Triethylammonium bromide

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

November 2013 - January 2014

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

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:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

Principles of method if other than guideline:

Not reported.

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:

Triethylammonium bromide

EC Number:

211-263-8

EC Name:

Triethylammonium bromide

Cas Number:

636-70-4

Molecular formula:

C6H15N.BrH

IUPAC Name:

N,N-diethylethanaminium bromide

Test material form:

solid: crystalline

Details on test material:

Identification: triethylammonium bromide
Batch: 32541
Purity: 98.2 % (argentometry)
Expiry Date: September 10, 2028
Storage Conditions: At room temperature, light protected

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/CaOlaHsd

Sex:

female

Details on test animals and environmental conditions:

Test System
Test system: Mice, CBA/CaOlaHsd
Rationale: Recognised as the recommended test system.
Source: Harlan Laboratories B.V., Postbus 6174, 5960 AD Horst / The Netherlands
Number of animals for the pre-test: 2 females
Number of animals for the main study: 16 females
Number of animals per group: 4 females (nulliparous and non-pregnant)
Number of test groups: 3
Number of control (vehicle) groups: 1
Age: Pre-test: 8 - 9 weeks (beginning of treatment)
Main study: 9 - 10 weeks (beginning of treatment)
Identification: The animals were distributed into the test groups at random. All animals belonging to the same experimental group were kept in one cage. In the main experiment, the animals were identified by tail tags. In the pre-experiment, animals were identified by cage
number.
Acclimation: At least 5 days prior to the start of dosing under test conditions after health examination. Only animals without any visible signs of illness were used for the study.

Husbandry
The animals were kept conventionally. The experiment was conducted under standard laboratory conditions.
Housing: group
Cage Type: Makrolon Type II (pre-test) / III (main study), with wire mesh top
Bedding: granulated soft wood bedding
Feed: 2018C Teklad Global 18% protein rodent diet (certified), ad libitum
Water: tap water, ad libitum
Environment:
temperature: 22 + 2°C
relative humidity: approx. 27-65%
artificial light: 6.00 a.m. - 6.00 p.m.

Study design: in vivo (LLNA)

Vehicle:

other: ethanol/water (7+3, v/v)

Concentration:

10, 25 and 50% (w/w) in ethanol/water (7+3, v/v)

No. of animals per dose:

4

Details on study design:

Each test group of mice was treated by (epidermal) topical application to the dorsal surface of each ear with test item concentrations of 10, 25 and 50% (w/w) in ethanol/water (7+3, v/v). The application volume, 25 μL/ear/day, was spread over the entire dorsal surface (∅ ∼ 8 mm) of each ear once daily for three consecutive days. A further group of mice (control animals) was treated with an equivalent volume of the relevant vehicle alone (control animals).

Positive control substance(s):

other: α- hexyl cinnamaldehyde dissolved in acetone/olive oil (4+1, v/v)

Statistics:

Statistical Analysis
The mean values and standard deviations were calculated in the body weight tables.
However, both biological and statistical significance were considered together.

Results and discussion

Positive control results:

Experiment performed in October 2013 (Harlan study number 1585700).
Positive control substance: α-Hexylcinnamaldehyde
Vehicle: acetone/olive oil (4+1, v/v)

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: Test item concentration / S.I. 0 / 1.0 10 / 1.1 25 / 0.89 50 / 0.85

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: Test item concentration / Measurement DPM / DPM per lymph node 0 / 3665.0 / 455.7 10 / 4032.0 / 501.6 25 / 3267.0 / 407.1 50 / 3110.0 / 386.3

Any other information on results incl. tables

Viability / Mortality

No deaths occurred during the study period.

Clinical Signs

No symptoms of local skin irritation at the ears of the animals and no signs of systemic toxicity

were observed during the study period.

Body Weights

The body weight of the animals, recorded prior to the first application and prior to treatment with

3HTdR, was within the range commonly recorded for animals of this strain and age.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: expert judgment

Conclusions:

The test item triethylammonium bromide was not a skin sensitiser under the test conditions of this study.

Executive summary:

In the study the test item triethylammonium bromide formulated in ethanol/water (7+3, v/v) was assessed for its possible skin sensitising potential. For this purpose a local lymph node assay was performed using test item concentrations of 10, 25

and 50% (w/w). The animals did not show any signs of systemic toxicity or local skin irritation during the course of the study and no cases of mortality were observed. In this study Stimulation Indices (S.I.) of 1.10, 0.89 and 0.85 were determined with the test item

at concentrations of 10, 25 and 50% (w/w) in ethanol/water (7+3, v/v), respectively.

The relative humidity in the animal room was between approximately 27 - 65% instead of 45 - 65% for few hours. This deviation to the study plan, however, does not affect the validity of the study.

The test item triethylammonium bromide was not a skin sensitiser under the test conditions of

this study.