Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Toxicological information

Skin sensitisation

Currently viewing:

Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
11 August 1994 to 18 September 1994
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1995
Report date:
1995

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Version / remarks:
1981
Deviations:
no
Qualifier:
according to guideline
Guideline:
EPA OPP 81-6 (Skin Sensitisation)
Version / remarks:
1984
Deviations:
no
GLP compliance:
yes
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
Data from existing non-LLNA study available.

Test material

Constituent 1
Chemical structure
Reference substance name:
(R)-2-(4-chloro-2-methylphenoxy)propionic acid
EC Number:
240-539-0
EC Name:
(R)-2-(4-chloro-2-methylphenoxy)propionic acid
Cas Number:
16484-77-8
Molecular formula:
C10H11ClO3
IUPAC Name:
(R)-2-(4-chloro-2-methylphenoxy)propionic acid
Test material form:
solid: flakes
Remarks:
Hard cream/pale brown flakes.
Details on test material:
- Storage conditions: Ambient temperature, in the original container.
Specific details on test material used for the study:
TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The test material was prepared at appropriate concentrations in propylene glycol or in propylene glycol in Freunds Complete Adjuvant. Concentrations of the test material were expressed gravimetrically, in terms of the test material as received. Fresh doses were prepared on the day of administration and any unused material was disposed of on the same day.

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Stability under test conditions: No analyses were undertaken to assess the stability, homogeneity or achieved concentrations of the test material in the vehicles.

In vivo test system

Test animals

Species:
guinea pig
Strain:
Dunkin-Hartley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Females nulliparous and non-pregnant: Not specified
- Age at study initiation: All animals were six to eight weeks of age before treatment on Day 1.
- Weight at study initiation: On Day 1, the bodyweight range of the control animals was 346 - 449 g and of the test animals was 363 - 468 g.
- Housing: Housed in stainless steel cages, with grid floors and tops. The grid floors ensured rapid removal of waste material to undertrays which were cleaned out as necessary. No more than five animals of the same sex were assigned to each cage (animals were allocated to each cage without further selective procedures). The cages were suspended in mobile stainless steel racks.
- Diet: ad libitum access to a commercially available pelleted guinea pig diet.
- Water: ad libitum access to tap water taken from the public supply.
- Acclimation period: An acclimatisation period of at least six days but not more than sixteen days was allowed between arrival at the laboratory and first administration of the test material in the main study. During this period the health of the animals was monitored

ENVIRONMENTAL CONDITIONS
- Temperature: 18 °C (range 15 - 23 °C)
- Humidity: 55 % R.H. (range 40 - 70 %)
- Air changes: 15 air changes per hour without re-circulation.
- Photoperiod: 12 hours of artificial light per day; there was no source of natural light.

Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
intradermal
Vehicle:
propylene glycol
Concentration / amount:
5 % w/v in propylene glycol and 5 % w/v in propylene glycol in FCA
Day(s)/duration:
Treatment on Day 1
Adequacy of induction:
highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
Route:
epicutaneous, occlusive
Vehicle:
propylene glycol
Concentration / amount:
50 % w/v in propylene glycol
Day(s)/duration:
Treatment on Day 8
Adequacy of induction:
highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
Challenge
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
propylene glycol
Concentration / amount:
0.5 and 3 % w/v in propylene glycol
Day(s)/duration:
Treatment on Day 21
Adequacy of challenge:
highest non-irritant concentration
No. of animals per dose:
10 / sex / group
Details on study design:
RANGE FINDING TESTS:
- The study design included a primary skin irritation screen which imposed limits on the challenge concentration of test material used during the main study. The concentrations used for first and second induction were determined during the previous study.
- Topical Challenge Administration
Three guinea-pigs received a single intradermal injection of 0.1 mL FCA 17 days before topical application to simulate the FCA insult that the main study animals receive before challenge application. The hair was removed from both flanks of the three animals. Topical application of 0.03 mL of four concentrations of test material in the selected challenge vehicle was administered to the four test sites on each guinea-pig.
Each test formulation was applied to a 1 cm diameter absorbent patch (A1-test, Imeco AB, Södertälje, Sweden) which was applied to the skin and covered by an occlusive dressing (Blenderm and Elastoplast) for 24 hours.
Reactions to treatment were assessed approximately 24 and 48 hours after removal of the dressings.

