3-bis(diisopropylamino)phosphanyloxypropanenitrile

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From Sept 12th 2019 to December 6th 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2010

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

Version / remarks:

2003

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:

3-({bis[bis(propan-2-yl)amino]phosphanyl}oxy)propanenitrile

EC Number:

600-337-9

Cas Number:

102691-36-1

Molecular formula:

C15H32N3OP

IUPAC Name:

3-({bis[bis(propan-2-yl)amino]phosphanyl}oxy)propanenitrile

Test material form:

liquid

Details on test material:

clear, colourless liquid

In vivo test system

Test animals

Species:

mouse

Strain:

CBA:J

Sex:

female

Details on test animals and environmental conditions:

Age at the Initiation of Dosing: Young adult animals (approximately 10 weeks old) were selected.
Weight at the Initiation of Dosing: 18.3 to 24.5 g.

Study design: in vivo (LLNA)

Vehicle:

acetone/olive oil (4:1 v/v)

Concentration:

Two test item concentrations were tested; a 50% and 100% concentration.

No. of animals per dose:

5 females

Details on study design:

Three groups of five animals were treated with one test item concentration per group. The highest test item concentration was selected from the pre-screen test. One group of five animals was treated with the vehicle.

Positive control substance(s):

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

Results and discussion

Positive control results:

The SI values calculated for Alpha- Hexylcinnamaldehyde, technical grade (CAS no. 101-86-0) at concentration of 5, 10 and 25% were 0.7, 2.2 and 6.4 respectively. An EC3 value of 12.8% was calculated using linear interpolation.

In vivo (LLNA)

Results

Results 1

Parameter:

EC3

Remarks:

as a percentage

Value:

52.6

Results 2

Key result

Parameter:

SI

Value:

1.2

Test group / Remarks:

25%

Results 3

Key result

Parameter:

SI

Value:

2.1

Test group / Remarks:

50%

Results 4

Key result

Parameter:

SI

Value:

19.4

Test group / Remarks:

100%

Applicant's summary and conclusion

Interpretation of results:

Category 1B (indication of skin sensitising potential) based on GHS criteria

Conclusions:

These results show that the test item elicits a SI ≥ 3. An EC3 value (the estimated test item concentration that will give a SI =3) of 52.6% was calculated.

The six-month reliability check with Alpha-hexylcinnamaldehyde indicates that the Local Lymph Node Assay as performed at the Test facility is an appropriate model for testing for contact hypersensitivity

Based on these results:
- According to the recommendations made in the test guidelines (including all amendments), the substance would be regarded as skin sensitizer.
- According to the Regulation (EC) No 1272/2008 on classification, labelling and packaging of items and mixtures (including all amendments), the substance should be classified as skin sensitizer (Category 1B) and labeled as H317: May cause an allergic skin reaction.

Executive summary:

The objective of this study was to evaluate whether the substance induces skin sensitization in mice after three epidermal exposures of the animals under the conditions described.

The six-month reliability check with Alpha-hexylcinnamaldehyde indicates that the Local Lymph Node Assay as performed at the test facility is an appropriate model for testing for contact hypersensitivity.

Test item concentrations selected for the main study were based on the results of a pre-screen test. Based on the results, the highest concentration required according to the guidelines was

selected. In the main study, three experimental groups of five female CBA/J mice were treated with test item concentrations of 25, 50 or 100% w/w on three consecutive days, by open

application on the ears. Five vehicle control animals were similarly treated, but with the vehicle alone (Acetone/Olive oil). Three days after the last exposure, all animals were injected with 3H-methyl thymidine and after five hours the draining (auricular) lymph nodes were excised and pooled for each animal. After precipitating the DNA of the lymph node cells, radioactivity measurements were performed. The activity was expressed as the number of disintegrations per minute (DPM) and a stimulation index (SI) was subsequently calculated

for each group.

The majority of auricular lymph nodes were considered normal in size, except for the nodes in the animals of 100% which were considered slightly enlarged in size. No macroscopic

abnormalities of the surrounding area were noted for any of the animals. Mean DPM/animal values for the experimental groups treated with test item concentrations 25, 50 and 100% were 888, 1565 and 14635 DPM, respectively. The mean DPM/animal value for the vehicle control group was 755 DPM. The SI values calculated for the test item concentrations 25, 50 and 100% were 1.2, 2.1 and 19.4, respectively. These results show that the test item elicits a SI ≥ 3. An EC3 value (the estimated test item concentration that will give a SI =3) of 52.6% was calculated.

Based on these results:

- According to the recommendations made in the test guidelines (including all amendments), the substance would be regarded as skin sensitizer.

- According to the Regulation (EC) No 1272/2008 on classification, labelling and packaging of items and mixtures (including all amendments), the substance should be classified as skin sensitizer (Category 1B) and labeled as H317: May cause an allergic skin reaction.