / exposure:
- 1 minute(s)
- Observation period (in vivo):
- eyes ex vivo were checked 0.5, 1, 2, 3, and 4 h after treatment for opacification of the cornea and corneal thickness
1 h after treatment fluorescein solution was applied and the rate of fluorescein diffusion into the corneal stroma was assessed togehter with possible corneal damage
4 h after treatment eyes were dissected and corneas underwent histological examination - Number of animals or in vitro replicates:
- 3 rabbit eyes (ex vivo) were treated with the test substance
2 control rabbit eyes (ex vivo) were untreated - Irritation parameter:
- cornea opacity score
- Run / experiment:
- 1 min treatment
- Value:
- ca. 2 - ca. 3
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: 2 = early discernable greyish transculant areas, details of iris slightly obscured; 3 = grey/ white areas, no details of iris visible, size of pupil barely discernible
- Irritation parameter:
- percent corneal swelling
- Run / experiment:
- 1 min treatment
- Value:
- 46.56
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Timepoint of measurement and of maximum swelling after treatment: 240 min. Corneal swelling is expressed as the percentage increase in thickness compared with the pre-treatment thickness.
- Irritation parameter:
- other: fluorescein staining
- Run / experiment:
- 1 min treatment
- Value:
- 2
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Distinct - Pale continuous staining of the epithelium with slow diffusion into the stroma.
- Irritation parameter:
- histopathological observations
- Run / experiment:
- 1 min treatment
- Value:
- >= 1 - <= 7
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Loss of corneal cell layers: 1-7 (According to the study report, 8 epithelial cell layers are normal.)
- Interpretation of results:
- other: irritating to the eye
- Endpoint:
- eye irritation: in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Study period:
- 16 Mar - 18 Mar 1993
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Remarks:
- The method is well-documented, but not yet validated. It is currently in use as an alternative to in vivo eye irritation studies for substances which are shown to be irritating in skin irritation tests.
- Principles of method if other than guideline:
- ex vivo rabbit eye irritation study
- GLP compliance:
- yes
- Remarks:
- Environmental Safety Laboratory, Unilever Research, Bedford UK.
- Species:
- rabbit
- Vehicle:
- unchanged (no vehicle)
- Controls:
- other: 2 enucleated eyes served as control
- Amount / concentration applied:
- undiluted
Amount applied: 50 mg - Duration of treatment / exposure:
- 1 minute(s)
- Observation period (in vivo):
- eyes ex vivo were checked 0.5, 1, 2, 3, and 4 h after treatment for opacification of the cornea and corneal thickness
1 h after treatment fluorescein solution was applied and the rate of fluorescein diffusion into the corneal stroma was assessed togehter with possible corneal damage
4 h after treatment eyes were dissected and corneas underwent histological examination - Number of animals or in vitro replicates:
- 3 rabbit eyes (ex vivo) were treated with the test substance
2 control rabbit eyes (ex vivo) were untreated - Irritation parameter:
- cornea opacity score
- Run / experiment:
- 1 min treatment
- Value:
- 1
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: 1 = scattered/diffuse areas of opacity or loss of corneal epithelium, iris clearly visible
- Irritation parameter:
- percent corneal swelling
- Run / experiment:
- 1 min treatment
- Value:
- 20.34
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Timepoint of measurement and of maximum swelling after treatment: 240 min. Corneal swelling is expressed as the percentage increase in thickness compared with the pre-treatment thickness.
- Irritation parameter:
- other: fluorescein staining
- Run / experiment:
- 1 min treatment
- Value:
- 1
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Marginal = Punctuate staining across cornea with some evidence of slight diffusion into cornea.
- Irritation parameter:
- histopathological observations
- Run / experiment:
- 1 min treatment
- Value:
- >= 0 - <= 4
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Loss of corneal cell layers: 0-4 (According to the study report, 8 epithelial cell layers are normal.)
- Interpretation of results:
- other: slight irritating potential observed
- Endpoint:
- eye irritation: in vitro / ex vivo
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Study period:
- 16 Mar - 18 Mar 1993
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Remarks:
- The method is well-documented, but not yet validated. It is currently in use as an alternative to in vivo eye irritation studies for substances which are shown to be irritating in skin irritation tests.
