Hexane-1,3,6-tricarbonitrile

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2022.09.05-2022.09.26

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2022

Report date:

2022

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 442B (Skin sensitisation: Local Lymph Node Assay: BrdU-ELISA or –FCM)

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA): BrdU-ELISA

Test material

Test material information

Constituent 1

Reference substance name:

Hexane-1,3,6-tricarbonitrile

EC Number:

217-199-7

EC Name:

Hexane-1,3,6-tricarbonitrile

Cas Number:

1772-25-4

Molecular formula:

C9H11N3

IUPAC Name:

hexane-1,3,6-tricarbonitrile

In vivo test system

Test animals

Species:

mouse

Strain:

CBA:J

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source:KOATECH_Korea
- Females (if applicable) nulliparous and non-pregnant: yes
- Microbiological status of animals, when known: NONE
- Age at study initiation: 9 weeks
- Weight at study initiation: 21.2-25.6g
- Housing:Rodents room
- Diet (e.g. ad libitum):libitum
- Water (e.g. ad libitum):libitum
- Acclimation period:The animals of receipt were quarantined for more than 3 days in quarantine room, and acclimated to the laboratory conditions for more than 5 days. All animals were observed once a day for general symptoms and only healthy animals were used in this study.


ENVIRONMENTAL CONDITIONS
- Temperature (°C):21.2 ~ 23.7 ºC
- Humidity (%):49.6 ~ 57.4 %
- Air changes (per hr):10 - 15 air exchanges / hour
- Photoperiod (hrs dark / hrs light):12 hours (8 AM light on ~ 8 PM light off )

Study design: in vivo (LLNA)

Vehicle:

dimethylformamide

Remarks:

SIGMA-ALDRICH, STBK2956

Concentration:

The preliminary test and the main test were prepared at a concentration of 100%, 50% (v/v) and 25% (v/v).

No. of animals per dose:

4

Positive control substance(s):

eugenol (CAS No 97-53-0)

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Value:

2.439

Test group / Remarks:

positive control group

Results 2

Parameter:

SI

Value:

1.314

Test group / Remarks:

Test substance (100 %(v/v))

Results 3

Parameter:

SI

Value:

1.174

Test group / Remarks:

Test substance (50 %(v/v))

Results 4

Parameter:

SI

Value:

1.128

Test group / Remarks:

Test substance (25 %(v/v))

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The stimulation index (SI) in animals treated with vehicle control group, 100 %, 50 % and 25 %(v/v) concentrations of test substance and positive control group were calculated as 1.000, 1.314, 1.174, 1.128 and 2.439, respectively. The SI obtained with 1,3,6-Hexanetricarbonitrile concentrations up to 100 % in the present study were below 1.6 and, therefore, support non-sensitizing properties of 1,3,6-Hexanetricarbonitrile when tested in a positive control group.

Executive summary:

This study was performed to evaluate skin sensitization of 1,3,6-Hexanetricarbonitrile in female CBA/J mouse. All animals were observed once daily for clinical signs and mortality throughout the study period. Body weights were recorded on Day 1 and Day 6. On Day 5, 25 μL of test solution was applied to the dorsum of both ears of a mouse daily for 3 consecutive days. 0.5 mL of BrdU solution was administered intra-peritoneally. Approximately 24 hours (Day 6) after BrdU solution injection, euthanasia was performed with CO2 gas. After that, excised the draining auricular lymph nodes from each mouse ear, and the lymph nodes were subjected to cell proliferation and absorbance was measured at the ELISA reader.
The results were as follows.
1) No death of animal was observed during the study period.
2) No clinical signs related to the test substance administration were observed.
3) No abnormal body weight changes were observed in preliminary or main tests.
4) No abnormal ear thickness changes were observed in preliminary or main tests.
5) No abnormal local skin irritation changes were observed in preliminary or main tests.
6) The stimulation index in animals treated with vehicle control group, 100 %, 50 % and 25 %(v/v) concentrations of test substance and positive control group were calculated as 1.000, 1.314, 1.174, 1.128 and 2.439, respectively. The SI obtained with 1,3,6-Hexanetricarbonitrile concentrations up to 100 % in the present study were below 1.6 and, therefore, support non-sensitizing properties of 1,3,6-Hexanetricarbonitrile when tested in a positive control group.
As a result, the test substance(1,3,6-Hexanetricarbonitrile) was not a dermal sensitizer in the Local Lymph Node Assay.
The concentrations according to purity of test substances 1,3,6-Hexanetricarbonitrile 100 %, 50 % (v/v) and 25 % (v/v) were 99.67 %, 49.835 %, and 24.9175 %.