Dihydrogen wolframate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

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

Adequacy of study:

key study

Study period:

2002-07-01 to 2002-08-20

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Well documented, scientifically sound study that was conducted in accordance with GLP and OECD Guideline 405. The reliability of this study for the substance tested is a K1, but in application of read-across to a different substance, ECHA's guidance specifies that the score can be a maximum of a K2.

Justification for type of information:

Tungstic acid (WO3•H2O) is the hydrated form of tungsten trioxide (WO3). Based on Annex V, hydrates and water free forms (anhydrous) of compounds can be regarded as the same substance for registration purposes. Therefore, tungstic acid will be considered equivalent to WO3. For more details on the rationale, refer to the attached description of the read-across approach (Annex 3).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2002

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Tungsten trioxide

EC Number:

215-231-4

EC Name:

Tungsten trioxide

Cas Number:

1314-35-8

Molecular formula:

O3W

IUPAC Name:

trioxotungsten

Details on test material:

- Name of test material (as cited in study report): Tungsten oxide (WO3)
- Physical state: Yellow to greenish powder
- Analytical purity: 99.88%
- Purity test date: 2002-05-28
- Stability under test conditions: 5 years
- Storage condition of test material: Ambient temperature, dry
- Melting point: Approx. 1473 degrees C
- pH: 6.1 (aqueous suspension, 100 g/L)
- Solubility in water: < 10 mg/L WO3

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Charles River Wiga
- Weight at study initiation: 2.1-2.2 kg
- Housing: Individual caging in metal wire cages (79 cm x 59 cm bottom area, 38 cm height, with a wooden rest shelf, 15 cm x 59 cm)
- Diet (eg ad libitum): Altromin 2023 diet for rabbits, ad libitum. Hay- briquettes were offered additionally as a dietary supplement.
- Water (eg ad libitum): Tap water from an automatic water system, ad libitum
- Acclimation period: 5 days (one animal), 12 days (two other animals)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): average of 19.4 ⁰C
- Humidity (%): average of 66.7%
- Air changes (per hr): 12/hr
- Photoperiod (hrs dark / hrs light): 12 dark/12 light (6 am to 6 pm)

IN-LIFE DATES: From: 2002-07-01 To: 2002-07-12

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: The left eyes remained untreated and served as a control

Amount / concentration applied:

The approximate equivalent of 0.1 mL (~100 mg) of the test substance was administered per animal into the conjunctival sacs of the right eyes by gently pulling the lower lids away from the eyeballs for instillation. The eyes were held closed for about one second to prevent a loss of test substance.

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

3 females

Details on study design:

SCORING SYSTEM: Scoring scheme for ocular lesions- examined the whole eye, the corneae, irises, and conjunctivae

TOOL USED TO ASSESS SCORE: otoscope lamp

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

72 h

Score:

0

Remarks on result:

no indication of irritation

Remarks:

no eye lesions were observed in any animal

Results 2

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Remarks on result:

no indication of irritation

Results 3

Irritation parameter:

iris score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Remarks on result:

no indication of irritation

Results 4

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Remarks on result:

no indication of irritation

Results 5

Irritation parameter:

chemosis score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

Both the untreated eyes and the eyes treated with the test substance, for all three animals, were normal at each observation point.

Other effects:

No general toxic effects of the test substance were observed.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The administration of 100 mg of the test substance to the eyes of female rabbits, resulted in no signs of eye irritation. According to the Directive 2001/59/EC, the test substance is not "irritating to eyes."

Executive summary:

No eye irritation data are available for tungstic acid (target substance). However, eye irritation data are available for tungsten trioxide (source substance), which were used for read-across. Tungstic acid (WO3•H2O) is the hydrated form of tungsten trioxide (WO3). Based on Annex V, hydrates and water free forms (anhydrous) of compounds can be regarded as the same substance for registration purposes. Therefore, tungstic acid will be considered equivalent to WO3. For more details on the rationale, refer to the attached description of the read-across category approach.