- Principles of method if other than guideline:
- ex vivo rabbit eye irritation study
- GLP compliance:
- yes
- Remarks:
- Environmental Safety Laboratory, Unilever Research, Bedford UK.
- Species:
- rabbit
- Details on test animals or tissues and environmental conditions:
- TEST ANIMALS:
- Source: Laboratories of Industrial Toxicology, Huntingdon Research Centre Ltd. (HRC) - Vehicle:
- unchanged (no vehicle)
- Controls:
- other: 2 enucleated eyes served as control
- Amount / concentration applied:
- undiluted
Amount applied: 50 mg - Duration of treatment / exposure:
- 1 minute(s)
- Observation period (in vivo):
- eyes ex vivo were checked 0.5, 1, 2, 3, and 4 h after treatment for opacification of the cornea and corneal thickness
1 h after treatment fluorescein solution was applied and the rate of fluorescein diffusion into the corneal stroma was assessed togehter with possible corneal damage
4 h after treatment eyes were dissected and corneas underwent histological examination - Number of animals or in vitro replicates:
- 3 rabbit eyes (ex vivo) were treated with the test substance
2 control rabbit eyes (ex vivo) were untreated - Irritation parameter:
- cornea opacity score
- Run / experiment:
- 1 min treatment
- Value:
- ca. 1 - ca. 2
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: 1 = scattered/diffuse areas of opacity or loss of corneal epithelium, iris clearly visible; 2 = early discernable greyish transculant areas, details of iris slightly obscured
- Irritation parameter:
- percent corneal swelling
- Run / experiment:
- 1 min treatment
- Value:
- 19.32
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Timepoint of measurement and of maximum swelling after treatment: 240 min. Corneal swelling is expressed as the percentage increase in thickness compared with the pre-treatment thickness.
- Irritation parameter:
- other: fluorescein staining
- Run / experiment:
- 1 min treatment
- Value:
- 1
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Marginal = Punctuate staining across cornea with some evidence of slight diffusion into cornea.
- Irritation parameter:
- histopathological observations
- Run / experiment:
- 1 min treatment
- Value:
- >= 0 - <= 4
- Vehicle controls validity:
- not applicable
- Negative controls validity:
- not applicable
- Positive controls validity:
- not applicable
- Remarks on result:
- other: Loss of corneal cell layers: 0-4 (According to the study report, 8 epithelial cell layers are normal.)
- Interpretation of results:
- other: slight irritating potential observed
Referenceopen allclose all
AVERAGE SCORE:
- Maximum opacity score:
10 seconds: 1-2 ((1): scattered/diffuse areas of opacity or
loss of corneal epithelium, iris clearly visible/ (2):
easily discernable greyish transculant areas, details of
iris slightly obscured)
60 seconds: 4 (complete corneal opacity, iris not discernable)
- Maximum mean swelling:
10 seconds: 23.26%
60 seconds: Not measurable
- Fluorescein staining:
10 seconds: distinct (pale continous staining of the
epithelium with slow diffusion into stroma)
60 seconds: strong (intense staining of the epithelium and
anterior stroma with very rapid diffusion into the remainder
of the stroma)
- Loss of corneal cell layers:
10 seconds: 3-7
60 seconds: 1-7
AVERAGE SCORE:
- Maximum opacity score:
10 seconds: 1 (scattered/diffuse areas of opacity or loss of
corneal epithelium, iris clearly visible)
60 seconds: 2 (easily discernable greyish translucant areas,
details of iris slightly obscured)
- Maximum mean swelling:
10 seconds: 9.30%
60 seconds: 28.25%
- Fluorescein staining:
10 seconds: marginal (punctate staining across cornea with
some evidence of slight diffusion into cornea)
60 seconds: Distinct (pale continuous staining of the
epithelium with slow diffucion into the stroma)
- Loss of corneal cell layers:
10 seconds: 0-2
60 seconds: 1-7
AVERAGE SCORE:
- Maximum opacity score:
10 seconds: 1 (scattered/diffuse areas of opacity or loss of
corneal epithelium, iris clearly visible)
60 seconds: 4 (complete corneal opacity, iris not discernable)
- Maximum mean swelling:
10 seconds: 15.91%
60 seconds: Not measurable
- Fluorescein staining:
10 seconds: marginal (punctate staining across cornea with
some evidence of slight diffusion into cornea)
60 seconds: strong (intense staining of the epithelium and
anterior stroma with very rapid diffusion into the remiander
of the stroma)
- Loss of corneal cell layers:
10 seconds: 2-4
60 seconds: 4-7
AVERAGE SCORE:
- Maximum opacity score:
10 seconds: 1 (scattered/diffuse areas of opacity or loss of
corneal epithelium, iris clearly visible)
60 seconds: 2/3 (easily discernable greyish transculant
areas, details of iris slightly obscured/grey-white areas,
no details of iris visible, size of pupil barely discernable)
- Maximum mean swelling:
10 seconds: 16.28%
60 seconds: 46.56%
- Fluorescein staining:
10 seconds: marginal (punctate staining across cornea with
some evidence of slight diffusion into cornea)
60 seconds: distinct (pale continuous staining of the
epithelium with slow diffusion into the stroma).
