Essential oil obtained from the leaves of Cymbopogon flexuosus, gramineae by distillation

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

24 October 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to OECD guideline 437 and under GLP conditions.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying Ocular Corrosives and Severe Irritants)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Cymbopogon flexuosus

IUPAC Name:

Cymbopogon flexuosus

Details on test material:

- Name of test material (as cited in study report): Cymbopogon flexuosus
- Physical state: Liquid (pale yellow)
- Analytical purity: Confidential information
- Lot/batch No.: Confidential information
- Expiration date of the lot/batch: Confidential information
- Storage condition of test material: Room temperature in the dark

Test animals / tissue source

Species:

other: Bovine

Strain:

other: not relevant

Details on test animals or tissues and environmental conditions:

TEST SYSTEM
- Source: Local abattoir
- Age at study initiation: 12-60 months

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied: 0.75 mL
- Concentration: 100%

Duration of treatment / exposure:

10 minutes (incubation at 32+/-1 °C)

Observation period (in vivo):

Not relevant

Number of animals or in vitro replicates:

Test substance: 3 corneas
Negative control: 3 corneas
Positive control: 3 corneas

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Time after start of exposure: 10 minutes

SCORING SYSTEM:
The In Vitro Irritancy Score was calculated as follows: mean opacity value + (15*OD492 value)
- Prediction model: IVIS≤3 = "No category. Not requiring classification to UN GHS or EU CLP", IVIS >3; ≤55 = "No prediction of eye irritation can be made", IVIS >55 = "Category 1. UN GHS or EU CLP Causes serious eye damage".
- The change in opacity for each cornea was calculated by subtracting the initial opacity reading from the final opacity reading. This value was corrected by subtracting the average change in opacity for the negative control. The average is used to calculate the IVIS.
- The corrected OD492 was calculated by substracting the OD492 of the negative control from the OD492 value of each treated cornea. The average is used to calculate the IVIS.

TOOL USED TO ASSESS SCORE:
- Opacity: Light transmision measured quantitatively with the aid of an opacitometer
- Permeability: After incubation of the cornea with sodium fluorescein for 90 minutes (anterior chamber), the concentration of this substance in the medium of the posterior chamber was determined using the Anthos 2001 microplate reader.

Results and discussion

In vivo

Irritant / corrosive response data:

- IVIS test item: 8.6
- IVIS negative control: 0.9
- IVIS positive control: 37.0

Other effects:

The corneas treated with test item were clear post treatment and cloudy post incubation. Corneas treated with negative control item were clear post treatment and incubation. Corneas of the positive control were cloudy post treatment and post-incubation.

Any other information on results incl. tables

The positive control IVIS score was within the range of 27.8 to 51.0. The negative control gave opacity of ≤4.7 and permeability ≤0.080. Both the positive and negative control acceptance criteria were therefore satisfied.

Applicant's summary and conclusion

Interpretation of results:

other: inconclusive

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of this study, the IVIS score for Cymbopogon flexuosus was determined to be 8.6. Based on this result, the study is considered inconclusive and no prediction of eye irritation or corrosion can be made.

Executive summary:

An in vitro Bovine Corneal Opacity and Permeability (BCOP) assay was performed with Cymbopogon flexuosus according to OECD guideline 437 and under GLP conditions. Bovine cornea were acquired on day of slaughter from a local abattoir, prepared and treated within 24 hours with the test substance, positive or negative control substance. In Vitro Irritancy Scores (IVIS) were calculated based on the measured opacity and permeability of the cornea after a 10 minutes exposure.

Under the conditions of this study, the IVIS score for Cymbopogon flexuosus was determined to be 8.6 which is above the threshold of 3 that indicates that the substance is not irritating. The score is also not above 55, representing the score that indicates serious eye damage. Therefore, the study result is considered inconclusive and no prediction of eye irritation or corrosion potential of Cymbopogon flexuoses can be made.