Registration Dossier

Administrative data

Endpoint:
skin irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
November 22-25, 2016
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2016
Report Date:
2016

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 431 (In Vitro Skin Corrosion: Human Skin Model Test)
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: flakes
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Mitsubishi-Kagaku Foods Corporation, 6912911B
- Expiration date of the lot/batch: March 27, 2018

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: < 15 degrees C, protected from light
- Stability under test conditions: slightly hydroscopic

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Final preparation of a solid: The test substance was crushed into a powder using a mortar and pestle.

FORM AS APPLIED IN THE TEST (if different from that of starting material): powder

In vitro test system

Test system:
human skin model
Source species:
human
Cell type:
non-transformed keratinocytes
Justification for test system used:
The reconstructed human epidermis model closely mimics the biochemical and physiological properties of the human epidermis.
Vehicle:
other:
Remarks:
Dulbecco's phosphate buffered saline
Details on test system:
SKIN DISC PREPARATION
- Procedure used: Tissues were transferred to 6 well plates with 0.9 mL assay medium per well. The surface was dried, and incubated for 1 hr at 37 degrees C in 5% CO2. The tissues were transferred to new wells with 0.9 mL assay medium, and incubated for 18 hrs at 37 degrees C in 5% CO2.
- Quality control for skin discs: Visual inspection
TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37 degrees C
- Temperature of post-treatment incubation (if applicable): 37 degrees C
REMOVAL OF TEST MATERIAL AND CONTROLS
- Number of washing steps: 19
DYE BINDING METHOD
- Dye used in the dye-binding assay: MTT
- Wavelength: 570 nm
- Filter bandwidth: 30 nm

Control samples:
yes, concurrent negative control
yes, concurrent positive control
Amount/concentration applied:
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 25 mg
- Concentration (if solution): 25 mg in 25 uL DPBS

VEHICLE
- Amount(s) applied (volume or weight with unit): 25 uL

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 30 uL DPBS


POSITIVE CONTROL
- Amount(s) applied (volume or weight): 30 uL
- Concentration (if solution): 5%
Duration of treatment / exposure:
42 hrs
Duration of post-treatment incubation (if applicable):
3 hrs
Number of replicates:
3

Results and discussion

In vitro

Results
Irritation / corrosion parameter:
% tissue viability
Value:
101.3
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid
Other effects / acceptance of results:
- OTHER EFFECTS:
- Visible damage on test system: no
- Direct-MTT reduction: no
- Colour interference with MTT: no


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:
LMDT is not irritating to skin.
Executive summary:

The skin irritation potential of LMDT was tested in an OECD Guideline 431 study using a human skin model. The test substance was placed on the human skin model for 1 hr, and then incubated for 42 hrs. LMDT did not show any evidence of skin irritation potential. LMDT is not classified as irritating to skin.