- Loss of layers:
10 seconds: 1-3
60 seconds: 1-7
AVERAGE SCORE:
- Maximum opacity score:
10 seconds: 1 (scattered/diffuse areas of opacity or loss of
corneal epithelium, iris clearly visible)
60 seconds: 1 (scattered/diffuse areas of opacity or loss of
corneal epithelium, iris clearly visible)
- Maximum mean swelling:
10 seconds: 6.82%
60 seconds: 20.34%
- Fluorescein staining:
10 seconds: marginal (punctate staining across cornea with
some evidence of slight diffusion into cornea)
60 seconds: marginal (punctate staining across cornea with
some evidence of slight diffusion into cornea)
- Loss of corneal cell layers:
10 seconds: 1-3
60 seconds: 0-4
AVERAGE SCORE:
- Maximum opacity score: 1/2 ((1)scattered/diffuse areas of
opacity or loss of corneal epithelium, iris clearly
visible/(2) early discernable greyish transculant areas,
details of iris slightly obscured)
- Maximum mean swelling: 19.32%
- Fluorescein staining: Marginal (punctate staining across
cornea with some evidence of slight diffusion into cornea)
- Loss of corneal cell layers: 0-4
Additional information
The degree of irritation caused in the studies, indicate that the irritation response is inversely correlated with the molar ratio of sodium silicate; a lower molar ratio SiO2: Na2O leads to a higher irritation score and vice versa. This correlation is superimposed by the concentration effect: lower concentrations will exhibit lower irritancy as compared to higher concentrations of the same molar ratio. The inverse correlation with molar ratio is demonstrated by the studies of Cuthbert and Carr (1985) where sodium silicates of comparable concentrations (38 - 41%) but different molar ratios were tested. Whereas ratios of 2.0 and 2.4 exhibited irritating properties, ratios of 2.8 and 3.3 were not irritating. The concentration effect becomes evident when the irritancy of identical molar ratios but different concentrations are compared. A sodium silicate of MR 2.4 is irritating at 40% and corrosive at 82% (Cuthbert and Carr 1985, Karlsson and Loden 1984).
Sodium silicate can be irritating to corrosive to the skin of rabbits, depending on the molar ratio and concentration. Any effects on the skin decrease with increasing molar ratio, superimposed by increasing irritancy with increasing concentrations.
Due to animal welfare, in vivo eye irritation studies were not conducted since the substance is irritating/corrosive to skin (5.3.1). A series of non-validated in vitro studies indicate the same inverse correlation between molar ratio and irritation that has been observed for skin irritation. The powders of varying molar ratios exhibited effects in enucleated rabbit eyes ranging from severely irritating (MR 2.0, 2.4 and 2.6) to slightly irritating (MR 2.8, 3.0 and 3.3).
Justification for classification or non-classification
DSD: Irritating to corrosive depending on the molar ratio/specific concentration limit.
CLP: Depending on the molar ratio: no classification to skin corrosin/irritation category 1B.
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