2-Propyn-1-ol, reaction product with 1-2.5 moles of oxirane

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study, Source substance for RA information according to analogue justification.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

Reaction product of 2-Propyn-1-ol with methyloxirane

EC Number:

609-530-2

Cas Number:

38172-91-7

IUPAC Name:

Reaction product of 2-Propyn-1-ol with methyloxirane

Details on test material:

- Physical state: liquid
- Analytical purity: 54.7 area %
- Impurities (identity and concentrations): 33.9 g/100 g water, propargyl alcohol 0.6 area %, propylene glycol 5.3 area %, higher alcoxylated products 5.4 area %
- Lot/batch No.: 88767924U0
- Stability under test conditions: The stability of the test item under storage conditions over the study period was guaranteed by the sponsor,
and the sponsor holds this responsibility.
- Storage condition of test material: Room temperature

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories B.V.
- Age at study initiation: 10-11 weeks (beginning of treatment)
- Weight at study initiation: animals of comparable size and weight
- Housing: group housing
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: At least 5 days prior to the start of dosing

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +-2
- Humidity (%): 45 – 65%
- Air changes (per hr): ca. 10/h
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

dimethylformamide

Concentration:

25 %, 50 % and 100 %

No. of animals per dose:

5

Details on study design:

RANGE FINDING TESTS:
At the tested concentrations (50 % and 100 %) the animals did not show any signs of systemic toxicity. On days 3 and 4, both treated animals showed an erythema of the ear skin (Score 1). Other signs of irritation or signs of systemic toxicity were not observed.
Thus, the test item in the main study was assayed at 25, 50% (w/w), and 100%.

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: OECD 429
- Criteria used to consider a positive response:
A test item is regarded as a sensitiser in the LLNA if the following criteria are fulfilled:
- First, 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.
- Second, 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:
Each test group of mice was treated by topical (epidermal) application to the dorsal surface of each ear with test item concentrations of 25, 50% (w/w), and 100% in dimethylformamide. The application volume, 25 μL/ear/day, was spread over the entire dorsal surface 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.

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, for the ear weights, the lymph node weights and lymph node cell count, and for the DPM values (group mean DPM ± standard deviation).
A statistical analysis was conducted on the DPM values, the ear weights, the lymph node weights and the lymph node cell count to assess whether the difference was statistically significant between test item groups and negative control group. For all statistical calculations SigmaStat for Windows (Version 2.0) was used. A One-Way-Analysis-of-Variance was used as statistical method. In case of significant results of the One-Way-ANOVA, multiple comparisons were performed with the Dunnett test or the Student Newman Keuls test. Statistical significance was set at the five per cent level (p < 0.05). The Dean-Dixon-Test and/or Grubb’s test was /were used for identification of possible outliers (performed with Microsoft Excel 2003).
However, both biological and statistical significance were considered together.

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: S.I. control: 1.0 25 %: 0.60 50 %: 1.14 100 %: 0.71

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: Vehicle: 742.3 dpm 25 %: 445.3 dpm 50 %: 844.5 dpm 100 %: 524.1 dpm

Any other information on results incl. tables

Viability / Mortality

No deaths occurred during the study period.

Clinical Signs

No symptoms of local toxicity at the ears of the animals and no systemic findings 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.

Lymph Node Weights and Cell Counts

The measured lymph node weights and –cell counts of all animals treated were recorded after sacrifice. A statistically significant or biologically relevant increase in lymph node weights was not observed in any of the test item treated groups in comparison to the vehicle control group. For BALB/c mice, a cutoff-value for the lymph node cell count index of 1.55 was reported for a positive response. The indices determined for the lymph node cell count did not exceed this threshold.

Ear Weights

The measured ear weights of all animals treated were recorded after sacrifice. A statistically significant or biologically relevant increase in ear weights was not observed in any treated group in comparison to the vehicle control group.

For BALB/c mice, a threshold for the ear weight index of 1.1 was reported for a positive response. The indices determined for the lymph node cell count did not exceed this threshold. Furthermore, according to OECD guideline 429, an increase in ear weight exceeding the threshold value of 25% was considered to be indicative for excessive local skin irritation. This threshold was not exceeded in any test item treated group.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Executive summary:

In order to study a possible skin sensitisation potential of 2-Propyn-1-ol, compd. with methyloxirane, 3 groups each of 5 female mice were treated once daily with the test item at concentrations of 25, 50% and 100% in dimethylformamide by topical application to the dorsum of each ear for three consecutive days according to OECD 429 in compliance with GLP.

A control group of 5 mice was treated with the vehicle (dimethylformamide) only. All treated animals survived the scheduled study period and no signs of systemic toxicity or local skin irritation were observed. 

The Stimulation Indices (S.I.) of 0.60, 1.14, and 0.71 were determined with the test item at concentrations of 25, 50% (w/w) and 100% in dimethylformamide, respectively. An outlier was identified in the mid dose group but it did not change the overall test result and was not excluded from calculation.A statistically significant increase in DPM value, lymph node weight and also in lymph node cell count was not observed in any of the tested dose groups in comparison to the vehicle control group. Furthermore, the cutoff-value for a positive response regarding the lymph node cell count index of 1.55 reported for BALB/c mice was not exceeded in any dose group.

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

The test item 2-Propyn-1-ol, compd. with methyloxirane was not a skin sensitiser under the test conditions of this study (BASF, 2012).