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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Some information in this page has been claimed confidential.

Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
31 December 2018 - 06 February 2019
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2019
Report date:
2019

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
no
GLP compliance:
yes
Type of study:
Buehler test
Justification for non-LLNA method:
We have found the Buehler test to generate more consistent results with the occurrance of fewer false positives for similar UVCB chemistries with surface active properties.

Test material

Constituent 1
Test material form:
semi-solid (amorphous): gel

In vivo test system

Test animals

Species:
guinea pig
Strain:
Hartley
Sex:
male
Details on test animals and environmental conditions:
Animals
Number of Animals: 35
Number of Groups: 3
Number of Animals per Group:

Preliminary Irritation Group: 5 Test Group: 20
Naive Control Group: 10
Sex: Male
Species/Strain: Guinea pigs/Hartley albino.

Age/Body Weight: Preliminary Irritation Group: Young adult
Test and Naive Control Groups: Young adult/525-686 grams at experimental start.
Source: Received from Elm Hill Breeding Labs on November 7 and 21, 2018 (Preliminary Irritation Group) and December 5, 2018 (Test and Naive Control Groups).

METHODS
Husbandry
Housing: The animals were group housed in suspended stainless steel perforated bottom caging, which conforms to the size recommendations in the most recent Guide for the Care and Use of Laboratory Animals (Natl. Res. Council, 2011). Enrichment (e.g., tunnel) was placed in each cage and litter paper was changed at least three times per week.
Animal Room Temperature and Relative Humidity Ranges: 19-23°C and 31-69%, respectively.
Animal Room Air Changes/Hour: 12. Airflow measurements are evaluated regularly and the records are kept on file at Product Safety Labs.
Photoperiod: 12-hour light/dark cycle
Acclimation Period: 34-64 days
Food: PMI Guinea Pig Lab Diet® #5025. A designated amount of diet (approximately 20 grams/day) and Alfalfa Timothy Hay Cubes (Standlee Premium Western Forage) were available to each guinea pig.
Water: Filtered tap water was supplied ad libitum.
Contaminants: There were no known contaminants reasonably expected to be found in the food or water at levels which would have interfered with the results of this study. Analyses of the food and water are conducted regularly and the records are kept on file at Product Safety Labs.

Study design: in vivo (non-LLNA)

Induction
Route:
epicutaneous, occlusive
Vehicle:
other: mieral oil
Concentration / amount:
70%/0.4 mL
Day(s)/duration:
Once each week for three weeks
Adequacy of induction:
highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
Challengeopen allclose all
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4 mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#3
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4 mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#4
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/ 0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#5
Route:
epicutaneous, occlusive
Vehicle:
other: minerl oil
Concentration / amount:
60%/0.4 mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#6
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/ 0.4 mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#8
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4 mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#9
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/ 0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#10
Route:
epicutaneous, occlusive
Vehicle:
other:
Concentration / amount:
60%/0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#11
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#12
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#13
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#14
Route:
epicutaneous, occlusive
Vehicle:
other:
Concentration / amount:
60%/0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#15
Route:
epicutaneous, occlusive
Vehicle:
other:
Concentration / amount:
60%/0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
No.:
#16
Route:
epicutaneous, occlusive
Vehicle:
other:
Concentration / amount:
60%/0.4 mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#17
Route:
epicutaneous, occlusive
Vehicle:
other:
Concentration / amount:
60%/0.4 mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#18
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4 mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#19
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No.:
#20
Route:
epicutaneous, occlusive
Vehicle:
other: mineral oil
Concentration / amount:
60%/0.4mL
Day(s)/duration:
Twenty-seven days after the first induction dose and observed 24 and 48 hours after challenge
Adequacy of challenge:
highest non-irritant concentration
No. of animals per dose:
20
Details on study design:
Preparation of Test Substance
Prior to use, the test substance as received and all prepared concentrations were mixed well. Solubility testing conducted by PSL determined that the test substance was soluble in mineral oil.

Preliminary Irritation Testing
A group of animals was used to determine the highest non-irritating concentration (HNIC) of the test substance prior to the challenge dose. The fur was removed by clipping the flanks of each guinea pig. This area was divided into four test sites (two sites on each side of the midline) on each animal. The test substance was applied neat (100%) and also mixed with mineral oil to yield w/w concentrations of 75%, 70%, 65%, 60%, 55%, 50% and 25%. Each concentration was applied (0.4 mL each) to a test site using an occlusive 25 mm Hill Top Chamber. The sites were wrapped with non-allergenic Durapore adhesive tape. After 6 hours of exposure, the chambers were removed and the test sites were gently cleansed with a 3% soap solution followed by tap water and a clean paper towel to remove any residual test substance. Approximately 24 hours after application, each site was evaluated for local reactions (erythema).
From these results, the HNIC (the highest concentration that produced responses in 4 guinea pigs no more severe than two scores of 0.5 and two scores of zero) was established and used for challenge. The HNIC selected for the challenge phase was a 60% w/w mixture in mineral oil.

Preparation and Selection of Animals
Within 24 hours prior to each application, the fur of a group of animals was removed by clipping the flanks. After clipping and prior to initiation, the animals were weighed and the skin was checked for any abnormalities. Only healthy, naive animals (not previously tested) without pre­ existing skin irritation were selected for test. Animals were re-clipped prior to each dose.

