Benzenamine, N,N-dimethyl-, oxidized, molybdatetungstatephosphates

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20 November 2017 to 14 December 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

Benzenamine, N,N-dimethyl-, oxidized, molybdatetungstatephosphates

EC Number:

309-916-8

EC Name:

Benzenamine, N,N-dimethyl-, oxidized, molybdatetungstatephosphates

Cas Number:

101357-19-1

Molecular formula:

Reaction mass of C25 H30 N3. P Moy Wz O40 (y +z = 12) , C24 H28 N3. P Moy Wz O40 (y +z = 12) and C23 H26 N3. P Moy Wz O40 (y +z = 12)

IUPAC Name:

Reaction mass of [4-[bis[4-(dimethylamino)phenyl]methylene]cyclohexa-2,5-dien-1-ylidene]-dimethyl-ammonium. molybdatetungstatephosphates, [4-[[4-(dimethylamino)phenyl]-[4-(methylamino)phenyl]methylene]cyclohexa-2,5-dien-1-ylidene]-dimethyl-ammonium. molybdatetungstatephosphates and [4-[bis[4-(methylamino)phenyl]methylene]cyclohexa-2,5-dien-1-ylidene]-dimethyl-ammonium. molybdatetungstatephosphates

Test material form:

solid: nanoform, no surface treatment

Details on test material:

SOURCE OF TEST MATERIAL
-Product number: 0345N (skin sensitisation, OECD 422, eye irritation, acute oral toxicity)
0345F (Ames test)

- Purity Preparation containing ≥80% (treat as 100%)
- Physical form/colour: Violet powder
- Expiry date: Stable for at least 5 years from delivery date

-Shape Category: spheroidal
-Shape: spherycal
-pure shape: yes
-Typical composition: ca. 100%
-range >50 and < 100%

-D10, typical value: 30 nm, range: >1.5 and < 50nm
-D50, typical value: 45 nm, range: >15 and <100nm
-D90, typical value: 60nm, range: >25 and < 150nm

-Fraction in size range 1-100nm: > 50 and <100%

-Crystallinity:
Structure:
amorphous, pure structure

-SSA: BET surface area typically ca. 32-40 m2/g for product number 345F and 0345N)
Range > 10 and < 200 m2/g

-.no surface treatment

Storage conditions: Stored at ambient conditions in the dark (away from direct light)
- Safety precautions: Routine hygienic procedures (nitrile gloves, goggles, face mask)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Ferro Performance Pigments B.V., batch no 123442
- Expiration date of the lot/batch: 01 October 2022
- Purity test date: 2:80%


STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature in the dark
- Stability under test conditions: stable


FORM AS APPLIED IN THE TEST (if different from that of starting material) soution in dimethyl sulfoxide

In vivo test system

Test animals

Species:

mouse

Strain:

CBA/Ca

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source:
- Females (if applicable) nulliparous and non-pregnant: yes
- Microbiological status of animals, when known: not stated
- Age at study initiation: 8-12 weeks
- Weight at study initiation: 15 to 23 g
- Housing: The animals were housed in suspended solid floor polypropylene cages furnished with softwood wood:flakes.
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 5 days
- Indication of any skin lesions: not stated

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 25 °C
- Humidity (%): 30 to 70%
- Air changes (per hr): at least 15
- Photoperiod (hrs dark / hrs light): 12 hours continuous light and 12 hours darkness.
- IN-LIFE DATES: From: To: 20 November to 14 December 2017

Study design: in vivo (LLNA)

Vehicle:

dimethyl sulphoxide

Concentration:

25%, 10% or 5% w/w test item in DMSO

No. of animals per dose:

4

Details on study design:

PRE-SCREEN TESTS:
As no toxicological information was available regarding the systemic toxicity/irritancy potential of the test item, a preliminary screening test was performed using one mouse per test item concentration. The mouse was treated by daily application of 25 µL of the test item at concentrations of 50% and 25% w/w in dimethyl sulfoxide, to the dorsal surface of each ear for three consecutive days (Days 1, 2, 3). The mouse was observed twice daily on
Days 1, 2 and 3 and once daily on Days 4, 5 and 6. Local skin irritation was scored daily according to the scale included as Annex 5. Any clinical signs of toxicity, if present, were also recorded. The body weight of the mouse was recorded on Day 1 (prior to dosing) and on Day 6.
The thickness of each ear was measured using a Mitutoyo 547-300S gauge (Mitutoyo Corporation), pre-dose on Day 1, post dose on Day 3 and on Day 6. Any changes in the ear thickness were noted. Mean ear thickness changes were calculated between time periods Days 1 and 3 and Days 1 and 6. A mean ear thickness increase of equal to or greater than 25% was considered to indicate excessive irritation and limited biological relevance to the endpoint of sensitization


MAIN STUDY

ANIMAL ASSIGNMENT AND TREATMENT
Groups of four mice were treated with the test item at concentrations of 25%, 10% or 5% w/w in dimethyl sulfoxide.

TREATMENT PREPARATION AND ADMINISTRATION:

The mice were treated by daily application of 25 µL of the appropriate concentration of the test item to the dorsal surface of each ear for three consecutive days (Days 1, 2, 3). The test item formulation was administered using an automatic micropipette and spread over the dorsal surface of the ear using the tip of the pipette.

A further group of four mice received the vehicle alone in the same manner.


Five days following the first topical application of the test item or vehicle (Day 6) all mice were injected via the tail vein with 0.25 mL (250 µL) of phosphate buffered saline (PBS) containing3 H-methyl thymidine (3HTdR: 80 µCi/mL, specific activity 2.0 Ci/mmoL, ARC UK Ltd) giving a total of 20 µCi to each mouse.

Statistics:

The following computerized system was used in the study: Delta Controls - ORCAview

Results and discussion

In vivo (LLNA)

Results

Results 1

Key result

Parameter:

SI

Value:

3.38

Test group / Remarks:

Group1 5% test item w/w in DMSO

Remarks on result:

other: Skin sensitiser

Results 2

Key result

Parameter:

SI

Value:

5.63

Test group / Remarks:

Group 2 10% w/w test item in DMSO

Remarks on result:

other: Skin sensitiser

Results 3

Key result

Parameter:

SI

Value:

8.4

Test group / Remarks:

Group 3 25% w/w test item in DMSO

Remarks on result:

other: Skin senstiser

Applicant's summary and conclusion

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

The test item was considered to be a sensitizer under the conditions of the test.

Executive summary:

The test item was considered to be a sensitizer under the conditions of the test.