4,4'-bis(dimethylamino)-4''-(methylamino)trityl alcohol

Endpoint summary

Description of key information

The skin sensitization potential of test chemical was assessed in various experimental studies conducted on human subjects. Based on the available data for the test chemical and supporting studies, it can be concluded that the test chemical is unable to cause skin sensitization and thus can be considered as not sensitizing. Comparing the above annotations with the criteria of CLP regulation, it can be classified under the category “not classified”.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

experimental data of read across substances

Justification for type of information:

Data for the target chemical is summarized based on the structurally similar read across chemicals

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

WoE report is based on 3 skin sensitization studies as- WoE-2, WoE-3 and WoE-4.
Skin sensitization of test chemical was determined by performing tests on humans and rabbits.

GLP compliance:

not specified

Type of study:

other: 1.a modified Buehler and Klecak method

Species:

guinea pig

Strain:

other: 3.Hartley

Sex:

female

Details on test animals and environmental conditions:

1.Each animal received 0.1 ml of the dye test material over a 1.8-cm circular area.
3.TEST ANIMALS
- Source: No data
- Age at study initiation: No data
- Weight at study initiation: 370 - 420 g
- Fasting period before study: No data
- Housing: The animals were housed singly in stainless steel wire-mesh cages
- Diet (e.g. ad libitum): A standard guinea pig diet, ad libitum.
- Water (e.g. ad libitum): Water, ad libitum
- Acclimation period: no data available

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 23±2 ◦C
- Humidity (%): 55±5%
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): 12 h daily

IN-LIFE DATES: No data

Route:

other: 1.epicutaneous

Vehicle:

propylene glycol

Concentration / amount:

10%

Day(s)/duration:

3 weeks

Adequacy of induction:

not specified

Route:

other: 2. epicutaneous,open

Vehicle:

propylene glycol

Concentration / amount:

10%

Route:

other: 3.intradermal

Vehicle:

other: acetone

Concentration / amount:

Aliquots of 0.1 ml each of a water-in-oil type emulsion (distilled water: FCA =1:1) were injected intradermally into the four corners of a previously shaved shoulder region (2 cm×4 cm). At the injection sites, scratches in the shape of a grid were made with the needle used for injection.

Day(s)/duration:

not specified

Adequacy of induction:

not specified

Route:

other: 3.epicutaneous, occlusive

Vehicle:

other: acetone

Concentration / amount:

0.1 ml of 1, 0.1 and 0.01%

Day(s)/duration:

24 hours

Adequacy of induction:

not specified

No.:

#1

Route:

other: 1. epicutaneous

Vehicle:

propylene glycol

Concentration / amount:

10%,5% and 2.5%

Day(s)/duration:

48 hours

Adequacy of challenge:

not specified

No.:

#1

Route:

other: 2.epicutaneous,open

Vehicle:

propylene glycol

Concentration / amount:

10%,5% and 2.5%

No.:

#1

Route:

other: 3. epicutaneous, occlusive

Vehicle:

other: acetone

Concentration / amount:

0.1 ml of 1, 0.1 and 0.01%

Day(s)/duration:

48 hours

Adequacy of challenge:

not specified

No. of animals per dose:

1.10
2.10 animals
3.20 (10 animals/ group)

Details on study design:

1.MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 9
- Exposure period: 24 hour
- Test groups: 10
- Control group: no data
- Site: shaved left flanks of ten albino guinea pigs over a 1.8-cm circular area.
- Frequency of applications: three times weekly (Monday, Wednesday Friday) for three consecutive weeks.
- Duration: 3 weeks
- Concentrations:10%

B. CHALLENGE EXPOSURE
- No. of exposures:1
- Day(s) of challenge: Two week rest period
- Exposure period: 24 hours
- Test groups: 10
- Control group: no data
- Site: shaved left flanks of ten albino guinea pigs
- Concentrations: 100%,50%, and 25%
- Evaluation (hr after challenge): 24 hour and 48 hours

2.Details on study design
MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 9
- Exposure period:48 hour
- Test groups: 10
- Control group: no data
- Site: the left flanks of ten albino guinea pigs were shavedand the test material applied three timesweekly( Monday,Wednesday,Friday)for three consecutiv weeeks. Each animal received 0.1 ml of the dye test material over a 1.8-cm circular area.
- Frequency of applications: three times weekly (Monday, Wednesday Friday) for three consecutive weeks.
- Duration: 3 weeks
- Concentrations:10%