MAIN STUDY
A. INDUCTION EXPOSURE
- Primary induction: The induction procedures were primary induction by intradermal injection on Day 1 and secondary induction by occluded topical application on Day 8. Dermal responses to primary and secondary induction were assessed approximately 24 hours and 48 hours after injection or removal of the occlusive dressings.
Three pairs of injections (0.1 mL) were made deep into the dermis, such that on either side of the dorsal median line there were three injection sites in a row parallel to the spinal column. All injection sites lay near the periphery of a dermal test site 4 x 2 cm long, overlying the scapulae. The anterior and middle sites were positioned close together and distant from the posterior sites.
In the test material treatment group, the anterior sites were injected with FCA, the middle sites with the test material in propylene glycol and the posterior sites with the test material in propylene glycol in FCA. In the control group, the anterior sites were injected with FCA, the middle sites with propylene glycol and the posterior sites with propylene glycol in FCA.
- Secondary induction: On Day 8, the dermal sites overlying the scapulae were treated by topical application of 0.6 mL of 50 % w/v test material in propylene glycol to test animals, while controls received 0.6 mL of the vehicle. Each dose was applied to a 4 x 2.5 cm absorbent patch (Whatman No. 3 filter paper) which was applied to the skin and covered by an occlusive dressing (Blenderm and Elastoplast) for 48 hours. The application site was wiped with a paper tissue moistened with the vehicle immediately after removal of the bandage.
- No. of exposures: 2
- Exposure period: 48 h for secondary induction
- Control group: The control animals (Group 1) were treated identically to the test animals (Group 2) during the induction and challenge procedures, except that during induction the test material was replaced by vehicle.

B. CHALLENGE EXPOSURE
- Site: Both flanks of all animals were clipped on Day 21. On Day 22 these areas were wet shaven to reveal a 5 x 10 cm area on the left flank and a 5 x 10 cm area on the right flank. Approximately three hours later the left site was treated by topical application of 0.03 mL of the vehicle while the right side received 0.03 mL of the maximum non-irritant concentration to one site and a dilution to a second site. The doses were applied to 1 cm diameter absorbent patches (A1-test) and covered by an occlusive dressing for 24 hours. The test site was wiped with a paper tissue moistened with vehicle immediately after removal of the bandage.
- Evaluation: The challenge sites were examined approximately 24 and 48 hours after removal of the occlusive dressings.

OTHER:
- Freunds Complete Adjuvant: Freunds Complete Adjuvant (FCA) was prepared immediately before use by emulsifying equal volumes of purified water and the concentrate of the complete adjuvant. The term Freunds Complete Adjuvant or the abbreviation FCA used throughout this RSS refers to a 1:1 mixture of the adjuvant concentrate with purified water. Fresh doses were prepared on the day of administration and any unused material was disposed of on the same day.
- Preparation of animals: An area of skin 4 cm long and 6 cm wide overlying the scapulae was clipped free of hair with electric clippers on the day before treatment commenced.
- Scoring: The presence or absence of erythema or swelling of the treated skin was assessed without knowledge of the number or group identity of the animal under examination. The degree of reaction was scored on a five point scale:
0 = No response
+ = Barely perceptible erythema
1 = Slight erythema
2 = Moderate erythema
3 = Severe erythema
Other reactions to treatment were recorded on an individual basis (present or absent).
Barely perceptible erythema (Grade +) is often a non-specific response to the dosing procedure and is not considered to be a significant or conclusive indication of delayed contact hypersensitivity.
- Bodyweight: The bodyweight of each animal was recorded at weekly intervals to detect treatment-related depression of growth or individual cases of ill-health.
- Termination: All animals were killed at termination of the study, without necropsy.
Positive control substance(s):
no

