Reaction mass of N-butylphosphorothioic triamide and N-propylphosphorothioic triamide

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: According to GLP; OECD-guideline 429; 2004/73/EC, B.42.; US EPA OPPTS 870.2600.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of N-butylphosphorothioic triamide and N-propylphosphorothioic triamide

EC Number:

700-457-2

Molecular formula:

Unspecified

IUPAC Name:

Reaction mass of N-butylphosphorothioic triamide and N-propylphosphorothioic triamide

Details on test material:

- Name of test material (as cited in study report): LIMUS-Sambaydestillation
- Test-substance No.: 07/0684-1
- Physical state: solid/yellowish
- Analytical purity: 87%
- Lot/batch No.: 8712 / 062
- Storage condition of test material: < -18°C
- Stability: stable over 5 days

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/J

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Research Models and Services, Germany GmbH, Sandhofer Weg 7, 97633 Sulzfeld
- Age at study initiation: 6 - 12 weeks
- Weight at study initiation: 18.9 - 21.4 g
- Housing: Makrolon cage, type II
- Diet (e.g. ad libitum): Kliba-Labordiät (Maus / Ratte Haltung “GLP”), Provimi Kliba SA, Kaiseraugst, Basel, Switzerland, ad libitum
- Water (e.g. ad libitum): tap water
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

methyl ethyl ketone

Concentration:

0, 3, 10 and 50% of the test substance in MEK (methyl ethyl ketone)

No. of animals per dose:

5

Details on study design:

RANGE FINDING TESTS:
- Irritation: the results of a pretest with a 50% test-substance preparation in MEK (methyl ethyl ketone) were considered, which showed some increase in lymph node weights without definitive increased ear weights which is still interpreted as indication of ear skin irritation. Higher concentrations we re not tested in order to avoid ear skin irritation and because the 50% concentration is a suspension and well above the effect level of mild to moder ate skin sensitizers, leading to a sufficiently stringent conduct of the study.


MAIN STUDY

TREATMENT PREPARATION AND ADMINISTRATION:
Groups of 5 female CBA/J mice each were treated with 3%, 10% and 50% w/w preparations of the test substance in MEK (methyl ethyl ketone) or with the vehicle alone. The study used 3 test groups and 1 control group. Each test animal was applied with 25 μL per ear of the respective test-substance preparation to the dorsum of both ears for three consecutive days. The control group was treated with 25 μL per ear of the vehicle alone. Three days after the last application the mice were injected intravenously with 20 μCi of 3H-thymidine in 250 μL of sterile saline into a tail vein. About 5 hours after the 3H-thymidine injection, the mice were sacrificed and the auricular lymph nodes were removed. The weights of each animal’s pooled lymph nodes were determined. Thereafter lymph nodes were pooled group wise and further evaluated by measuring their cellular content and 3H-thymidine incorporation into the lymph node cells (indicators of cell proliferation). Moreover, a defined area with a diameter of 0.8 cm was punched out of the apical part of each ear and for each test group the weight of the pooled punches was determined in order to obtain an indication of possible skin irritation.

Positive control substance(s):

other: A concurrent positive control (reliability check) with a known sensitizer was not included into this study. Studies using the positive control substance Alpha-Hexylcinnamaldehyde are performed twice a year in the laboratory in order to show that the test.

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: see discussion

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: see table in any other information on results incl tables

Any other information on results incl. tables

Test group	Treatment	Cell Count Stimulation Index	3H-thymidine incorporation Stimulationindex	Lymph Node Weight StimulationIndex	Ear Weight Stimulation Index
1	vehicle MEK	1.00	1.00	1.00	1.00
2	3% in MEK	1.20	1.64	1.07	1.01
3	10% in MEK	1.23	2.54	1.26	1.02
4	50% in MEK	1.90	9.11	1.75	1.08

The threshold concentraton for sensitization iduction was >10% <50%. The estimated concentraton that leads to the SI of 1.5 for cell count (ECC 1.5) and the estimated concentration that leads to the SI of 3.0 for 3H-thymidine incorporation (EC 3) were calculated by linear regression from the results of the 10% and 50% concentrations to be 26.1% and 12.8%, respectively.

Applicant's summary and conclusion

Interpretation of results:

sensitising

Remarks:

Migrated information

Conclusions:

Thus it is concluded that LIMUS-Sambaydestillation shows a skin sensitizing effect in the Murine Local Lymph Node Assay under the test conditions chosen. According to the findings of this study, the test substance has to be classified R43 (Directive 67/548/EEC) and Skin sensitisation Cat. 1 (GHS (UN)).