Formamide, N-[(2-bromo-5-hydroxy-4-methoxyphenyl)methyl]-N-[2-(4-hydroxyphenyl)ethyl]-

Endpoint summary

Description of key information

Skin sensitisation:

In a K2 local lymph node assay in the mouse according to SPL Standard Test Method 595.13, the substance is observed to be not sensitising to the skin (Sanders, 2005).

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Reference 1

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2005-10-24 to 2005-11-15

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

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

Deviations:

yes

Remarks:

limited information on test item, test animals and test conditions

Qualifier:

according to guideline

Guideline:

other: SPL Standard Test Method 595.13.

GLP compliance:

no

Remarks:

The study was conducted in a facility operating to Good Laboratory Practice within the UK national GLP monitoring programme, but the study report has not been audited by the QA unit. No formal claim of GLP compliance is made for this study.

Type of study:

mouse local lymph node assay (LLNA)

Specific details on test material used for the study:

no data

Species:

mouse

Strain:

CBA/Ca

Sex:

not specified

Details on test animals and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 18-23 grams

ENVIRONMENTAL CONDITIONS: no data

Vehicle:

dimethyl sulphoxide

Concentration:

as a solution in dimethyl sulphoxide at concentrations of 50%, 25% and 10% w/w
A further group of four animals was treated with dimethyl sulphoxide alone.

No. of animals per dose:

four/dose group

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: no data
- Irritation: no data
- Lymph node proliferation response: no data
- Systemic toxicity: Following a preliminary sighting test, no signs of systemic toxicity were observed at a concentration of 50% w/w in dimethyl sulphoxide.
- Ear thickness measurements: no data
- Erythema scores: no data

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: Local Lymph Node Assay
- Criteria used to consider a positive response: Test-to-control ratio greater than 3.0 indicates a positive result.

TREATMENT PREPARATION AND ADMINISTRATION:
- 50 uL (25 uL per ear) of the test substance as a solution in dimethyl sulphoxide at concentrations of 50%, 25% and 10% w/w was applied to the dorsal surface of the ear.
- A further group of four animals was treated with dimethyl sulphoxide alone.

Positive control substance(s):

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

other: 2,4 Dinitrobenzene sulphonic acid, sodium salt (DNBS): 1%, 10%, 20% v/v in 1% pluronic L92 in distilled water

Statistics:

no data

Positive control results:

see 'Any other information on results incl. tables'

Parameter:

SI

Value:

1.31

Test group / Remarks:

10% (w/w) in dimethyl sulphoxide

Parameter:

SI

Value:

1.1

Test group / Remarks:

25% (w/w) in dimethyl sulphoxide

Parameter:

SI

Value:

1.15

Test group / Remarks:

50% (w/w) in dimethyl sulphoxide

Cellular proliferation data / Observations:

CELLULAR PROLIFERATION DATA
DPM/node obtained by dividing the DPM value by 8 (total number of lymph nodes)
vehicle: 1248.42
10% (w/w) group: 1440.78
25% (w/w) group: 1377.83
50% (w/w) group: 1632.01

DETAILS ON STIMULATION INDEX CALCULATION
The Stimulation Index (SI) was expressed as the mean radioactive incorporation for each treatment group divided by the mean radioactive incorporation of the vehicle control group

EC3 CALCULATION
Not applicable (SI < 3.0)

CLINICAL OBSERVATIONS:
no signs of systemic toxicity

BODY WEIGHTS
The mean body weight gain shown by the animals over the study period was considered to be normal.

Positive Control Local Lymph Node Assay in the Mouse (2005)

Start Date	Finish Date	Test Material	Concentration	Vehicle	Stimulation Index^a	Classification^b
04/03/2005	10/03/2005	α‑Hexylcinnamaldehyde, tech., 85%	5%, 10%, 25% v/v	acetone/olive oil 4:1	2.76, 3.34, 8.91	Positive
20/04/2005	26/04/2005	α‑Hexylcinnamaldehyde, tech., 85%	5%, 10%, 25% v/v	ethanol/distilled water 7:3	2.64, 8.36, 12.94	Positive
14/07/2005	20/07/2005	α‑Hexylcinnamaldehyde, tech., 85%	5%, 10%, 25% v/v	1% pluronic L92 in distilled water	0.86, 1.50, 6.17	Positive
14/07/2005	20/07/2005	2,4 Dinitrobenzene sulphonic acid, sodium salt (DNBS)	1%, 10%, 20% v/v	1% pluronic L92 in distilled water	1.16, 9.59, 20.71	Positive

 

a=        Ratio of test to control lymphocyte proliferation

b=        Stimulation index greater than 3.0 indicates a positive result

* =        Standard Test Method 595 (Pooled nodes)

·=        Standard Test Method 599 (Individual nodes)

Interpretation of results:

GHS criteria not met

Conclusions:

The test item was considered to be a non-sensitiser to the skin under the conditions of the test.

Reference 2

Endpoint:

skin sensitisation: in vitro

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

In order to assess the cutaneous allergenic potential of the substance, a local lymph node assay in the mouse was performed. Following a preliminary sighting test, at which there were no signs of systemic toxicity at a concentration of 50% w/w in dimethyl sulphoxide, three groups, each of four animals, were treated with 50 µl (25 µl per ear) of the test material as a solution in dimethyl sulphoxide at concentrations of 50%, 25% and 10% w/w. Clinical signs and mortality were observed during 6 days after administration of the substance with observations pre-dosing and 1 hour postdosing on days 1, 2 and 3. Individual body weights were measured on days 1 and 6 and body weight changes were calculated.
The stimulation index, calculated based on the mean radioactive incorporation for each treatment group divided by the mean radioactive incorporation of the vehicle control groups, was lower than 3 at each test concentration which means no positive results have been observed. Therefore, T002078 was considered to be a non-sensitiser to the skin under the conditions of the test. In addition, no signs of systemic toxicity have been observed.

 

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Skin sensitisation:

Based on the study results and the criteria of the CLP Regulation, the test item is not regarded as a potential skin sensitiser.

Respiratory sensitisation:

No data were available to decide on the classification for respiratory sensitisation.