Pentatriacontan-18-one

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

11.1 Deviations from the Study Plan
The following deviation from the study plan was documented:
The pre-incubation time was 1 hour, instead of 18 ± 3 hours overnight. This can be seen as uncritical, because the pre-incubation time must be at least 1 hour (in consultation with the tissue supplier; MatTek In Vitro Life Science Laboratories).

The deviation was assessed and signed by the study director on 08. Oct. 2018.
11.2 Deviations from the Guideline
The following deviation from the guideline was documented:
The pre-incubation time was 1 hour, instead of 18- 24 hours. This can be seen as uncritical, because the pre-incubation time must be at least 1 hour (in consultation with the tissue supplier; MatTek In Vitro Life Science Laboratories).

The deviation was assessed and signed by the study director on 08. Oct. 2018

Deviations:

yes

Remarks:

see Version/ remarks

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Pentatriacontan-18-one

EC Number:

207-993-1

EC Name:

Pentatriacontan-18-one

Cas Number:

504-53-0

Molecular formula:

C35H70O

IUPAC Name:

pentatriacontan-18-one

Test material form:

solid

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Details on animal used as source of test system:

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.

Vehicle:

unchanged (no vehicle)

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

Tissue Amount
1 26.3 mg
2 25.5 mg
3 26.5 mg

Duration of treatment / exposure:

1 hour

Duration of post-treatment incubation (if applicable):

23 hours

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Mean

Value:

107.6

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

Designation Stearone Positive Control
% Tissue viability (tissue 1) 106.7% 4.1%
% Tissue viability (tissue 2) 110.6% 3.7%
% Tissue viability (tissue 3) 105.5% 3.3%
% Tissue viability (mean) 107.6% 3.7%
± SD of mean tissue viability (%) 2.7% 0.4%

Any other information on results incl. tables

  

  Skin Irritation Potential of the Test Item

The mean value of relative tissue viability of the test item was increased to 107.6% after the treatment. This value is above the threshold for skin irritation (50%). Therefore, the test item is considered as non-irritant to skin.

Validity criteria and results are stated in the following table:

Table 9.3-a     Validity

Criterion	Demanded	Found
Mean OD of negative control	≥ 0.8 and ≤ 2.8	1.6
Mean % tissue viability of positive control SDS	< 20% of negative control	3.7%
SD of mean viability of the tissue replicates (%)	≤ 18%	5.5% (negative control) 0.4% (positive control) 2.7% (test item)

 

All validity criteria were met.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test item Stearone is considered as non-irritant to skin.
After the treatment, the mean value of relative tissue viability was increased to 107.6%. This value is above the threshold for skin irritation (50%). negative control was well within the required acceptability criterion

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.

Executive summary:

One valid experiment was performed.

Three tissues of the human skin model EpiDerm^TMwere treated with the test item for 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 1.6. 

The positive control showed clear irritating effects. The mean value of relative tissue viability was reduced to 3.7% (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 increased to 107.6%. 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. 

 

 

Therefore, the test item Stearone is considered non-irritant to skin in the Reconstructed human Epidermis (RhE) Test Method.