Results and discussion

In vivo (non-LLNA)

Resultsopen allclose all
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
0.5 w/v in propylene glycol
No. with + reactions:
0
Total no. in group:
20
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
3 % w/v in propylene glycol
No. with + reactions:
0
Total no. in group:
20
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
propylene glycol
No. with + reactions:
0
Total no. in group:
20
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
0.5 % w/v in propylene glycol
No. with + reactions:
1
Total no. in group:
20
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
3 % w/v in propylene glycol
No. with + reactions:
3
Total no. in group:
20
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
propylene glycol
No. with + reactions:
0
Total no. in group:
20
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Remarks on result:
not measured/tested

Any other information on results incl. tables

- Induction: Intradermal administration of 5 % w/v test material in propylene glycol in the adjuvant, caused slight or moderate erythema, pallor and occasional discolouration. Injection of 5 % w/v test material in propylene glycol alone gave rise to a single case of pallor.

Topical application of 50 % w/v test material in propylene glycol caused slight or moderate erythema, oedema, exfoliation and occasional eschar formation, fissuring and loss of elasticity.

 

- Challenge: Challenge application of 3 % w/v test material in propylene glycol caused slight erythema in three control animals and barely perceptible erythema in three test and four control animals. Exfoliation was seen in three test and five control animals. 

Challenge with 0.5 % w/v test material in propylene glycol caused slight erythema in one control animal and barely perceptible erythema in a further control animal; exfoliation was seen in two control animals. No dermal reaction was evident amongst the test animals.

Barely perceptible erythema and exfoliation were seen in two control animals challenged with propylene glycol alone.

 

- General health and bodyweight: The animals remained in overt good health and achieved anticipated overall bodyweight gains. On Day 25, the bodyweight range of the control animals was 503 - 730 g and of the test animals 493 - 695 g.

Applicant's summary and conclusion

Interpretation of results:
other: Not classified according to EU criteria.
Conclusions:
Under the conditions of this study, repeated administration of the test material did not cause delayed contact hypersensitivity in the guinea-pig.
Executive summary:

The potential of the test material to cause delayed contact hypersensitivity in guinea-pigs was assessed by the Magnusson-Kligman Maximisation Test in accordance with the standardised guideline OECD 406 and US EPA OPP 81-6 in compliance with GLP.

The closely-clipped dorsa of ten male and ten female Dunkin-Hartley guinea-pigs were subject to intradermal injections of Freunds Complete Adjuvant, 5 % w/v test material in propylene glycol and 5 % w/v test material in propylene glycol in the adjuvant on Day 1. Seven days later the same area of skin was treated by topical application of 50 % w/v test material in propylene glycol and the test site was covered by an occlusive dressing for 48 hours.

The same induction procedures were carried out on a contemporaneous control group of ten male and ten female animals, except that the test material was replaced by vehicle in all doses.

On Day 22, all animals were challenged by occluded application of propylene glycol to the left flank, and 3 % and 0.5 % w/v test material in propylene glycol to two sites on the right flank. The occlusive dressings were removed on the following day and the condition of the test sites was assessed approximately 24 and 48 hours later.

Intradermal administration of 5 % w/v test material in propylene glycol in the adjuvant, caused slight or moderate erythema, pallor and occasional discolouration. Injection of 5 % w/v test material in propylene glycol alone gave rise to a single case of pallor.

Topical application of 50 % w/v test material in propylene glycol caused slight or moderate erythema, oedema, exfoliation and occasional eschar formation, fissuring and loss of elasticity.

Challenge application of 3 % w/v test material in propylene glycol gave rise to a significant response (slight erythema or a more marked reaction) in no test but three control animals. Challenge with 0.5 % w/v test material in propylene glycol gave rise to a significant response in no test but one control animal only. Challenge application of propylene glycol alone caused no significant response in any animal.

Under the conditions of this study, repeated administration of the test material did not cause delayed contact hypersensitivity in the guinea-pig.