[(3,7-dimethyl-6-octenyl)oxy]acetaldehyde

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From September 23, 2019 to December 19, 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

[(3,7-dimethyl-6-octenyl)oxy]acetaldehyde

EC Number:

231-324-2

EC Name:

[(3,7-dimethyl-6-octenyl)oxy]acetaldehyde

Cas Number:

7492-67-3

Molecular formula:

C12H22O2

IUPAC Name:

2-[(3,7-dimethyloct-6-en-1-yl)oxy]acetaldehyde

Test material form:

liquid

Specific details on test material used for the study:

Batch: VE00601569
Expiration date of the batch:
January 12, 2020
Physical Description: liquid colorless to pale yellow
Purity: 92.9%

In vitro test system

Test system:

human skin model

Remarks:

The EpiDerm Model (EPI-200)

Source species:

human

Cell type:

non-transformed keratinocytes

Vehicle:

unchanged (no vehicle)

Details on test system:

The EpiDerm Model (EPI-200) (MatTek Corporation, Ashland, USA) consists of normal, human-derived epidermal keratinocytes which have been cultured to form a multilayered, highly differentiated model of the human epidermis. It consists of organized basal, spinous and granular layers, and a multilayered stratum corneum containing intercellular lamellar lipud layers arranged in patterns analogous to those found in vivo.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

The test item was used as supplied, no vehicle used.
Positive Control: 5% (w/v)

Duration of treatment / exposure:

The test article, the positive control, and the negative control were treated in triplicate EpiDermTM tissues for a 60 ± 1 minute exposure period.

Duration of post-treatment incubation (if applicable):

42 ± 2-hour post-exposure incubation period.

Number of replicates:

Negative control: 3
Positive control: 3
Test item: 3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Remarks:

Mean of OD: 0.097

Value:

5.78

Vehicle controls validity:

not examined

Negative controls validity:

valid

Remarks:

Mean of viability: 100%, Mean of OD: 1.673, CV: 2.94%

Positive controls validity:

valid

Remarks:

Mean of viability: 2.52%, Mean of OD: 0.042, CV:4.74%

Remarks on result:

positive indication of irritation

Other effects / acceptance of results:

The assay was accepted when the following criteria were met: 1) the positive control (5% SDS) resulted in a mean tissue viability ≤ 20%, 2) the mean OD570 value of the negative control tissues was ≥ 0.8 and < 2.8, and 3) the standard deviations of the positive and negative control calculated from individual percent tissue viabilities of the three identically treated replicates were < 18%.

Any other information on results incl. tables

The skin irritancy potential of the test article was evaluated as described in OECD TG 439

In VitroResult	GHS Category
mean tissue viability ≤ 50%	Category 1 or 2*
mean tissue viability > 50%	No Category

* - Additional testing would be warranted to resolve between GHS Category 1 (Severe/Corrosive) and GHS Category 2 (Irritant)

Test results:

Test Article Number	Sponsor’s Designation	Conc. (w/v)	pH	Mean Viability (%)	Skin Irritation Prediction
19AH70	CITRONELLYL OXYACETALDEHYDE	Neat	5.0	5.78	Irritant
Positive Control	SDS	5%	NA	2.52	Irritant

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The mean tissue viability of the test substance, CITRONELLYL OXYACETALDEHYDE, was 5.78%. According to the prediction model presented in OECD TG 439, the test substance was predicted to be an irritant. Additional testing would be needed to determine if the test substance was a GHS Category 1 (Severe/Corrosive) or GHS Category 2 (Irritant) for skin irritation.

Executive summary:

The EpiDerm™ Skin Model (MatTek Corporation, MA, USA) was used to assess the potential dermal irritation of the test article. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) conversion assay, which measures the NAD(P)H-dependent microsomal enzyme reduction of MTT (and to a lesser extent, the succinate dehydrogenase reduction of MTT) to a blue formazan precipitate, was used to assess cellular metabolism after exposure to a test article. The protocol was based upon the OECD test guideline, “In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method” (TG 439).

The mean tissue viability of the test substance, CITRONELLYL OXYACETALDEHYDE, was 5.78%. According to the prediction model presented in OECD TG 439, the test substance was predicted to be an irritant. Additional testing would be needed to determine if the test substance was a GHS Category 1 (Severe/Corrosive) or GHS Category 2 (Irritant) for skin irritation.