Condensation products of N-(2-aminoethyl)octadecanamide and N-(2-aminoethyl)hexadecanamide with sebacic acid

Endpoint summary

Description of key information

Based on results of this study, the test substance is not Classified as a Skin Sensitiser

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Reference 1

Endpoint:

skin sensitisation: in chemico

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 442C (In Chemico Skin Sensitisation: Direct Peptide Reactivity Assay (DPRA))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

direct peptide reactivity assay (DPRA)

Details on the study design:

The DPRA is an in chemico method, which quantifies the remaining concentration of Cysteine or Lysine containing peptide, following 24 ± 2 hours incubation with the test item at 25 ± 2.5 ºC. The synthetic peptides contain phenylalanine to aid in the detection. Relative peptide concentration is measured by high-performance liquid chromatography (HPLC) with gradient elution and UV detection at 220 nm. Cysteine and Lysine peptide percent depletion values are calculated and used in a prediction model which allow assigning the test item to one of four reactivity classes used to support the discrimination between sensitizers and non-sensitizers.

Positive control results:

Cinnamaldehyde used as positive control (PC) at a concentration of 100 mM in acetonitrile. The results were as expected.

Key result

Run / experiment:

other: DPRA

Parameter:

other: DPRA

Value:

0

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

Due to the low water soulbility of 0.00022mg/L no effect was observed.

Interpretation of results:

other: Water Solubility of <0.00013 mg/l meant it was not possible to test according to DPRA

Conclusions:

Due to the the water solubility of 0.00022 mg/L no depletion of Cysteine or Lycine was observed.

Reference 2

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28 November to 03 December 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Kyoeisha Chemical Co. Ltd. / Lot no. 6021874
- Expiration date of the lot/batch: February 18, 2019
- Purity test date: February 18, 2017

RADIOLABELLING INFORMATION (if applicable)
- Radiochemical purity: 98.94%
- Specific activity: 18000 mCi/mmole
- Locations of the label: 3H Methyl Thymidine
- Expiration date of radiochemical substance: no data

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature in original container away from heat and sunlight.
- Stability under test conditions:
- Solubility and stability of the test substance in the solvent/vehicle:
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium:

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: none
- Preliminary purification step (if any):
- Final dilution of a dissolved solid, stock liquid or gel:
- Final preparation of a solid:

FORM AS APPLIED IN THE TEST (if different from that of starting material)

TYPE OF BIOCIDE/PESTICIDE FORMULATION (if applicable)

OTHER SPECIFICS:
- measurement of pH, osmolality, and precipitate in the culture medium to which the test chemical is added:
- other information:

Species:

mouse

Strain:

CBA:J

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Commercila laboratory animal supplier.
- Females nulliparous and non-pregnant: yes
- Microbiological status of animals, when known:
- Age at study initiation: 10-11 weeks
- Weight at study initiation: Minimum: 21.0 g, Maximum: 26.9 g
- Housing: Solid floor polypropylene mice cages (size: 290 mm x 220 mm x 140 mm). Each cage is fitted with a top grill having provision for keeping rodent pellet feed and water bottles. The bottom of the cages is layered with clean sterilized rice husk as bedding material.
- Diet: Teklad Certified Global High Fiber Rat/Mice Feed manufactured by Envigo, USA, was provided ad libitum.
- Water: UV sterilised water (Reverse Osmosis water filtration system) was provided ad libitum.
- Acclimation period: 6 days
- Indication of any skin lesions: no

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 to 23 °C
- Humidity (%): 59 to 66%
- Air changes (per hr): Minimum 15 air changes/hour
- Photoperiod (hrs dark / hrs light): The photoperiod was 12 h artificial light and 12 h darkness, light hours being 06:00 – 18:00 h (photoperiod maintained through an automatic timer).
- IN-LIFE DATES: From: To:

Vehicle:

dimethylformamide

Concentration:

5%, 10%, 25% and 50%

No. of animals per dose:

8 (2 mice/group) for preliminary assay, and 25 (5 mice/group) for main study

Details on study design:

PRE-SCREEN TESTS:
- Compound solubility: The test item formed a homogenous suspension in dimethylformamide up to 50% (w/v).
- Irritation: nonre
- Systemic toxicity: none
- Ear thickness measurements: yes
- Erythema scores: no data

MAIN STUDY

ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: LLNA
- Criteria used to consider a positive response: A Stimulation Index (SI) value of three or more (SI value of treated group over the control) indicates potential to cause skin sensitisation.