Induction Phase
Once each week for three weeks, four-tenths of a milliliter of a 70% w/w mixture of the test substance in mineral oil was applied to the left side of each test animal using an occlusive 25 mm Hill Top Chamber. The chambers were secured in place and wrapped with non-allergenic Durapore adhesive tape to avoid dislocation of the chambers and to minimize loss of the test substance for six hours. After the 6-hour exposure period, the chambers were removed and the test sites were gently cleansed with a 3% soap solution followed by tap water and a clean paper towel to remove any residual test substance. Approximately 24 and 48 hours after each induction application, readings were made of local reactions (erythema) according to the scoring system described in Section 5.F. Due to the severity of irritation noted at the test sites following the second induction, the dose sites were relocated to adjacent naive areas for the third induction.

Challenge Phase
Twenty-seven days after the first induction dose, four-tenths of a miHiliter of a 60% w/w mixture of the test substance in mineral oil (HNIC) was applied to a naive site on the right side of each animal as a challenge dose, using the procedures described above. These sites were evaluated for a sensitization response (erythema) approximately 24 and 48 hours after the challenge application according to the system described in Section 5.F.
In addition to the test animals, 10 guinea pigs from the same shipment were maintained under identical environmental conditions and were treated with the HNIC of the test substance at challenge only. These animals constituted the "naive control" group.

Scoring System
0 - no reaction
0.5 - very faint erythema, usually non-confluent*
1 - faint erythema, usually confluent
2 - moderate erythema
3 - severe erythema with or without edema
*Very faint erythema is not considered a positive reaction

Body Weights
Individual body weights of the animals were recorded prior to initial induction and again on the day after challenge or after death.

Observations
All preliminary, test, and control animals were observed for general viability during daily room checks.

Study Termination
Once testing was complete, the animals were released for euthanasia and humanely euthanized.

EVALUATION
In order to evaluate the sensitization response at challenge, two indices were used: one for incidence and one for severity (Ritz, H. and Buehler, E., 1980) in the test and naive control animals.
The incidence index is the ratio of animals with erythema scores greater than 0.5 per number of animals evaluated, and is presented for both the 24 and 48-hour intervals after challenge evaluation as follows:
Incidence Index= Number of erythema scores greater than 0.5 / Number of animals evaluated
The severity index is the mean erythema score, and is calculated for both the 24 and 48-hour intervals after challenge

HISTORICAL POSITIVE CONTROL VALIDATION STUDY
The procedures used in this study were validated using Hexyl Cinnamic Aldehyde (HCA) as a positive control substance. The most recent validation, PSL Study #49391, and testing was performed by PSL between November 29, 2018 - January 18, 2019. The raw data and report for this study are archived in PSL Historical Data Notebook No. 49391: pages 1-23. This test was conducted at the Dayton Facility with Hartley strain albino guinea pigs from Elm Hill Breeding Labs

Induction Phase
Historical Positive Control Animals (100% HCA): Very faint to faint erythema (0.5-1) was noted at nine positive control sites during the induction phase.

Challenge Phase
Historical Positive Control Animals (100% HCA): Five of ten positive control animals exhibited signs of a sensitization response (faint erythema [1]) 24 hours after the challenge application. Positive responses persisted at all five positive control sites through 48 hours. Very faint erythema (0.5) was noted at three other sites 24 and 48 hours after challenge application.
Historical Naive Control Animals (100% HCA): Very faint erythema (0.5) was noted at two of five naive control sites 24 hours after challenge application, which resolved by 48 hours.
Challenge controls:
10
Positive control substance(s):
yes
Remarks:
The procedures used in this study were validated using Hexyl Cinnamic Aldehyde (HCA) as a positive control substance. The most recent validation, PSL Study #49391, and testing was performed by PSL between November 29, 2018 - January 18, 2019.

Results and discussion

Positive control results:
Induction Phase
Historical Positive Control Animals (100% HCA): Very faint to faint erythema (0.5-1) was noted at nine positive control sites during the induction phase.

Challenge Phase
Historical Positive Control Animals (100% HCA): Five of ten positive control animals exhibited signs of a sensitization response (faint erythema [1]) 24 hours after the challenge application. Positive responses persisted at all five positive control sites through 48 hours. Very faint erythema (0.5) was noted at three other sites 24 and 48 hours after challenge application.

In vivo (non-LLNA)

Resultsopen allclose all
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
60%
No. with + reactions:
20
Total no. in group:
20
Clinical observations:
no notable adverse clinical reactionis
Remarks on result:
positive indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
60%
No. with + reactions:
20
Total no. in group:
20
Clinical observations:
no notable clinical reactions
Remarks on result:
positive indication of skin sensitisation

Applicant's summary and conclusion

Interpretation of results:
Category 1 (skin sensitising) based on GHS criteria
Conclusions:
Based on these findings and on the evaluation system used, test item is considered to be a contact sensitizer.
The positive response observed in the historical positive control validation study with 25% Hexyl Cinnamic Aldehyde (HCA) validates the test system used in this study
Executive summary:

A dermal sensitization test was conducted with guinea pigs to determine the potential for the test material to produce sensitization after repeated topical applications.

A 70% w/w mixture of the test substance in mineral oil was topically applied to twenty healthy test guinea pigs, once each week for a three-week induction period. Twenty-seven days after the first induction dose, a challenge dose of the test substance at its highest non-irritating concentration (HNIC, determined in the preliminary irritation screen to be a 60% w/w mixture in mineral oil) was applied to a naive site on each guinea pig. A naive control group (ten animals) was maintained under the same environmental conditions and treated with the test substance at challenge only. Approximately 24 and 48 hours after each induction and challenge dose, the animals were scored for erythema.

Based on the findings and on the evaluation system used, test item is considered to be a contact sensitizer.