2-propanol and 2-butanol production, distn. residues

Endpoint summary

Description of key information

The test item „2-propanol and 2-butanol production, distn. residue“, dissolved in acetone:olive oil (4+1), was assessed for its possible contact allergenic potential in an OECD 429 (EU B.42) study under GLP.

For this purpose, a local lymph node assay was performed using test item concentrations of 25, 50, and 100%.

The animals did not show any clinical signs during the course of the study and no cases of mortality were observed.

In this study Stimulation Indices (S.I.) of 0.84, 1.14, and 1.34 were determined with the test item at concentrations of 25, 50, and 100% in acetone:olive oil (4+1), respectively, and as a result the test item „2-propanol and 2-butanol production, distn. residue“ is not considered sensitising to skin.

The respiratory sensitisation potential of „2-propanol and 2-butanol production, distn. residue“ was not tested.

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:

June 8, 2010 - June 30, 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study under GLP with full documentation

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

The relative humidity in the animal room was between approximately 39 - 81 % for few hours. This deviation to the study plan, however, does not affect the validity of the study.

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

The relative humidity in the animal room was between approximately 39 - 81 % for few hours. This deviation to the study plan, however, does not affect the validity of the study.

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

Strain:

other: CBA/CaOlaHsd

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories B.V., Postbus 6174, 5960 AD Horst / The Netherlands
- Age at study initiation: 8 - 12 weeks (beginning of treatment)
- Weight at study initiation: 18.4 - 23.6 g at the start of the main experiment
- Housing: Single caging. The animals were distributed into the test groups at random and identified by cage number.
- Diet (e.g. ad libitum): pelleted standard diet, ad libitum (Harlan Laboratories B.V., 5960 AD Horst / Netherlands)
- Water (e.g. ad libitum): tap water, ad libitum, (Gemeindewerke, 64380 Rossdorf, Germany)
- Acclimation period: 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.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ±2 °C
- Humidity (%): 39 - 81%
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): artificial light 6.00 a.m. - 6.00 p.m.

Vehicle:

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

Concentration:

25, 50 or 100%

No. of animals per dose:

4 females per group

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: The highest test item concentration, which can be technically used was 100% of the undiluted test item.
- Irritation: To determine the highest non-irritant test concentration, a pre-test was performed in two animals. Two mice were treated with concentrations of 50 and 100% each on three consecutive days. In the pre-test clinical signs were recorded within 1 hour and 24 ±4 hours after each application as well as on day 7. At the tested concentrations the animals did not show any signs of irritation or systemic toxicity.
- Lymph node proliferation response: Not reported

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: LLNA
- Criteria used to consider a positive response: A test item is regarded as a sensitiser in the LLNA if the following criteria are fulfilled: (1) that exposure to at least one concentration of the test item resulted in an incorporation of 3HTdR at least 3-fold or greater than that recorded in control mice, as indicated by the stimulation index. (2) that the data are compatible with a conventional dose response, although allowance must be made (especially at high topical concentrations) for either local toxicity or immunological suppression.


TREATMENT PREPARATION AND ADMINISTRATION:
Acclimatisation: 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.
Each test group of mice was treated by topical (epidermal) application to the dorsal surface of each ear (left and right) with different test item concentrations of 25, 50, and 100% (w/w) in acetone:olive oil (4:1). The application volume, 25 µl, was spread over the entire dorsal surface (diameter approximately 8 mm) of each ear once daily for three consecutive days. A further group of mice was treated with an equivalent volume of the relevant vehicle alone (control animals).
Application was without occluded patch.

Endpoint to measure effect:
Five days after the first topical application, the mice were intravenously injected into a tail vein with radio-labelled thymidine (3H-methyl thymidine). Approximately five hours after intraveinous injection, the mice were sacrificed and 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 proliferate capacity of pooled lymph node cells was determined by the incorporation of 3H-methyl thymidine measured in a beta-scintillation counter.

Positive control substance(s):

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

Statistics:

The mean values and standard deviations were calculated in the body weight tables

Positive control results:

Control group: 4549 DPM
5% group: 9263 DPM
10% group: 15495 DPM
25% group: 27949 DPM

Stimulation indexes were 2.04, 3.41 and 6.14 for the 5%, 10% and 25% groups respectively

Parameter:

SI

Value:

0.84

Test group / Remarks:

25% group

Parameter:

SI

Value:

1.14

Test group / Remarks:

50% group

Parameter:

SI

Value:

1.34

Test group / Remarks:

100% group

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: Control group: 3494; 25% group: 2928; 50% group: 3971; 100% group: 4677

No deaths occurred during the study period.

No symptoms of local toxicity at the ears of the animals and no systemic findings were observed during the study period.

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:

GHS criteria not met

Conclusions:

The sensitisation properties of „2-propanol and 2-butanol production, distn. residue“ were tested with the LLNA method. No sensitisation effect were observed. Consequently, the test item is not sensitising.

Executive summary:

In the study the test item „2-propanol and 2-butanol production, distn. residue“, dissolved in acetone:olive oil (4+1), was assessed for its possible contact allergenic potential in this study under GLP. The guidelines OECD 429 and EU B.42 were followed.

For this purpose a local lymph node assay was performed using test item concentrations of 25, 50, and 100%.

The animals did not show any clinical signs during the course of the study and no cases of mortality were observed.

In this study Stimulation Indices (S.I.) of 0.84, 1.14, and 1.34 were determined with the test item at concentrations of 25, 50, and 100% in acetone:olive oil (4+1), respectively.

The test item „2-propanol and 2-butanol production, distn. residue“ was not a skin sensitiser.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

The skin sensitisation properties of „2-propanol and 2-butanol production, distn. residue“ were tested with the mouse local lymph node assay (LLNA) method. This study was conducted following the OECD 429 and EU B.42 methods. No sensitisation effects were observed, and consequently the test item is not classified as skin sensitising.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information:

The respiratory sensitisation of „2-propanol and 2-butanol production, distn. residue“ was not tested.

Justification for classification or non-classification

The criteria for the classification of „2-propanol and 2-butanol production, distn. residue“ according to GHS/CLP were not met.

The respiratory sensitisation of the test item was not tested.

Thus, the substance is not classifiable for skin or respiratory sensitisation according to GHS / CLP (Regulation EC 1272/2008).