Isooctyl palmitate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

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

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.46 (In Vitro Skin Irritation: Reconstructed Human Epidermis Model Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Isooctyl palmitate

EC Number:

215-675-9

EC Name:

Isooctyl palmitate

Cas Number:

1341-38-4

Molecular formula:

C24H48O2

IUPAC Name:

6-methylheptyl hexadecanoate

Test material form:

liquid

Remarks:

a colourless liquid

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

other: not specified

Source strain:

not specified

Details on test system:

Specification
The test system is a commercially available EpiDermTM-Kit, procured by MatTek.
The EpiDermTM tissue consists of human-derived epidermal keratinocytes which have been cultured to form a multi-layered, highly differentiated model of the human epidermis. It consists of organized basal, spinous and granular layers, and a multi-layered stratum corneum containing intercellular lamellar lipid layers representing main
lipid classes analogous to those found in vivo. The EpiDermTM tissues are cultured on specially prepared cell culture inserts.
Origin
EpiDermTM tissues were procured from MatTek In Vitro Life Science Laboratories, Bratisla-va.
Designation of the kit: EPI-200-SCT
Day of delivery: 12. Feb. 2019
Batch no.: 28683

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

30 µL

Duration of treatment / exposure:

19 hours and 25 minutes

Duration of post-treatment incubation (if applicable):

24 hours

Number of replicates:

96-well-plate

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

mean

Value:

ca. 98.7

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Remarks:

2.7%

Other effects / acceptance of results:

The test item 1341-38-4 Isooctyl palmitate is considered as non- irritant to skin.
After the treatment, the mean value of relative tissue viability was reduced to 98.7%. This value is above the threshold for skin irritation (50%).
The optical density of the negative control was well within the required acceptability crite-rion of 0.8 ≤ mean OD ≤ 2.8.
The positive control has met the acceptance criterion too, for thus ensuring the validity of the test system.
Variation within replicates was within the accepted range for negative control, positive control and test item (required: ≤ 18%).
For these reasons, the result of the test is considered valid.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test item 1341-38-4 Isooctyl palmitate is considered non- irritant to skin in the Reconstructed human Epidermis (RhE) Test Method.

Executive summary:

One valid experiment was performed.

Three tissues of the human skin model EpiDerm^TMwere treated withthe test itemfor 60 minutes.

The test item was applied directly to each tissue and spread to match the tissue size (0.63 cm²; as indicated by the supplier).

DPBS-buffer was used as negative control and 5% SDS solution was used as positive control.

After treatment with the negative control, the mean absorbance value was within the required acceptability criterion of 0.8 ≤ mean OD ≤ 2.8, OD was 1.7.

The positive control showed clear irritating effects. The mean value of relative tissue viability was reduced to 2.7 % (required:£20%).

The variation within the tissue replicates of negative control, positive control and test item was acceptable (required: ≤ 18%).

 

After the treatment with the test item, the mean value of relative tissue viability was reduced to 98.7 %. This value is above the threshold for skin irritation potential (50%). Test items that induce values above the threshold of 50% are considered non- irritant to skin.