Hydrocarbons, C5, n-alkanes, isoalkanes

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

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

Adequacy of study:

key study

Study period:

1996-07-30 to 1996-08-02

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

This study is classified as reliable without restriction because it is in compliance with OECD principles of GLP and the E.U. Council Decision on GLP.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

yes

Remarks:

Protocol deviations were minor and were not expected to interfere with the overall study results. Test report did not provide rationale for in vivo testing. Test report did not provide analysis for the stability, identity, strength, purity, composition.

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EC Dangerous Substances Directive (67/548/EEC), Methods of Determination of Toxicity, Annex V, Part B.5

Deviations:

yes

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: Animal Welfare Act (1966)

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Guide for the Care and Use of laboratory Animals (1985) DHHS

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Pentane

EC Number:

203-692-4

EC Name:

Pentane

Cas Number:

109-66-0

Molecular formula:

C5H12

IUPAC Name:

pentane

Details on test material:

- Name of test material (as cited in study report): n-pentane
- Substance type: C5 aliphatic
- Physical state: liquid
- Purity, stability, strenght, identity, and composition: Analysis was performed, but not provided in study report.
- Expiration date of the lot/batch: June 2001
-Storage condition of test material: refrigerated
-Supplier: Exxon Chemical, Belgium

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: HPR Inc., Denver, Pennsylvania
- Age at study initiation: Approximately 12 to 13 weeks
- Weight at study initiation: 2.29 to 2.34 kg
- Housing: Each animal was kept in a separate suspended stainless steel and wire mesh cage with absorbent paper.
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: lasted 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 to 21 °C
- Humidity (%): 40 to 60% relative humidity
- Photoperiod (hrs dark / hrs light): 12 hours light and 12 hours dark

IN-LIFE DATES: From: 1996-07-30 To: 1996-08-02

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: The contralateral eye on each animal served as the control.

Amount / concentration applied:

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

Duration of treatment / exposure:

Animals were exposed to 0.1 ml of the test material once over a 72-hour period.

Observation period (in vivo):

Observations were made at approximately 1, 24, 48, and 72 hours post-application.

Number of animals or in vitro replicates:

3 males

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The treated eyes of the 3 test animals remained unwashed.

SCORING SYSTEM: The Draize Standard Eye Irritation Grading Scale (Draize, 1959) was used for scoring. Animals were examined and scored using the naked eye begining at each 24 hour interval.

TOOL USED TO ASSESS SCORE: Two percent fluorescein dye was used under UV light to aid in examination and scoring.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

other: Redness

Basis:

mean

Time point:

other: 1 hour

Score:

2.33

Max. score:

110

Reversibility:

fully reversible within: 72 hours

Results 2

Irritation parameter:

other: Redness

Basis:

mean

Time point:

other: 24 hour

Score:

1.33

Max. score:

110

Reversibility:

fully reversible within: 72 hours

Results 3

Irritation parameter:

other: Redness

Basis:

mean

Time point:

other: 48 hour

Score:

0.33

Max. score:

110

Reversibility:

fully reversible within: 72 hours

Results 4

Irritation parameter:

chemosis score

Basis:

mean

Time point:

other: 1 hour

Score:

0.33

Max. score:

110

Reversibility:

fully reversible within: 72 hours

Irritant / corrosive response data:

Some degree of occular irritation of the conjunctiva was observed in all three animals. Redness was observed in all animals at the 1 and 24 hour observation points. Only for rabbit number JEK361M did redness persisted through to the 48 hour timepoint; chemosis and discharge were also observed in this animal at the 1 hour interval. No irritation was observed for any other irritation parameter or time point for the remaining two animals. No conjunctival irritation was observed at 72 hours for any test organism. n-Pentane was observed to be fully reversible within 72 hours.

Other effects:

Clinical signs were not observed in any animal and all animals survived until study termination.

Any other information on results incl. tables

	1 hour	24 hour	48 hour	72 hour
Redness	2.33	1.33	0.33	0.00
Chemosis	0.33	0.00	0.00	0.00
Iris	0.00	0.00	0.00	0.00
Opacity	0.00	0.00	0.00	0.00

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: OECD GHS

Conclusions:

Ocular exposure to 0.1 ml of n-pentane caused reversable irritation to the conjunctiva, but no iridial or corneal responses in any of the rabbits. Any sign of occular irritation was cleared in all test animals by the 72 hour interval.

Executive summary:

n-Pentane was tested for ocular irritation in 3 New Zealand White rabbits at a single 0.1 ml dose. Observations were made at 1, 24, 48, and 72 hours after application for indications of ocular irritation. Reactions were scored based on the Draize Standard Eye Irritation Grading Scale (Draize, 1959). N-pentane caused ocular irritation of the conjunctiva in all three test animals. All animals showed signs of redness at 1 hour and 24 hours after the installation. In only one animal did redness persist until the 48 hour observation period; this same animal was the only one to exhibit chemosis and discharge responses (at the 1 hour interval). All 3 animals were cleared of any ocular irritation at the 72 hour observation.

This study received a Klimish score of 1, reliable without restriction, because it is in compliance with OECD principles of GLP and the E.U. Council Decision on GLP.