reaction products of 1,4-butanediol with 1,3-chloro-2,3-epoxypropane, esters with prop-2-enoic acid

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:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted April 2002

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.42 (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 products of butane-1,4-diol and 1-chloro-2,3-epoxypropane, esters with acrylic acid

EC Number:

701-230-0

Cas Number:

52408-42-1

Molecular formula:

C16H26O8

IUPAC Name:

Reaction products of butane-1,4-diol and 1-chloro-2,3-epoxypropane, esters with acrylic acid

Test material form:

liquid

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/Ca

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: B & K Universal Ltd, Hull, UK and Charles River UK Limited
- Age at study initiation: 8 - 12 weeks
- Weight at study initiation: 15 - 23g
- Housing: single in suspended solid-floor polypropylene cages
- Diet (e.g. ad libitum): certified rat and mouse diet (code 5LF2) ad lib.
- Water (e.g. ad libitum): tap water ad lib.
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 - 25°C
- Humidity (%):30 - 70%
- Air changes (per hr): app. 15
- Photoperiod (hrs dark / hrs light): 12h/12h

Study design: in vivo (LLNA)

Vehicle:

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

Concentration:

5%, 10%, 25% (v/v)

No. of animals per dose:

4

Details on study design:

RANGE FINDING TESTS:
- concentrations: 25%, 50%, 100% (1 animal per dose)
- Irritation: redness between the ears at 25%
- signs of toxicity only noted at 50%: hunched posture, lethargy, piloerection, ptosis and laboured respiration

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Criteria used to consider a positive response: at least one concentration of the test material must results in a threefold or greater increase in 3HTdR incorporation compared to contral values.

TREATMENT PREPARATION AND ADMINISTRATION:
The mice were treated by daily application of 25µl per ear (50µl total) of the appropriate concentration of the test material for three consecutive days. The test material formulation was administered using an automatie micropipette and spread over the dorsal surface of the ear using the tip of the pipette. Five days following the first topical application of the test material all mice were injected via the tail vein with 250µl of phosphate buffered saline (PBS) containing 3H-methyl thymidine. Five hours later, the mice were killed by carbon dioxide asphyxiation and the auricular lymph nodes were excised and pooled per experimental group.

Positive control substance(s):

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

Results and discussion

Positive control results:

sensitizing (SI = 5.07) at 50%

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Value:

4.28

Remarks on result:

other: 5%

Results 2

Parameter:

SI

Value:

4.14

Remarks on result:

other: 10%

Results 3

Parameter:

SI

Value:

7.32

Remarks on result:

other: 25%

Cellular proliferation data / Observations:

DPM :
vehicle: 8868.46
5%: 37933.26
10%: 36740.79
25%: 64912.78

Any other information on results incl. tables

No signs of systemic toxicity were observed. The body weight increased as expected.

Moderate redness was noted between the ears in animals treated with 10% and 25% of the test substance.

Applicant's summary and conclusion

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

The test material was considered a sensitizer under the conditions of the test at all concentrations tested (5%, 10%, 25%). Signs for irritation were only observed at the two highest concentrations.

Executive summary:

A local lymph node assay in the mouse was performed on butane-1,4-diylbis(oxy-2-hydroxypropane-3,1-diyl) bisacrylate to assess the skin sensitization potential of the substance in the CBA/Ca strain mouse following topical application to the dorsal surface of the ear. The study was performed according to the OECD guideline 429 (2002).

Following a preliminary screening test, three groups, each of four animals, were treated with 50 µl (25 µl per ear) of the test material as a solution in acetone/olive oil 4:1 at concentrations of 5%, 10% and 25%. A further group of 4 animals was treated with acetone/olive oil 4:1 alone.

The stimulation index expressed as the mean incorporation for each treatment group divided by the mean radioactive incorporation of the vehicle control group are of 4.28, 4.14 and 7.32 respectively. All the SI were higher than 3, indicating positive results. In conclusion, the test material was considered to be a sensitizer under the conditions of the test.