1,4-Cyclohexanedicarboxylic acid, 1,4-bis[2-(2-ethoxyethoxy)ethyl] ester

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

September 04 - November 07, 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study has been performed according to OECD and/or EC guidelines and according to GLP principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Test material

Test material information

Constituent 1

Reference substance name:

1,4-bis[2-(2-ethoxyethoxy)ethyl] cyclohexane-1,4-dicarboxylate

EC Number:

618-829-7

Cas Number:

922165-31-9

Molecular formula:

C20H36O8

IUPAC Name:

1,4-bis[2-(2-ethoxyethoxy)ethyl] cyclohexane-1,4-dicarboxylate

Details on test material:

- Name of test material (as cited in study report): CH-CA
- Appearance: Colorless liquid
- Storage condition of test material: Room temperature in airtight container
- Stability under storage conditions: Unknown

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

male

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Producer: Jung-Ang Lab. Animal Co., Ltd., Seoul, Korea
- Age at study initiation: 5 weeks
- Weight at study initiation: 304-402 g
- Housing: Animals were individually housed in labeled stainless steel wire cages (height 18 cm).
- Diet (e.g. ad libitum): Free access to Purina experimental diet for guinea-pig 5065 (Lot no. KSN:08:01:LNS, KSN:08:22:CMS, KSN:09:15:CMS from Agribrandts Purina Korwa, Inc.).
- Water (e.g. ad libitum): Free access to tap water.
- Acclimation period: The acclimatization period was 12 days before the start of treatment under laboratory conditions.
- Health inspection: Upon receipt of animals, all animals were given veterinary quarantine. During the acclimation period, animals were observed for clinical signs once a day.

The diet was analyzed periodically by the manufacturer. Upon receipt of the certificate from the manufacturer, the contaminants in the diet were checked twice a year in Korea Testing and Research Institute for Chemical Industry. These results of all analytical items were confirmed within the range of the contaminant limit set in Biotoxtech Co., Ltd.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.4 – 23.1ºC
- Humidity (%): 43.9 - 63.1%
- Washing and sterilization of cages, fodder tub, water bottles and animal room:
Cages, fodder tub and water bottles: MICRO QUAT (400 fold, component: Alkyldimethylbenzyl ammonium chloride, ECOLAB, Inc. Korea) solution was used to wash cages, fodder tub and water bottles. A cage, fodder tub and water bottle were replaced once a week.
Disinfections of the animal room: After the daily work, Pacom - A (component: Octyldecyl dimethyl ammonium chloride, 200 fold, SAMU MEDIAN Co., Ltd., Kora), MICRO-QUAT (component: Alkyldimethyl-benzyl ammonium chloride, 400 fold, ECOLAB Co., Ltd., Korea) and BROMO-SEPT (component : Di-decyl di-methyl ammonium bromide, 300 fold, DAE SUNG MICROBIOLOGICAL LABS. Co., Ltd., Korea) solutions were used to disinfect the animals room. Three antiseptic solutions were replaced every 10 days (respectively).
- Air changes (per hr): 10-15 air changes per hour (all fresh air method)
- Photoperiod (hrs dark / hrs light): 12 hours light and 12 hours darkness per day. Intensity of illumination 150-300 Lux.

IN-LIFE DATES: From: September 19 to October 10, 2006

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

other: 1,3-butylene glycol (1,3-BG)

Induction 2

Concentration / amount:

50% test substance for the intradermal induction.
100% test substance for the epicutaneous induction and the challenge exposure.

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

other: 1,3-butylene glycol (1,3-BG)

Challenge 2

Concentration / amount:

50% test substance for the intradermal induction.
100% test substance for the epicutaneous induction and the challenge exposure.

No. of animals per dose:

Test substance group 10 animals, vehicle group 5 animals.

Details on study design:

RANGE FINDING TESTS:
Concentrations: 100, 50, 25, 12.5, 6.25 and 3.13% (v/v) with 1,3-BG were used for intradermal and topical application.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: one intradermal (day 0) and one topical (day 7, 48h).
- Exposure period: 24 h topical induction. SDS was applied to the application site.

B. CHALLENGE EXPOSURE
- No. of exposures: 1 topical
- Day(s) of challenge: 2 weeks after last induction.
- Exposure period: 24 hours.
- Site: The left and right flanks
- Evaluation (hr after challenge): 24 and 48 hours

Positive control substance(s):

yes

Remarks:

every 6 months 1-chloro-2,4-dinitrobenzene

Study design: in vivo (LLNA)

Statistics:

Scores and raw data such as body weights were not statistically analyzed, but mean values were calculated

Results and discussion

Positive control results:

The six-month reliability check with CDNB (1 -Chloro-2,4 -Dinitrobenzene) indicates that the Maximization test as performed at BIotoxtech is an appropriate model for testing for contact hypersensitivity. See the document 'Reliability check' in the attached background material.

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

First induction: 50% test substance, second induction: 100% test substance; Challenge: 100% test substance

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

There were no detectable clinical signs in all animals in relation to the test substance.

Remarks on result:

other: see Remark

Remarks:

Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: First induction: 50% test substance, second induction: 100% test substance; Challenge: 100% test substance. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: There were no detectable clinical signs in all animals in relation to the test substance. .

Results 2

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

100% 1,3-BG

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

There were no detectable clinical signs in all animals. All animals survived to the scheduled observation period.

Remarks on result:

other: see Remark

Remarks:

Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 100% 1,3-BG. No with. + reactions: 0.0. Total no. in groups: 5.0. Clinical observations: There were no detectable clinical signs in all animals. All animals survived to the scheduled observation period..

Results 3

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

First induction: 50% test substance, second induction: 100% test substance; Challenge: 100% test substance

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

There were no detectable clinical signs in all animals in relation to the test substance. All animals survived to the scheduled observation period.

Remarks on result:

other: see Remark

Remarks:

Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: First induction: 50% test substance, second induction: 100% test substance; Challenge: 100% test substance. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: There were no detectable clinical signs in all animals in relation to the test substance. All animals survived to the scheduled observation period..

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

100% 1,3-BG

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

There were no detectable clinical signs in all animals. All animals survived to the scheduled observation period.

Remarks on result:

other: see Remark

Remarks:

Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 100% 1,3-BG. No with. + reactions: 0.0. Total no. in groups: 5.0. Clinical observations: There were no detectable clinical signs in all animals. All animals survived to the scheduled observation period..

Any other information on results incl. tables

Tables of the Main study have been included in the document "Sensitization tables" in the attached background material.

Results Pre-screen test:

Intradermal: in 24 and 48 hours after treatment, each evaluated concentrations showed following skin reactions as intense redness and necrosis (score 3) in 2/2 guinea pigs at 100% concentration; moderate redness (score 2) in 2/2 guinea pigs at 50 and 25% concentrations; moderate (score 2) and mild redness (score 1) in 1/2 guinea pig each at 12.5% concentration; mild redness at 6.25% and 3.13%. Thus, 50% was used (highest to cause irritation but not adversely affecting the animals).

Topical: at 24 and 48 hours after the patch removal, there were no skin reactions.

In addition, the highest concentration for the topical induction and challenge were decided as 100% since there was no skin reaction after the patch removal for all concentrations.

Other results - main study:

There were no detectable clinical signs in all animals. All animals survived to the scheduled observation period.

 

The body weights were normally increased in all test groups during the observation period (the averages of increased body weights were 182 g and 175 g in test substance group and vehicle group, respectively).

 

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

In a guinea pig maximization test performed according to OECD 406 and GLP, CH-CA showed no skin sensitising properties in guinea pigs.