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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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:
22 Jun 2018 - 02 Nov 2018
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
The study was conducted within the OECD guideline and followed GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report date:
2018

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Version / remarks:
1992
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method B.6 (Skin Sensitisation)
Version / remarks:
2008
Deviations:
no
Qualifier:
according to guideline
Guideline:
EPA OPPTS 870.2600 (Skin Sensitisation)
Version / remarks:
2003
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
In vitro methods for assessing sensitisation potential are available but cannot yet fully substitute the animal tests. The sensitivity and reliability of the experimental technique is assessed on a regular basis using mercaptobenzothiazole, which is recommended by the OECD 406 and is known to have moderate skin sensitisation properties.

Test material

Constituent 1
Chemical structure
Reference substance name:
Octadecyl docosanoate
EC Number:
246-115-1
EC Name:
Octadecyl docosanoate
Cas Number:
24271-12-3
Molecular formula:
C40H80O2
IUPAC Name:
octadecyl docosanoate

In vivo test system

Test animals

Species:
guinea pig
Strain:
other: Crl: HA - Guinea Pigs (full barrier)
Sex:
male
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River, 97633 Sulzfeld, Germany
- Females (if applicable) nulliparous and non-pregnant: Yes
- Microbiological status of animals, when known: Not reported
- Age at study initiation: 5 - 6 weeks
- Weight at study initiation: 330 - 376 g
- Housing: The animals were kept in groups in Terluran - cages on Altromin saw fibre bedding
- Diet (e.g. ad libitum): Free access to autoclaved hay and to Altromin 3122 maintenance diet
- Water (e.g. ad libitum): Free access to mains tap water
- Acclimation period: At least 5 days
- Indication of any skin lesions: No

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3 °C
- Humidity (%): 55 +/- 10%
- Air changes (per hr): At least 10 changes/ hour
- Photoperiod (hrs dark / hrs light): 12 h: 12 h (light: dark)
- IN-LIFE DATES: Not reported

Study design: in vivo (non-LLNA)

Induction
Route:
intradermal
Vehicle:
cotton seed oil
Concentration / amount:
10 mL (w/v).
Day(s)/duration:
48 hours
Adequacy of induction:
highest technically applicable concentration used
Challenge
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
cotton seed oil
Concentration / amount:
10 mL (w/v).
Day(s)/duration:
24 hours
Adequacy of challenge:
highest non-irritant concentration
No. of animals per dose:
10
Details on study design:
RANGE FINDING TESTS: 
1 animal was treated intradermally with concentrations of 0.75% and 0.5% of the test item suspended with cotton seed oil
1 animal was treated topically with concentrations of 40% and 60% of the test item suspended with cotton seed oil for 24 hours
1 animal was treated topically with concentrations of 60% and 60% of the test item suspended with cotton seed oil for 24 hours
1 animal was treated topically with concentrations of 60% and 60% of the test item suspended with cotton seed oil for 48 hours

MAIN STUDY
 A. INDUCTION EXPOSURE
 - No. of exposures: 2
 - Exposure period: 48 hours
 - Test groups: 10 animal
 - Control group: 5
 - Site: shoulder region
- Frequency of applications: 3
 - Duration: 48 hours
 - Concentrations: 60%
 
 B. CHALLENGE EXPOSURE
 - No. of exposures: 1
 - Day(s) of challenge: 21
 - Exposure period: 24 hours
 - Test groups: 10 animals
 - Control group: 5 animals
 - Site: The flanks
- Concentrations: 60%
 - Evaluation (hr after challenge): 24 & 48 hours
 
 OTHER: n/a
Challenge controls:
yes
Positive control substance(s):
yes
Remarks:
mercaptobenzothiazole, purity > 98%, Sigma-Aldrich, lot no.: BCBS4978V, expiry date: 09/2020: 2% induction I phase, 25% induction II phase, 15% challenge

Results and discussion

In vivo (non-LLNA)

Resultsopen allclose all
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
60%
No. with + reactions:
0
Total no. in group:
5
Clinical observations:
none
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
60%
No. with + reactions:
0
Total no. in group:
5
Clinical observations:
None
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
60%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
None
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
60%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
None
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Dose level:
80%
No. with + reactions:
7
Total no. in group:
10
Clinical observations:
Erythema grade 1 and 2
Remarks on result:
positive indication of skin sensitisation
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
positive control
Dose level:
80%
No. with + reactions:
7
Total no. in group:
10
Clinical observations:
Erythena grade 1 and 2
Remarks on result:
positive indication of skin sensitisation

Any other information on results incl. tables

Table 2. Challenge Exposure

Challenge Concentrations of Test Substance: 60%

 