B. CHALLENGE EXPOSURE
- No. of exposures:1
- Day(s) of challenge: Two week rest period
- Exposure period: 24 hour
- Test groups: 10
- Control group: No data available.
- Site: right flank of each guinea pig was shaved and test material applied on it.
- Concentrations: 10.0%, 5.0%, and 2.5%
- Evaluation (hr after challenge): 24 hour and 48 hours post-application

Other – The test sites were graded for erythema and edema 24 and 48 hours post-application using a four-point ordinal scale (0 = no reaction, 1 -- slight reaction, 2 = moderate reaction, 3 = severe reaction. A positive reaction was defined as an erythema/edema value during the challenge phase of at least one skin grade higher than during the last induction phase.

3.MAIN STUDY
A. INDUCTION EXPOSURE: intradermal
Aliquots of 0.1 ml each of a water-in-oil type emulsion (distilled water: FCA =1:1) were injected intradermally into the four corners of a previously shaved shoulder region (2 cm×4 cm). At the injection sites, scratches in the shape of a grid were made with the needle used for injection.

B. INDUCTION EXPOSURE: dermal
- No. of exposures: 2
- Exposure period: 24 hours
- Test groups: 10
- Control group: 10
- Site: no data
- Frequency of applications: no data
- Duration: 48 hours
- Concentrations: 0.1 ml of 1, 0.1 and 0.01%


B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: after 2 weeks
- Exposure period: 24 hours
- Test groups: 10
- Control group: 10
- Site: shaved skin of the back
- Concentrations: 0.1 ml of 1, 0.1 and 0.01%
- Evaluation (hr after challenge): after 24 days
OTHER: during topical induction, a closed patch with 0.1 ml of test preparation was applied to the sites for 24 h. Abrasions and sample applications were repeated on the following 2 days. One week after the initial sensitization, 10% sodium lauryl sulfate in petrolatum was applied to the intradermal injection sites. On the next day, a closed patch of the test preparation was applied at the same sites for 48 h.

Challenge controls:

3.yes, concurrent vehicle.

Positive control substance(s):

yes

Remarks:

1. 0.5% DNCB ,2.DNCB (2,4-dinitrochlorobenze)

Positive control results:

1.The positive DNCB (2, 4-dinitrochlorobenze) control at the 0.5% induction /challenge concentration elicited positive response in all animals tested.
2.The positive DNCB (2,4-dinitrochlorobenze) control at the 0.5% induction /challenge concentration elicited positive response in all animals tested.

Reading:

other: 1. 1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

10%,5% and 2.5 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

not sensitizing

Remarks on result:

no indication of skin sensitisation

Reading:

other: 1. 2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

10%,5% and 2.5%

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

not sensitizing

Remarks on result:

no indication of skin sensitisation

Reading:

other: 2.challenge

Hours after challenge:

24

Group:

test chemical

Dose level:

10%,5% and 2.5 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no sensitization reaction observed

Remarks on result:

no indication of skin sensitisation

Reading:

other: 2.challenge

Hours after challenge:

48

Group:

test chemical

Dose level:

10%,5% and 2.5%

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no sensitization reaction observed

Remarks on result:

no indication of skin sensitisation

Reading:

other: 3. 1st reading

Hours after challenge:

48

Group:

test chemical

Dose level:

0.01-1%

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no erythema or edema

Remarks on result:

no indication of skin sensitisation

Reading:

other: 3. 1st reading

Hours after challenge:

48

Group:

other: control group

Dose level:

0.01-1%

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no skin reactions were observed

Remarks on result:

no indication of skin sensitisation

1.All test sites were graded for erythema and edema 24 and 48 hours post-application using a four-point ordinal scale

 0 = no reaction,

 1 = slight reaction,

2 = moderate reaction and

3 = severe reaction.

A positive reaction was defined as an erythema/edemavalue during the challenge phase of at least one skin grade higher than during the last induction phase.

2.No indication of skin sensitization observed.

