Fatty acids, tall-oil, reaction products with 2-[(2-aminoethyl)amino]ethanol

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-07-16 to 2012-11-05

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study has been performed according to OECD guideline 429 and EU method B.42 in a GLP-certified testing facility

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

(During the second and the fourth pre-test and during the acclimation phase of the main test, the relative humidity in the animal room was >95 % instead of 45 - 65 % for several hours due to cleaning and disinfection work in the animal house.)

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

(During the second and the fourth pre-test and during the acclimation phase of the main test, the relative humidity in the animal room was >95 % instead of 45 - 65 % for several hours due to cleaning and disinfection work in the animal house.)

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

Strain:

other: CBA/CaOlaHsd

Sex:

female

Vehicle:

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

Concentration:

0.05 %
0.1 %
0.25 %

No. of animals per dose:

4

Details on study design:

PRE-SCREEN TESTS:
- Compound solubility: soluble in acetone/olive oil
- Irritation: yes, at concentrations > 1%
- Systemic toxicity:
- Ear thickness measurements: yes
- Erythema scores: yes

MAIN STUDY

ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method:
- Criteria used to consider a positive response:

TREATMENT PREPARATION AND ADMINISTRATION:

Positive control substance(s):

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

Key result

Parameter:

SI

Value:

1

Test group / Remarks:

control

Key result

Parameter:

SI

Value:

1.37

Test group / Remarks:

0.05%

Key result

Parameter:

SI

Value:

1.53

Test group / Remarks:

0.1%

Key result

Parameter:

SI

Value:

2

Test group / Remarks:

0.25%

Viability / mortality

No deaths occurred during the study period.

Clinical signs

No systemic findings were observed during the study period. On days 3 and 4, the animals treated with a test item concentration of 0.1% showed an erythema of the ear skin (score: 1). On days 3-6, the animals treated with the high dose showed an erythema of the ear skin as well (score: 1 on days 5 and 6, score: 2 on days 3 and 4).

 

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.

Interpretation of results:

other: not sensitising according to EU regulation

Conclusions:

The test item 400112 was not a skin sensitiser under the test conditions of this study.

Executive summary:

In order to study a possible skin sensitising potential of 400112, three groups each of four female mice were treated once daily with the test item at concentrations of 0.05, 0.1 and 0.25% (w/w) in acetone:olive oil (4:1; v/v) by topical application to the dorsum of each ear for three consecutive days. The highest concentration tested was the highest concentration that could be achieved whilst avoiding systemic toxicity and excessive local skin irritation as confirmed by four pre-experiments. A control group of four mice was treated with the vehicle (acetone:olive oil (4:1; v/v)) only. Five days after the first topical application the mice were injected intravenously into a tail vein with radio-labelled thymidine (³H-methyl thymidine). Approximately 5 h after intravenous injection, the mice were sacrificed, the draining auricular lymph nodes excised and pooled per group. Single cell suspensions of lymph node cells were prepared from pooled lymph nodes, which were subsequently washed and incubated with trichloroacetic acid overnight. The proliferative capacity of pooled lymph node cells was determined by the incorporation of ³H-methyl thymidine measured in a β-scintillation counter.

All treated animals survived the scheduled study period and no signs of systemic toxicity were observed. On days 3 and 4, the animals treated with a test item concentration of 0.1% showed an erythema of the ear skin (score: 1). On days 3-6, the animals treated with the high dose showed an erythema of the ear skin as well (score: 1 on days 5 and 6, score: 2 on days 3 and 4).

A test item is regarded as a sensitiser in the LLNA if the exposure to one or more test concentration resulted in a 3-fold or greater increase in incorporation of ³HTdR compared with concurrent controls, as indicated by the Stimulation Index (S.I.). The estimated concentration of test item required to produce a S.I. of 3 is referred to as the EC3 value. In this study Stimulation Indices of 1.37, 1.53 and 2.0 were determined with the test item at concentrations of 0.05, 0.1 and 0.25% (w/w) in acetone:olive oil (4 :1; v/v). A clear dose response was observed.

The EC3 value could not be calculated, since none of the tested concentrations induced a S.I. greater than the threshold value of 3.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

According to the results of the LLNA test, 400112 does not meet the current EU-CLP criteria for classification as a skin sensitiser up to a concentration of 0.25 % (w/w). Higher concentrations could not be tested due to strong irritation of the animals' ears.