Citronellyl formate

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

26 April 2017 - 30 June 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)

Version / remarks:

2016

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: B.40 bis (In Vitro Skin Corrosion: Human Skin Model Test)

Version / remarks:

2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Citronellyl formate

EC Number:

203-338-9

EC Name:

Citronellyl formate

Cas Number:

105-85-1

Molecular formula:

C11H20O2

IUPAC Name:

3,7-dimethyloct-6-en-1-yl formate

In vitro test system

Test system:

human skin model

Source species:

other: EpiDermTM Kit

Cell type:

non-transformed keratinocytes

Details on animal used as source of test system:

Epi-200 kits and MTT-100 assays were purchased from MatTek Corporation (Bratislava, Slovakia). EpiDerm™ tissues were shipped at 4 °C on medium-supplemented agarose gels in a 24-well plate. On day of receipt the pre-incubation phase of the EpiDerm™ tissues started.

Justification for test system used:

The EpiDermTM is an in vitro system recommended by the corresponding guideline.

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: Epi-200 Kit
- Tissue batch number: 25811
- Date of initiation of testing: 2017-05-10

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37 °C for 3 minutes; room temperature for 60 minutes

REMOVAL OF TEST MATERIAL AND CONTROLS
- Number of washing steps: 20 times
- Observable damage in the tissue due to washing: none

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 1mg/mL
- Incubation time: 3 h
- Spectrophotometer: Versamax Molecular Devices, Softmax Pro
- Wavelength: 570 nm

NUMBER OF REPLICATE TISSUES: 2

NUMBER OF INDEPENDENT TEST SEQUENCES / EXPERIMENTS TO DERIVE FINAL PREDICTION: 1

PREDICTION MODEL / DECISION CRITERIA
The test substance is considered to be corrosive to skin if:
- < 50% after 3 minutes exposure
- ≥ 50% after 3 minutes exposure AND < 15% after 60 minutes exposure
The test substance is considered to be non-corrosive to skin if:
- ≥ 50% after 3 minutes exposure AND ≥ 15% after 60 minutes exposure

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount applied: 50 µL

Duration of treatment / exposure:

3 min and 60 min

Number of replicates:

2

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

other: Relative Absorbance (% of Negative Control)

Run / experiment:

1_Exposure: 3 min

Value:

103.9

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

other: Relative Absorbance (% of Negative Control)

Run / experiment:

2_Exposure: 3 min

Value:

107.6

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Results 3

Irritation / corrosion parameter:

other: Relative Absorbance (% of Negative Control)

Run / experiment:

1_Exposure: 1 h

Value:

123.4

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Results 4

Irritation / corrosion parameter:

other: Relative Absorbance (% of Negative Control)

Run / experiment:

2_Exposure: 1h

Value:

126.5

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

OTHER EFFECTS:
- Visible damage on test system: none
- Direct-MTT reduction: none
- Colour interference with MTT: none

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes
- Acceptance criteria met for positive control: yes
- Acceptance criteria met for variability between replicate measurements: yes

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test item is non corrosive to skin according to EU CLP and UN GHS.

Executive summary:

An in vitro study was performed to assess the corrosive potential of the test item by means of the Human Skin Model Test with EpiDerm™ tissues models.

The test item passed the pre-test for colour interference and for direct MTT reduction. Consequently, additional tests were not necessary.

Independent duplicate tissues of EpiDerm™ were exposed to either the test item, the negative control (deionised water) or the positive control (8.0 N KOH) for 3 minutes and 1 hour, respectively. After exposure of the tissues to the test item the relative absorbance value did not decrease (105.7%) after 3 minutes exposure. After 1 hour exposure the relative absorbance value was also not reduced (124.9%). Both values did not affect the threshold for corrosiveness which is defined to be 50% after the 3 minutes exposure and 15% after the 1 hour exposure. The required acceptability criteria were met. The test item is not considered to be corrosive.