Isobutyl methacrylate

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1980

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Federal Hazardous Substances Labeling Act Regulations, Section 191.12, Federal Register: 29, 13009 (1964)

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Isobutyl methacrylate

EC Number:

202-613-0

EC Name:

Isobutyl methacrylate

Cas Number:

97-86-9

Molecular formula:

C8H14O2

IUPAC Name:

isobutyl methacrylate

Specific details on test material used for the study:

Isobutyl methacrylate. Purity (99%) validated with  documentation from Atofina (December, 2001).

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

New Zealand White Rabbits, female, weighing 2-2.5 kg.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: Each animal served as its own control: the untreated eye was used to provide control information.

Amount / concentration applied:

undiluted
Amount applied: 0.1 ml

Duration of treatment / exposure:

72 hour(s)

Observation period (in vivo):

24, 48, 72 h

Number of animals or in vitro replicates:

6

Details on study design:

 Six NZ White rabbits were administered 0.1 ml (vol) of test  compound into the everted lower lid of one eye of 
each rabbit; eyelids  were closed and held shut for 1 second. Prior to administration the eyes  of each rabbit
 were examined. Eyes remained unwashed. Eyes scored at 24,  48 and 72 hrs after administration with the aid 
of an ophthalmoscope and  Fluorescin sodium.

Comment: not rinsed

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

animal: #1, #2, #3, #4, #5, #6,

Time point:

24/48/72 h

Score:

0

Max. score:

4

Results 2

Irritation parameter:

iris score

Basis:

animal: #1, #2, #3, #4, #5, #6

Time point:

24/48/72 h

Score:

0

Max. score:

2

Results 3

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

3

Reversibility:

not reversible

Remarks:

within 72 h

Results 4

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal: #2, #5

Time point:

24/48/72 h

Score:

1.33

Max. score:

3

Reversibility:

not reversible

Remarks:

within 72 h

Results 5

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #3

Time point:

24/48/72 h

Score:

1

Max. score:

3

Reversibility:

not reversible

Remarks:

within 72 h

Results 6

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #4

Time point:

24/48/72 h

Score:

0.66

Max. score:

3

Reversibility:

fully reversible within: 72 h

Results 7

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #6

Time point:

24/48/72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible

Remarks:

within 72 h

Results 8

Irritation parameter:

conjunctivae score

Remarks:

chemosis

Basis:

animal #1

Time point:

24/48/72 h

Score:

1.33

Max. score:

4

Reversibility:

not reversible

Remarks:

whithin 72 h

Results 9

Irritation parameter:

conjunctivae score

Remarks:

chemosis

Basis:

animal: #2, #3#, #4

Time point:

24/48/72 h

Score:

0.66

Max. score:

4

Reversibility:

fully reversible within: 72 h

Results 10

Irritation parameter:

conjunctivae score

Remarks:

chemosis

Basis:

animal: #5, #6

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritant / corrosive response data:

MEASURED ENDPOINT/INDEX (i.e. LD50, PII): PII = 1.67; scores were 2.17  (24 hr), 1.83 (48 hrs), and 1.0 (72 hrs).

RESULTS/OBSERVATIONS: Conjunctival irritation, redness (max. grade 2 in  3/6 rabbits) and chemosis (max. grade 2 
in 1/6 rabbits) at 24 hr.  Irritation (redness and chemosis), grade 2, was still present at 48 hr in  4/6 rabbits. At 72 hrs 
the irritation (redness) was grade 2 in 1/6,   grade 1 in 3/6; chemosis was grade 1 in 1/6 and 0 in 5/6 rabbits. There  
was no involvement of the cornea or the iris.

Any other information on results incl. tables

 

Animal No.	Corneal opacity/ Hornhauttrübung [Scores]			Mean Draize score	Reversibility [scores]		Hazard category
	after 24 h	after 48 h	after 72 h		in 7 days	in 21 days
1	0	0	0	0
2	0	0	0	0
3	0	0	0	0
4	0	0	0	0
5	0	0	0	0
6	0	0	0	0
							none
Animal No.	Iritis/ Regenbogenhautentzündung [Scores]			Mean Draize score	Reversibility [scores]		Hazard category
	after 24 h	after 48 h	after 72 h		in 7 days	in 21 days
1	0	0	0	0
2	0	0	0	0
3	0	0	0	0
4	0	0	0	0
5	0	0	0	0
6	0	0	0	0
							none

 

 

Animal No.	Conjunctiva redness (erythem) /Bindehautrötung [Scores]			Mean Draize score	Reversibility [scores]		Hazard category
	after 24 h	after 48 h	after 72 h		in 7 days	in 21 days
1	2	2	2	2.0
2	2	1	1	1.3
3	1	1	1	1.0
4	1	1	0	0.7
5	2	1	1	1.3
6	0	1	0	0.3
				1.1			none
Animal No.	Conjunctiva chemosis / Bindehautödem [Scores]			Mean Draize score	Reversibility [scores]		Hazard category
	after 24 h	after 48 h	after 72 h		in 7 days	in 21 days
1	2	1	1	1.3
2	1	1	0	0.7
3	1	1	0	0.7
4	1	1	0	0.7
5	0	0	0	0.0
6	0	0	0	0.0
				0.6			none

 

 

Classification: Hazard Category

none

Applicant's summary and conclusion

Interpretation of results:

slightly irritating

Remarks:

Migrated information Criteria used for interpretation of results: other: REGULATION (EC) No 1272/2008 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 16 December 2008

Conclusions:

Classification: not irritating

Executive summary:

In an occular irritation test acc. the federal Hazardous Substances and Labelling Act Regulations, Section 191.12 published in the Federal Register - 29 F.R. 13009, 1964. iso-butyl methacrylate (0.1 ml) was placed in the conjunctival sac of the right eye of six New Zealand White rabbits. The lids were then gently held together for one second.   The test eyes were not washed out following the instillation.   The left eye remained untreated for control.  The eyes were examined at 1, 24, 48 and 72 hours. Eye irritation was scored for signs of corneal damage (density, area), iris reaction and lesions of the conjunctivae (erythema, chemosis, discharge). Additionally, the cornea was examined with the aid of fluorescein after recording the observations at 24 hours. No observation after 72 hrs. No animal showed corneal damage or iritis (mean scores: 0). The highest conjunctiva score for redness was 1.33 in 2/6 animals and the highest conjunctiva score for chemosis was 1.33 in 1/6 animals. In summary iso-butyl methacrylate is considered as slightly irritating to eyes.