Diethylbenzene

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1987

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This is a GLP guideline study.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1987

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EPA OPP 81-4 (Acute Eye Irritation)

Deviations:

no

Remarks:

Not specified in report.

Principles of method if other than guideline:

Npt applicable

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Diethylbenzene

EC Number:

246-874-9

EC Name:

Diethylbenzene

Cas Number:

25340-17-4

Molecular formula:

C10H14

IUPAC Name:

diethylbenzene

Details on test material:

IUCLID4 Test substance: as prescribed by 1.1 - 1.4

MCS 2313; Diethylbenzene
Supplier: Monsanto
Reference No.: Lot/batch No. MBP 3494320
Appearance: Clear, colorless liquid

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

Source: New Zealand white rabbit; Summit View Farms, Hazleton, Pennsylvania

At start of the experiment, animals were at least 8 weeks old.  

Equilibration period: 20 days

Observations : All animals were checked for viability twice daily. Prior to assignment to study all animals were examined to ascertain suitability for study.

Husbandry: Currently acceptable practices of good animal husbandry were followed, e.g. Guide for the Care and Use of Latoratory Animals: DHEW Publication No. (NIH) 78-23 Revised 1978

Housing: Individually housed during study.

Cages: Suspended, stainless steel

Environmental Conditions: Temperature: 60-70F is considered an acceptable tmperature range for rabbits; room temperature was monitored and recorded twice daily and maintained within this range to the maximum extent possible.

Humidity: 30-70% is considered an acceptable humidity range for rabbits; room humidity was monitored and recorded daily and maintained within this range to the maximum extent possible.

Light Cycle: 12 hours light, 12 hours dark (controlled by a n automatic timer).

Food:Lab Rabbit Chow HF, (Purina #5326), ad libittum

Water: Automatic watering system, ad libitum. Municipal water supply (Elizabethtown Water Co.)

Contaminants: There were no known contaminants reasonably expected to be found in food or water which would interfere with the results of this study.

Identification: Each animal was identified with a monel eat tag, bearing a unique number, prior to testing.

Selection: Animals were randomly placed in cages upon receipt, and were placed on study as available at the time of study initiation. Any animals considered unsuitable because of poor health or ocular abnormalities were excluded from selection.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.1 ml

Duration of treatment / exposure:

single dose

Observation period (in vivo):

3-7 days

Number of animals or in vitro replicates:

6 (3/sex)

Details on study design:

Duration of Study:
A single dose w as admlnlstered followed by a 3 to 7 day observation period.

Route of Administration : Ocular
Justification for Route of Adnlnlstratlon: The study was intended to provide information on the health hazards likely to arise from a short-term accidental exposure to the test material by the ocular route.

Preparation of Animals:
On the dry before doslng, both eyes of each animal were examined usilng fluorescein dye to check for presence of cornerl ulceration. Just
prlor to test substance application, the eyes were examined again, but without fluorescein. Animals showing pre-existing corneal or
conjunctival injury or irritation were not placed on study.

Preparation of Test Material: The test material was administered as received; no mixture was required.

Administration of Test Substance:
The appropriate amount of the test material was introduced into the lower conjunctivall sac of the right eye of each animal. The upper and lower lids were gently held together for one second prlor to releasing to prevent loss of material. The contralateral eye served as the control.

Wash:
No wash was performed after application of the material. However, approximately 24 hrs after application, the treated eyes were rinsed to remove any residual test material.

Viability Checks:
Twice daily

Evaluation of Ocular Irritation:
1. Intervals
Approximately 1, 24, 48 and 72 hours and 7 days after treatment or until no signs of irritation were present.

2. Methods
At each interval the treated and control eyes were examined and scored for ocular reactions according to the Draize scale. Fluorescein dye was used to confirm presence or absence of corneal ulceration in treated eyes starting with the 24 hour observation and at each subsequent observation until there was no stain retention for two observations.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

conjunctivae score

Remarks:

Redness

Basis:

mean

Remarks:

over 6 rabbits

Time point:

24/48/72 h

Score:

1.3

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 2

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

over 6 rabbits

Time point:

24/48/72 h

Score:

0.2

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 3

Irritation parameter:

conjunctivae score

Remarks:

Discharge

Basis:

mean

Remarks:

over 6 rabbits

Time point:

24/48/72 h

Score:

0.7

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 4

Irritation parameter:

iris score

Basis:

mean

Remarks:

over 6 rabbits

Time point:

24/48/72 h

Score:

0

Max. score:

2

Results 5

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

over 6 aniumals

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritant / corrosive response data:

Produced mild but reversible ocular irritation.  Irritation consisted  primarily of conjuctival irritation (redness, chemosis, discharge) and  iridial changes.  No corneal changes were seen.  All six animals were  free of ocular irritation within 3 to 7 days after instillation of the  test material

Other effects:

None

Any other information on results incl. tables

Tissue	Endpoint	24, 48, 72 h scores mean						MEAN SCORE
		Animal No
		2781	2782	2783	2788	2791	2792
Conjuctiva	Redness	1.3	1	1.3	1.7	1.7	1	1.3
	Chemosis	0.3	0	0.3	0	0.3	0	0.2
	discharge	0.6	1	0.6	1	0.6	0.3	0.7
	necrosis	0	0	0	0	0	0	0
Iris		0	0	0	0	0	0	0
Cornea	Opacity	0	0	0	0	0	0	0
	area	0	0	0	0	0	0	0
	stippling	0	0	0	0	0	0	0
	ulceration	0	0	0	0	0	0	0

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information not classifiable Criteria used for interpretation of results: EU

Conclusions:

Produced mild but reversible ocular irritation.  Irritation consisted  primarily of conjuctival irritation (redness, chemosis, discharge) and  iridial changes.  No corneal changes were seen.  All six animals were  free of ocular irritation within 3 to 7 days after instillation of the  test material. BAsed on the results of this study, no classification for eye irritation would be necessary.

Executive summary:

This study was conducted for the Monsanto Company to evaluate the ocular irritation produced by MCS 2313 in rabbits. The eyes of six rabbits were instilled with undiluted test material and left unwashed. Ocular observations for irritancy were evaluated at ~1, 24, 48 and 72 hours and 7 days after treatment or until no signs of irritation wre present.

MCS2313 produced mild but reversible ocular irritation.  Irritation consisted  primarily of conjuctival irritation (redness, chemosis, discharge) and  iridial changes. 

 No corneal changes were seen.  All six animals were  free of ocular irritation within 3 to 7 days after instillation of the  test material.