Hexanal

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018-03-01 to 2018-03-01

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 438 (Isolated Chicken Eye Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

OGYEI, Budapest (21.04.2016)

Test material

Test material information

Constituent 1

Reference substance name:

Hexanal

EC Number:

200-624-5

EC Name:

Hexanal

Cas Number:

66-25-1

Molecular formula:

C6H12O

IUPAC Name:

hexanal

impurity 1

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

Water

additive 1

Reference substance name:

3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-ol

EC Number:

233-466-0

EC Name:

3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-ol

Cas Number:

10191-41-0

Molecular formula:

C29H50O2

IUPAC Name:

2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)chroman-6-ol

Test material form:

liquid

Details on test material:

- State of aggregation: clear liquid

Test animals / tissue source

Species:

chicken

Strain:

other: ROSS 308

Details on test animals or tissues and environmental conditions:

SOURCE OF COLLECTED EYES
- Source: TARAVIS KFT. 9600 Sárvár, Rábasömjéni út 129. Hungary
- indication of any existing defects or lesions in ocular tissue samples: the selected eyes were examined with the slit lamp microscope to ensure that they were in good condition. The focus was adjusted to see clearly the isotonic saline which was flowing on the cornea surface. Eyes with a high baseline fluorescein staining (i.e., > 0.5) or corneal opacity score (i.e., > 0.5) were rejected.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

30 µL

Duration of treatment / exposure:

10 seconds exposure

Duration of post- treatment incubation (in vitro):

up to 240 minutes after the post-treatment rinse

Number of animals or in vitro replicates:

3

Details on study design:

SELECTION AND PREPARATION OF ISOLATED EYES : The eyeball was carefully removed from the orbit by holding the nictitating membrane with surgical forceps, while cutting the eye muscles with bent scissors. Care was taken to remove the eyeball from the orbit without cutting off the optical nerve too short. The procedure avoided pressure on the eye while removing the eyeball from the orbit, in order to prevent distortion of the cornea and subsequent corneal opacity. Once removed from the orbit, the eye was placed onto damp paper and the nictitating membrane was cut away with other connective tissue. The prepared eyes were kept on the wet papers in a closed box so that the appropriate humidity was maintained.

EQUILIBRATION AND BASELINE RECORDINGS : At the end of the acclimatization period, a zero reference measurement was recorded for cornea thickness and opacity to serve as a baseline (t=0) for each individual eye. The cornea thickness of the eyes should not change by more than ±5-7 % within approximately 45 to 60 minutes before the start of application. Slight changes in thickness (0 % to 2 %) were observed in the eyes, finding considered as normal when maintaining enucleated eyes. Following the equilibration period, the fluorescein retention was measured. Baseline values were required to evaluate any potential test item related effects after treatment. The location of any minor findings was marked on the record sheet as a drawing, if applicable. If any eye was considered to be unsuitable following baseline assessment, it was discarded.

NUMBER OF REPLICATES : test item: 3, positive control: 3, negative control: 1

NEGATIVE CONTROL USED : NaCl, 9 g/L saline

POSITIVE CONTROL USED: Acetic acid, 10 % (v/v)

APPLICATION DOSE AND EXPOSURE TIME : 30 µl, 10 seconds exposure

OBSERVATION PERIOD : 240 min

REMOVAL OF TEST SUBSTANCE
- Volume and washing procedure after exposure period: 20 ml saline solution


SCORING SYSTEM:
- Mean corneal swelling (%)
- Mean maximum opacity score
- Mean fluorescein retention score at 30 minutes post-treatment

DECISION CRITERIA: decision criteria as indicated in the TG were used.

Results and discussion

In vitro

Results

Results 1

Irritation parameter:

percent corneal swelling

Value:

>= 14 - <= 18

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation parameter:

cornea opacity score

Value:

1.7

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 3

Irritation parameter:

fluorescein retention score

Value:

0.5

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Results 4

Irritation parameter:

other: overall ICE Class

Remarks on result:

other: 1x I, 2x III

Any other information on results incl. tables

Test Item: Hexanal

 

Observation	Value	ICE Class
Mean maximum corneal swelling at up to 75 min	14 %	III
Mean maximum corneal swelling at up to 240 min	18 %	II
Mean maximum corneal opacity	1.7	III
Mean fluorescein retention	0.5	I
Other Observations	None
Overall ICE Class	1xI, 2xIII

Applicant's summary and conclusion

Interpretation of results:

other:

Remarks:

Not ocular corrosive (not Cat. 1). The assay does not allow a conclusion regarding ocular irritation (Cat. 2)

Conclusions:

In this ICET, hexanal did not cause ocular corrosion or severe irritation in the enucleated chicken eye. The overall ICE score was 1xI, 2xIII.
Positive and negative controls showed the expected results. The experiment was considered to be valid.

Executive summary:

The severe eye irritation potential of the test item hexanal was analysed in an Isolated Chicken Eye Test (ICET) according to OECD TG 438 under GLP conditions. Isolated chicken eyes were exposed to 30 µL of undiluted hexanal for 10 seconds, followed by a post-treatment observation period of up to 240 min. In this ICET, hexanal did not cause ocular corrosion or severe irritation in the enucleated chicken eyes. The overall ICE score was 1xI, 2xIII. Positive and negative controls showed the expected results. The experiment was considered to be valid.

According to the OECD TG 438, the overall classification of hexanal is neither UN GHS Category I (an ocular corrosive or severe eye irritant) nor No Category.