Methanesulfonamide, N-[2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]-6-fluorophenyl]-1,1-difluoro-N-methyl-

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

09 July -04 Aug 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

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:

EPA OPPTS 870.2600 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

N-[2-(4,6-dimethoxy-1,3,5-triazine-2-carbonyl)-6-fluorophenyl]-1,1-difluoro-N-methylmethanesulfonamide

EC Number:

620-056-5

Cas Number:

874195-61-6

Molecular formula:

C14H13F3N4O5S

IUPAC Name:

N-[2-(4,6-dimethoxy-1,3,5-triazine-2-carbonyl)-6-fluorophenyl]-1,1-difluoro-N-methylmethanesulfonamide

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/J

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: R. Janvier, Le Genest St Isle, France
- Age at study initiation: at least 8 weeks old
- Weight at study initiation: 20.6-23.9 g
- Housing: Mice were housed individually in suspended, stainless steel, wire-mesh cages.
- Diet: certified rodent pellet diet and irradiated: A04C-10, S.A.F.E. (Scientific Animal Food and Engineering, Route de Saint Bris, Augy, France); ad libitum
- Water: tap water; ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 40-70
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 2010-07-21 To: 2010-08-02

Study design: in vivo (LLNA)

Vehicle:

dimethylformamide

Concentration:

25, 50 and 100% (w/v)

No. of animals per dose:

5

Details on study design:

RANGE FINDING TESTS:
- Irritation: Concentrations of test substance in dimethylformamide were chosen based on results of a screening test, in which no irritation (measured by ear weight) was observed at concentrations of 100%. Mean ear weight value of 12.6 mg was measured in the group treated at a concentration of 100%. This represented a variation of 5.9% in relation to the value obtained in control animals (11.9 mg). The values in treated and control groups were considered similar and the formulation was not considered to be irritant at 100%.

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: 3H-methyl thymidine incorporation determined by beta-scintillation
- Criteria used to consider a positive response: A test substance is regarded as a skin sensitizer if one concentration of the test substance results in a stimulation index of three or greater, when compared to control values in the absence of skin irritation and if there is a dose-related response.

TREATMENT PREPARATION AND ADMINISTRATION:
25 µL of test substance was applied to the dorsal surface of each ear of each mouse. The application was repeated on Days 2 and 3; local irritation reactions were assessed. On Day 6 an injection of 250 µL saline (0.9% NaCl) containing 20 µCi of 3H-methyl thymidine (3H-TdR) was made into the tail vein of each experimental mouse. Five hours later (± 30 min), the draining auricular lymph nodes from each mouse were placed in an individual tube containing physiological saline and were disaggregated by crushing with a plastic piston. A cell suspension was obtained, free of connective tissue. Cell suspensions were washed with 4 mL of 0.9% physiological saline, centrifuged for 20 min at 1800 rpm and the pellets obtained were resuspended in 2 mL of 5% trichloroacetic acid and stored overnight at 5±3°C. After a final centrifugation, the pellets were resuspended in 1 mL of saline, mixed and then placed for approximately 25 min in an Ultrasonic Bath to ensure a thoroughly dispersed suspension. Once prepared cell suspensions were added to numbered scintillation pots containing 19 mL of scintillation fluid and assayed in a beta-counter.

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Results and discussion

Positive control results:

The stimulation index (SI) value of the positive control alpha-hexylcinnamaldehyde was 4.5 (±1.1) at a treatment concentration of 30%, thus meeting the reliability criteria for the LLNA (SI >3: positive response).

In vivo (LLNA)

Results

Results 1

Key result

Parameter:

SI

Remarks:

25%

Value:

0.6

Variability:

SD +/- 0.2

Test group / Remarks:

n = 5

Results 2

Key result

Parameter:

SI

Remarks:

50%

Value:

0.5

Variability:

SD +/- 0.2

Test group / Remarks:

n = 5

Results 3

Key result

Parameter:

SI

Remarks:

100%

Value:

0.7

Variability:

SD +/- 0.4

Test group / Remarks:

n = 5

Any other information on results incl. tables

Mortality was observed on two animals treated with the positive control. Before death these animals had soiled fur. No mortality or clinical signs were observed on the surviving animals of the positive control group, on the control animals or on animals treated with the test substance. No cutaneous reactions were observed in the vehicle, positive control or treated groups.

The disintegrations per minute (DPM) values of the test substance were 845 (± 430.7), 766 (± 297.3) and 987 (± 627.3) at treatment concentrations of 25, 50 and 100%, respectively. The DPM value of the control group was 1489 (± 430.7).

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

CLP: not classified
DSD: not classified