Ashes (residues), rice husk

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 Apr 2010 - 23 Apr 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Bayerisches Landesamt für Gesundheit und Lebensmittelsicherheit, Landesinstitut für Arbeitsschutz und Produktsicherheit, Munich, Germany

Test material

Test material information

Constituent 1

Reference substance name:

Ashes (residues), rice husk

EC Number:

275-735-5

EC Name:

Ashes (residues), rice husk

Cas Number:

71630-92-7

Molecular formula:

SiO2

IUPAC Name:

silanedione

Details on test material:

- Name of test material (as cited in study report): Rice husk ashes
- Physical state: crystalline black powder
- Analytical purity: >80%
- Storage condition of test material: room temperature

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, D-97633 Sulzfeld
- Age at study initiation: approximately 28 weeks
- Weight at study initiation: > 2 kg
- Housing: ABS - plastic rabbit cages, floor 4200 cm2
- Diet (e.g. ad libitum): autoclaved hay and Altromin 2123 maintenance diet for rabbits (lot no. 0748), rich in erude fibre; ad libitum
- Water (e.g. ad libitum): tap water (drinking water, municipal residue control, microbiol. controlled periodically); ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 ± 3
- Humidity (%): 55 ± 10
- Air changes (per hr): at least 10
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: The untreated contralateral eye served as control.

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 g

Duration of treatment / exposure:

24 h

Observation period (in vivo):

72 h

Number of animals or in vitro replicates:

3

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): the treated eye was rinsed with physiological sahne 0.9% NaCl .
- Time after start of exposure: 24 h

SCORING SYSTEM: Draize scores

TOOL USED TO ASSESS SCORE: fluorescein

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

other: mean over 24, 48, 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Results 2

Irritation parameter:

iris score

Basis:

animal #1

Time point:

other: mean over 24, 48, 72 h

Score:

0

Max. score:

2

Reversibility:

other: not applicable

Results 3

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

other: mean over 24, 48, 72 h

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 h

Results 4

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

other: mean over 24, 48, 72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 h

Results 5

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

other: mean over 24, 48, 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Results 6

Irritation parameter:

iris score

Basis:

animal #2

Time point:

other: mean over 24, 48, 72 h

Score:

0

Max. score:

2

Reversibility:

other: not applicable

Results 7

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

other: mean over 24, 48, 72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 h

Results 8

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

other: mean over 24, 48, 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Results 9

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

other: mean over 24, 48, 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Results 10

Irritation parameter:

iris score

Basis:

animal #3

Time point:

other: mean over 24, 48, 72 h

Score:

0

Max. score:

2

Reversibility:

other: not applicable

Results 11

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

other: mean over 24, 48, 72 h

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 h

Results 12

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

other: mean over 24, 48, 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritant / corrosive response data:

The test item produced slight irritant but reversible effects after instillation into the eyes of 3 female rabbits (strain NZW) (Tables 1 to 3).
Upon fluorescein examinations at the end of the observation period of 72 hours no corneal lesions were found in any animal.
Conjunctival discharge was observed 1 hour post-instillation in all test animals, which was reversible within 24 hours.
Conjunctival redness and chemosis were also observed in all test animals, and are described individually in Tables no. 1, 2 and 3.

Other effects:

Neither mortalities nor significant clinical signs of toxicity were observed (Table 4).

Any other information on results incl. tables

Table 1: Eye Irritation Scores — Animal No. 1

 

Animal No. 1		Individual Data				Average Score (24, 48 and 72 hours)
		Time Post Application
		1 h	24 h	48 h	72 h
		T/C	T/C	T/C	T/C
	Cornea	0/0	0/0	0/0	0/0	0
	Iris	0/0	0/0	0/0	0/0	0
	ConjunctivalRedness	1/0	1/0	1/0	0/0	0.67
	ConjunctivalChemosis	2/0	1/0	0/0	0/0	0.33

 

T =test item, C = control

 

Table 2: Eye Irritation Scores — Animal No, 2

 

Animal No. 2		Individual Data				Average Score (24, 48 and 72 hours)
		Time Post Application
		1 h	24 h	48 h	72 h
		T/C	T/C	T/C	T/C
	Cornea	0/0	0/0	0/0	0/0	0
	Iris	0/0	0/0	0/0	0/0	0
	ConjunctivalRedness	1/0	1/0	0/0	0/0	0.33
	ConjunctivalChemosis	1/0	0/0	0/0	0/0	0

 

T = test item, C = control

Table 3: Eye Irritation Scores — Animal No. 3

 

Aninial No. 3		Individual Data				Average Score (24, 48 and 72 hours)
		Time Post Application
		1 h	24 h	48 h	72 h
		T/C	T/C	T/C	T/C
	Cornea	0/0	0/0	0/0	0/0	0
	Iris	0/0	0/0	0/0	0/0	0
	ConjunctivalRedness	1/0	1/0	1/0	0/0	0.67
	ConjunctivalChemosis	1/0	0/0	0/0	0/0	0

 

T = test item, C = control

 

Table 4: Individual Data

Individual.Systemic and Local Findings
Time after Test Item Application	Animal Number 1			Animal,Number 2			Animal Number 3
	systemic Findings	Specific LocalFindings	Com-ments	Systemic Findings	Specific LocalFindings	Com-ments	Systemic Findings	Specific LocalFindings	Com-ments
1 h	nsf	nsf	-	nsf	nsf	-	nsf	nsf	-
24 h	nsf	nsf	-	nsf	nsf	-	nsf	nsf	-
48 h	nsf	nsf	-	nsf	nsf	-	nsf	nsf	-
72 h	nsf	nsf	-	nsf	nsf	-	nsf	nsf	-
nsf = no specific findings

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of the present study, single ocular instillation of the test item Rice husk ash to rabbits at a dose of 0.1 g produced slight irritant effects, which were fully reversible within 72 hours. Neither mortalities nor significant clinical signs of toxicity were observed.
In conformity with the EC criteria for classification and labelling requirements for dangerous substances and preparations according to Annex VI of Commission Directive 2001/59/EC and Annex I of Regulation (EC) 1272/2008, the test item Rice husk ash does not have to be classified and has no obligatory labelling requirement for eye irritation.