5-cyclohexadecen-1-one

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30 August - 13 October 1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The in vivo study (non LLNA) was conducted prior to the new approach on use of alternative methods to animal testing described in the Draft version (5) published by ECHA in June 2016 : Chapter R.7a: Endpoint specific guidance.
Indeed as recommended by the ECHA Guidance on Information Requirements and Chemical Safety Assessment publised version 4.1 (Chapter R.7a) published in October 2015, the assessment of skin sensitization is firstly based on the available human, animal and alternative data.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

not specified

Type of study:

open epicutaneous test

Justification for non-LLNA method:

As the In vivo non LLNA study was already available and reliable to assess the skin sensitization potential and determined the skin sensitization classification of VELVIONE, it has been used to fill the sensitization endpoint and no futher test were conducted.

Test material

Test material information

Constituent 1

Reference substance name:

(E)-cyclohexadec-5-enone

Cas Number:

35951-24-7

Molecular formula:

C16H28O

IUPAC Name:

(E)-cyclohexadec-5-enone

Constituent 2

Reference substance name:

(Z)-cyclohexadec-5-enone

Cas Number:

21944-95-6

Molecular formula:

C16H28O

IUPAC Name:

(Z)-cyclohexadec-5-enone

Specific details on test material used for the study:

Name (as stated in the report): Velvione
Batch: 9000319175

In vivo test system

Test animals

Species:

guinea pig

Strain:

other: Albino female, GOHI (SPF)

Sex:

female

Details on test animals and environmental conditions:

Conditions: Air conditioned with 15 -20 air changes per hour, temperature of 22 +/- 2°C, relative humidity of 55 +/- 10%, 12 hours artificial light and 12 hours of darkness
Accomodations: Individually housed in metallic/ steel boxes
Diet: Kliba 3418 ad libitium
Water: Community tap water from Basle ad libitium

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, open

Vehicle:

other: Ethanol

Concentration / amount:

Contraction: 30%, 10% and 5% in Ethanol
Amount: 100 microL/8 cm2

Day(s)/duration:

4 consecutive weeks

Challenge

Challenge 1

No.:

#1

Route:

epicutaneous, open

Vehicle:

other: Ethanol

Concentration / amount:

Concentrations: 1%, 0.5%, 0.1%, 0.05% and 0%
Amount: 25 microL/2cm2

Day(s)/duration:

four week after the beginning of the induction

Adequacy of challenge:

other: non-irritating concentrations

Challenge 2

No.:

#2

Route:

epicutaneous, open

Vehicle:

other: Ethanol

Concentration / amount:

Concentrations: 1%, 0.5%, 0.1% and 0%
Amount: 25 microL/2cm2

Day(s)/duration:

Two weeks later the 1st challenge

Adequacy of challenge:

other: non-irritating concentrations

No. of animals per dose:

1 dose per animal

Details on study design:

Induction:
During the induction phase of sensitization, Velvione was applied epicutaneously onto skin of the test animals 5 days a week for 4 consecutive weeks. Six animal per treatement group were treated on the right flank with the test article at the concentrations of 30%, 10% and 5% in ethanol, respectively. Treatement sites were left open between the subsequent applications. The control group (10 animals) was treated similarly biut with the vehicul only.

Challenge 1:
To assess the sensitization responses, 4 weeks beginning of the induction treatment a challenge application has been carried out. The animals (test and control) have been exposed on the left flank, by open epicutaneous way, to Velvione at the non-irritating concentrations of 1%, 0.5%, 0.1% and 0.05% in ethanol.

Challenge 2:
Two week later a second challenge was done similarly with the test article. The cutaneous reactions, such as erythema and oedema formation were evaluated daily at each individual treatment site during the induction period.
Challenge reactions were assessed at 24 and 48 hours after application.

Challenge controls:

Challenge 1 and 2: The animals (test and control) have been exposed on the left flank, by open epicutaneous way, to Velvione at the non-irritating concentrations of 1%, 0.5%, 0.1% and 0.05% in ethanol.

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

other: 3 Test groups (30%, 10% and 5% treated during the induction phase)

Dose level:

1%, 0.5%, 0.1%, 0.05% and 0.0%

No. with + reactions:

0

Total no. in group:

6

Remarks on result:

other: 1st reading: 24 hours after the 1st and 2nd challenge

Results 2

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

other: 3 test groups (30%, 10% and 5% treated during the induction phase)

Dose level:

1%, 0.5%, 0.1%, 0.05% and 0.0%

No. with + reactions:

0

Total no. in group:

6

Remarks on result:

other: 2nd reading: 48 hours after the 1st and 2nd challenge

Any other information on results incl. tables

Velvione did not induce any skin reactions as such in the test or control animals during the challenge phase of the experiment. The test articple when applied at the concentrations of 30%, 10% and 5% in ethanol induced slight to intense cutaneous responses of primary irritant nature during the induction phase of the study only.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the above experimental data, it is concluded that the topically applied Velvione when used under the conditions of this study (<= 30%) did not induce cutaneous sensitization in the guinea pigs.
Hence, VELVIONE does not met the criteria for skin sensitization classication according the CLP Regulation (EC) No. 1272/2008.

Executive summary:

VELVIONE was tested under the test conditions decribed below for evaluation of the skin sensitzation potential according to the OECD guideline 406.

During the induction phase of sensitization, Velvione was applied epicutaneously onto skin of the test animals 5 days a week for 4 consecutive weeks. Six animal per treatement group were treated on the right flank with the test article at the concentrations of 30%, 10% and 5% in ethanol, respectively. Treatement sites were left open between the subsequent applications. The control group (10 animals) was treated similarly biut with the vehicul only.

To assess the sensitization responses, 4 weeks beginning of the induction treatment a challenge application has been carried out. The animals (test and control) have been exposed on the left flank, by open epicutaneous way, to Velvione at the non-irritating concentrations of 1%, 0.5%, 0.1% and 0.05% in ethanol.

Two week later a second challenge was done similarly with the test article. The cutaneous reactions, such as erythema and oedema formation were evaluated daily at each individual treatment site during the induction period. Challenge reactions were assessed at 24 and 48 hours after application.

Velvione did not induce any skin reactions as such in the test or control animals during the challenge phase of the experiment. The test articple when applied at the concentrations of 30%, 10% and 5% in ethanol induced slight to intense cutaneous responses of primary irritant nature during the induction phase of the study only.

It is concluded that the topically applied Velvione when used under the conditions of this study (<= 30%) did not induce cutaneous sensitization in the guinea pigs.

Hence, VELVIONE does not met the criteria for skin sensitization classication according the CLP Regulation (EC) No. 1272/2008.