Alcohols, C11-15-secondary, ethoxylated

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation, other

Remarks:

existing in vivo study

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

12 May to 10 June 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study conducted in accordance with an internationally accepted guideline (OECD)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2016

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

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:

Alcohols, secondary C11-15, ethoxylated

EC Number:

614-295-4

Cas Number:

68131-40-8

Molecular formula:

C(11-15) H(23-31) O (C2H4O)xH where n= approximately 3

IUPAC Name:

Alcohols, secondary C11-15, ethoxylated

Details on test material:

- Name of test material (as cited in study report): Softanol 30
- Physical state: Slightly yellow clear liquid
- Analytical purity: 100%
- Impurities (identity and concentrations): not applicable
- Lot/batch No.: 9G28W1
- Expiration date of the lot/batch: End July 2010
- Storage condition of test material: ca. 4°C in the dark

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
-Source: United Kingdom
- Age at study initiation: approximately 8- 12 weeks
- Weight at study initiation: 17.3 to 22.2 g
- Housing: individually in polycarbonate cages with woodflake bedding.
- Diet (e.g. ad libitum): free access
- Water (e.g. ad libitum): freely available
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 23°C
- Humidity (%): 40 to 70%
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: To: 18 May to 9 June 2010

Study design: in vivo (LLNA)

Vehicle:

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

Concentration:

5, 10 and 25% v/v

No. of animals per dose:

4 females/dose

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: A vehicle trial was conducted and Softanol 30 showed that it formed a clear solution at 50% v/v in acetone:olive oil (4:1 v/v), which was satisfactory for dose administration.
- Irritation: signs of irritation were seen over the dosed area on Days 2 to 4 (100% v/v) and Days 2 and 3 (Group 50%).
- Lymph node proliferation response: no data

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: Pooled treatment group approach
- Criteria used to consider a positive response: the test substance is regarded as a sensitizer if at least one concentration of the test substance
results in a three-fold greater increase in 3HTdR incorporation compared to control values

TREATMENT PREPARATION AND ADMINISTRATION:
- Preliminary test: Three females were treated with one of three concentrations of the test substance. The mice were treated by daily application of 25 μl of appropriate concentration of the test substance to the dorsal surface of each ear for three consecutive days (Days 1-3).
- Main test: Groups of four mice were treated at one of three concentrations of the test substance. The mice were treated by daily application of 25 μl of the appropriate concentration of the test substance to the dorsal surface of each ear for three consecutive days (Days 1-3).
In the main phase of the study, five days following the first topical application of test substance (Day 6) all mice were treated with 250 μl of phosphate buffered saline containing 3H-methyl Thymidinea (3HTdR: 80 μCi/mL) giving a nominal 20 μCi to each mouse.

A single cell suspension of lymph node cells (LNC) was prepared by gentle mechanical disaggregation through a stainless steel gauze (200 mesh size). The pooled LNC were then washed by adding 10 mL phosphate buffered saline, pelleted at 190 x g for 10 minutes and resuspended. The cells were washed twice again and resuspended in 3 mL trichloroacetic acid (TCA: 5%) following the final wash. After overnight incubation with 5% TCA at 4°C, the precipitate was recovered by centrifugation and resuspended in 1 mL 5% TCA and transferred to 10 mL Ultima gold scintillation fluid on Day 7. 3HTdR incorporation was measured by β-scintillation counting.

Results and discussion

Positive control results:

Responses to the positive control substance hexyl cinnamic aldehyde (HCA), in contemporaneous studies demonstrated the reliability and sensitivity of this assay to detect skin sensitization potential in this laboratory.

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: 5% v/v 1.6 10% v/v 1.7 25% v/v 5.1

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: 5% v/v 3994.75 10% v/v 4477.95 25% v/v 13141.35

Any other information on results incl. tables

The test substance is regarded as a sensitizer if at least one concentration of the test substance results in a three-fold greater increase in 3HTdR incorporation compared to control values.

Applicant's summary and conclusion

Interpretation of results:

sensitising

Remarks:

Migrated information

Conclusions:

Softanol 30 is regarded as a potential skin sensitizer.

Executive summary:

In a dermal sensitization study realised according to the OECD guideline 429 and in compliance with GLP (HLS 2010, PLZ0020), Softanol 30 in acetone/olive oil (4:1 v/v) at 5, 10 and 25 % was tested on female CBA mice (4/group), using the LLNA (Local Lymph Node Assay) . 

Animals were treated by daily application of 25µl of the appropriate concentration to the dorsal surface of each ear for 3 consecutive days and all mice were treated with 250 μl of phosphate buffered saline containing 3H-methyl Thymidine (3HTdR: 80 μCi/mL) giving a nominal 20 μCi to each mouse on Day 6.

Stimulation index were 1.6, 1.7 and 5.1 at 5, 10 and 25%. Therefore Softanol 30 is regarded as a potential skin sensitizer.