Registration Dossier

Administrative data

Endpoint:
skin irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2016-12-23 - 2017-02-08
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
Qualifier:
according to
Guideline:
OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
semi-solid (amorphous): gel
Details on test material:
purity > 95%

In vitro test system

Test system:
human skin model
Source species:
human
Cell type:
non-transformed keratinocytes
Details on test system:
As the test item is highly viscous, Ukanol FR 70 was applied to a nylon mesh prior to application to the skin surface. 25 mg of test item were applied to the nylon mesh and incubated at 37°C, 5% CO2 and 95% relative humidity for 60 minutes to test for possible interaction between test substance and the mesh.
Control samples:
yes, concurrent no treatment
yes, concurrent positive control
Amount/concentration applied:
positive control: 30µl
negative control: 30µl
test item: 25 mg on a nylon mesh
Duration of treatment / exposure:
60 minutes
Duration of post-treatment incubation (if applicable):
42 hours
Number of replicates:
3

Results and discussion

In vitro

Resultsopen allclose all
Irritation / corrosion parameter:
% tissue viability
Run / experiment:
negative control
Value:
100
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid
Irritation / corrosion parameter:
% tissue viability
Run / experiment:
positive control
Value:
7.2
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid
Irritation / corrosion parameter:
% tissue viability
Run / experiment:
test item
Value:
98.3
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
Under the present test conditions, Ukanol FR 70 tested at an exposure time of 60 minutes and a 42-hour post-treatment incubation period, was non-cytotoxic and, hence, predicted to be non-irritant to skin in an experiment employing an artificial three-dimensional model of human skin. Hence, the test item did not show irritant properties and is therefore not classified as irritant (UN GHS no category).
Executive summary:

The purpose of this study was to determine cytotoxic properties of Ukanol FR 70 to skin cells, which might lead to irritation of human skin, by using an artificial three-dimensional model of human skin. The EpiDermTM model was employed.

Three tissues were used for each treatment and concurrent control groups. The optical density (OD) was determined by using the MTT (3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide, Thiazolyl blue) reduction assay and expressed as relative percentage of viability of the negative control-treated tissues.

As the test item is highly viscous, Ukanol FR 70 was applied to a nylon mesh prior to application to the skin surface. The nylon mesh loaded with 25 mg of test item was applied to the skin model which was moistened with Dulbecco’s phosphate buffered saline (D-PBS).D-PBS was used as the negative control.5% aqueous sodium dodecyl sulphate (SDS)was used as the positive reference item. An exposure time of 60 minutes was employed followed by a 42-hour post-treatment incubation period in fresh medium. The mean viability of cells exposed to Ukanol FR 70 was 98.3% of the negative controls and, hence, was well above the cut-off percentage cell viability value that distinguishes irritant from non-irritant test items of > 50%. Ukanol FR 70 was considered to be non-cytotoxic and predicted to be non-irritant to skin.

The mean optical density (OD) of 3 negative control tissues was 1.472 and was well within the acceptable range of ≥ 1.0 to ≤ 2.5.The viability of cells treated with the positive reference item, 5% SDS, was 7.2 of the negative control and fulfilled the acceptance criterion of ≤20%.

The standard deviation of all triplicates determined was below the limit of acceptance of 18%.Hence, all acceptance criteria were fulfilled.