Number of Animals Showing Skin Reactions after

24 hours

48 hours

Test group

0

0

Negative- control group

0

0

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
Neither erythema nor oedema was observed in any animal at any time of observation. There was no evidence of sensitisation and the percentage of sensitised animals was 0%. Under the conditions of the present study it can be stated that the test item Octadecyl docosanoate caused no reactions identified as sensitisation at the tested concentration.  According to Commission Regulation (EU) No 286/2011 as well as GHS (Globally Harmonized Classification System), the test item Octadecyl docosanoate has no obligatory labelling requirement for skin sensitisation and is unclassified.
Executive summary:

OECD 406 - 2018: In a preliminary study 4 animals were treated with the test item suspended in cotton seed oil; animal 1 treated intradermally with concentrations of 0.75% and 0.5%, animal 2 treated topically with concentrations of 40% and 60% for 24 hours , animal 3 treated topically with concentrations of 60% and 60% for 24 hours and animal 4 treated topically with concentrations of 60% and 60% for 48 hours.

The concentration of 0.75% caused slight signs of irritation, without leading to systemic effects. The dermal application of 60% did not cause signs of irritation or systemic effects after a treatment period of 48 hours and was chosen for topical induction.  A concentration of 60% was found to be the highest tested dose which did not cause any signs of irritation after a topical treatment over a period of 24 hours and therefore was chosen for the challenge application in the main test. 


Based on the results of this preliminary test, a concentration of 0.75% was chosen for the intradermal application of the main test and a concentration of 60% was selected for the dermal induction. 


Main experiment:

Induction: First Stage, Intradermal Injection

Three pairs of intradermal injections of 0.1 mL volume were given in the clipped shoulder region;




Test Group: Day 0

Injection 1: a 1:1 mixture (v/v) FCA / physiological saline 0.9% NaCl

Injection 2:a 0.75% concentration of the test item in cottonseed oil  

Injection 3: a 0.75% concentration of the test item formulated in a 1:1 mixture (v/v) FCA / physiological saline 0.9% NaCl

Control Group: Day 0

Injection 1:  1:1 mixture (v/v) FCA / physiological saline 0.9% NaCl

Injection 2:  a 100% cottonseed oil

Injection 3: a 50% (v/v) formulation of cottonseed oil in a 1:1 (v/v) mixture FCA / physiological saline 0.9% NaCl

Induction: Second Stage, Topical Application

Test Group Day 7: The test item was suspended with cottonseed oil at a concentration of 60%. A patch was fully loaded with 0.5 mL of the prepared test item. Then it was applied to the test area and held in contact with the help of an occlusive dressing for 48 hours.

Control Group Day 7: A patch was fully loaded with 0.5 mL of cottonseed oil. Then it was applied to the test area and held in contact with the help of an occlusive dressing for 48 hours.

Challenge: Topical Application

Test Group and Control Group: Day 21

The test item was suspended with cottonseed oil at a concentration of 60%. A patch loaded with 0.5 mL of the prepared test item was applied to the left flank of the animals and a patch loaded with 0.5 mL of the vehicle to the right flank (intraspecific control). The patches were held in contact with the help of an occlusive dressing for 24 hours. The application area was not rinsed.

Approximately 21 hours after removing the patch, the challenge area was cleared of hair by the use of a depilatory cream. Approximately 24 and 48 hours after removing the patch the skin reaction was observed and recorded according to the grades shown below.

Additionally all animals were observed for signs of toxicity at least once daily during the test period.

Result:

All animals survived throughout the study. One control animal exhibited clinical signs such as moderately reduced spontaneous activity, scratches on the back, a bite wound on the neck and residual dirt around the eyes on study day 7. Slightly reduced spontaneous activity and residual dirt around the eyes was observed on study day 8. Scratches on the back were noted from day 7 to day 16, a bite wound on the neck observed from day 7 to day 11 was replaced by crust on the neck from day 12 to day 16 of the study. From study day 17 no clinical signs were observed any more. 


Body weight development was within the expected range for all  animals.

Grade 1 erythema and oedema was observed in both control and treated animals during induction phase, this was considered effect of dressing not treatment related.

Neither erythema nor oedema was observed in any animal at any time of observation. There was no evidence of sensitisation and the percentage of sensitised animals was 0%.

Conclusion:

Under the conditions of the present study it can be stated that the test item Octadecyl docosanoate caused no reactions identified as sensitisation at the tested concentration.  According to Commission Regulation (EU) No 286/2011 as well as GHS (Globally Harmonized Classification System), the test item Octadecyl docosanoate has no obligatory labelling requirement for skin sensitisation and is unclassified.