TREATMENT PREPARATION AND ADMINISTRATION: Three groups (G2 to G4) were treated topically for three consecutive days (days 0, 1 and 2) on the dorsal surface of both ears (25 L/ear) using a calibrated micropipette at concentrations of 10%, 25% and 50% (w/v) Reaction mass of N, N’-bis [2-(octadecanoylamino) ethyl] decanediamide and N, N’-bis [2-(hexadecanoylamino) ethyl] decanediamide in dimethylformamide, respectively. Mice from the vehicle control group (G1) and positive control group (G5) were handled in the same manner but received 25 L/ear of dimethylformamide and 25% (v/v) a-Hexylcinnamaldehyde in dimethylformamide, respectively.
Three groups (G2 to G4) were treated topically for three consecutive days (days 0, 1 and 2) on the dorsal surface of both ears (25 L/ear) using a calibrated micropipette at concentrations of 10%, 25% and 50% (w/v) Reaction mass of N, N’-bis [2-(octadecanoylamino) ethyl] decanediamide and N, N’-bis [2-(hexadecanoylamino) ethyl] decanediamide in dimethylformamide, respectively. Mice from the vehicle control group (G1) and positive control group (G5) were handled in the same manner but received 25 L/ear of dimethylformamide and 25% (v/v) a-Hexylcinnamaldehyde in dimethylformamide, respectively.

Positive control substance(s):

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

Positive control results:

Affirmative

Key result

Parameter:

SI

Value:

1

Test group / Remarks:

G1 - Vehicle

Key result

Parameter:

SI

Value:

1.03

Test group / Remarks:

G2 - 10 w/v in DMF

Key result

Parameter:

SI

Value:

1.25

Test group / Remarks:

25% w/v in DMF

Key result

Parameter:

SI

Value:

1.73

Test group / Remarks:

G4 - 50% w/v in DMF

Key result

Parameter:

SI

Value:

13.06

Test group / Remarks:

25% v/v HCA in DMF

Cellular proliferation data / Observations:

CELLULAR PROLIFERATION DATA ; Proliferative responses in the draining lymph nodes were monitored by measuring the incorporation of 3H-methyl thymidine. These analyses revealed group mean DPM values of 307.00, 316.60, 328.80, and 531.00 for the vehicle control, 10%, 25%, and 50% (w/v)

DETAILS ON STIMULATION INDEX CALCULATION ; Stimulation Index (SI) values calculated, for groups treated with Reaction mass of N, N’-bis [2-(octadecanoylamino) ethyl] decanediamide and N, N’-bis [2-(hexadecanoylamino) ethyl] decanediamide, were found to be 1.03, 1.25 and 1.73 at the dose concentrations of 10%, 25% and 50% (w/v) in dimethylformamide, respectively, and 13.06 for the 25% v/v HCA treated positive control group

EC3 CALCULATION ; Ther was no EC3 calculation.

CLINICAL OBSERVATIONS: ; No clinical signs were observed in any mice from the vehicle control, positive control or any treated group at 10%, 25% and 50% (w/v)

BODY WEIGHTS; The mean body weight of positive control and Reaction mass of N, N’-bis [2-(octadecanoylamino) ethyl] decanediamide and N, N’-bis [2-(hexadecanoylamino) ethyl] decanediamide treated mice was comparable to that of the vehicle control group

Interpretation of results:

GHS criteria not met

Conclusions:

Based on results of this study, the classification for Reaction mass of N, N’-bis [2-(octadecanoylamino) ethyl] decanediamide and N, N’-bis [2-(hexadecanoylamino) ethyl] decanediamide is as follows: Globally Harmonized System of Classification and Labelling of Chemicals (GHS 2017) : Not Classified as a Skin Sensitiser

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Substance not classified as no sensitisation was recorded.