3.Contact hypersensitivity of D&C Green No. 6

Challenge Substance	Concentration (%)	Sensitized Group		Control Group
D&C Green No. 6 (purified)		FR	MR	FR	MR
	1	0/10	0	0/10	0
	0.1	0/10	0	0/10	0
	0.01	0/10	0	0/10	0

Induction: 1% D&C Green No. 6 (commercial grade). Solvent: acetone, FR: fractional response, MR: mean response.

Interpretation of results:

other: not sensitising

Conclusions:

The test chemical was considered to be not sensitizing to the skin on the basis of summarized studies.

Executive summary:

Data available for the structurally and functionally similar read across chemicals has been reviewed to determine the skin sensitization potential of the test chemical. The studies are as mentioned below:

Skin sensitization test for test chemical was conducted inguinea pig using modified Buehler and Klecak method for open Epicutaneous testing. For the induction phase, the left flanks of 10 albino guinea pigs were shaved and the dye test material applied three times weekly (Monday, Wednesday Friday) for three consecutive weeks. Each animal received 0.1 ml of the dye test material over a 1.8-cm circular area. Following the induction period, the guinea pigs entered the challenge phase. The challenge phase began after a two-week rest period when the right flank of each guinea pig was shaved and exposed to three different dye test material concentration (10.0%,5.0%, and 2.5% of the induction concentration). Twenty-four hours after the last induction and challenge application, the animals were depilated to clearly observe dermal reactions.The test sites were graded for erythema and edema 24 and 48 hours post-application using a four-point ordinal scale (0 = no reaction, 1 -- slight reaction, 2 = moderate reaction, 3 = severe reaction. A positive reaction was defined as an erythema/edema value during the challenge phase of at least one skin grade higher than during the last induction phase. No erythema/edema was observed after 24 and 48 hours post-application. Hence the test chemical was considered as not sensitizing to the guinea pigs skin.

In another study,Skin sensitization test for test chemical was conducted in guinea pig using modified Buehler and Klecak method for open Epicutaneous testing.For the induction phase, the left flanks of 10 albino guinea pigs were shaved and the dye test material applied three times weekly (Monday, Wednesday Friday) for three consecutive weeks. Each animal received 0.1 ml of the dye test material over a 1.8-cm circular area. After a rest period of two weeks. In challenge phase the right flank of each guinea pig was shaved and exposed to three different concentration 10.0%, 5.0%, and 2.5%.Twenty-four hours after the last induction and challenge application, the animals were depilated to clearly observe dermal reactions. No erythema/edema was observed after application of test material .The test result was observed to be negative for the test substance. Therefore test chemical was considered to be not sensitizing to the skin of guinea pig using modified Buehler and Klecak method for open Epicutaneous testing .

The above results were further supported by a modified guinea pig testing technique, the adjuvant and patch test was conducted on Hartley strain female albino guinea pigs to evaluate the contact hypersensitivity of test chemical. In intradermal induction,aliquots of 0.1 ml each of a water-in-oil type emulsion (distilled water: FCA =1:1) were injected intradermally into the four corners of a previously shaved shoulder region (2 cm×4 cm). At the injection sites, scratches in the shape of agrid were made with the needle used for injection. During topical induction, a closed patch with 0.1 ml of purified test preparation (1, 0.1 and 0.01%) was applied to the sites for 24 h. Abrasions and sample applications were repeated on the following 2 days. One week after the initial sensitization, 10% sodium lauryl sulfate in petrolatum was applied to the intradermal injection sites. On the next day, a closed patch of the test preparation was applied at the same sites for 48 h.After a rest period of 2 weeks, animals were challenged with the same purified test preparations (1, 0.1 and 0.01%) onto the shaved skin of the back.The skin reactions, fractional response (FR) and mean response (MR), were scored at 1, 24 and 48 h after the washing.The fractional response (FR) and mean response (MR) was observed to be 0.0 at each tested concentration. Since no response was detected topurified test preparation (1, 0.1 and 0.01%) in test and control group , the test chemical was considered to be not sensitizing to the skin of Hartley strain female albino guinea pigs.

Based on the above summarized studies for target chemical and its structurally and functionally similar read across substances,it can be concluded that the test chemical is unable to cause skin sensitization and considered as non-skin sensitizer. Comparing the above annotations with the criteria of CLP regulation, it can be classified under the category “Not Classified”.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Data available for the structurally and functionally similar read across chemicals has been reviewed to determine the skin sensitization potential of the test chemical. The studies are as mentioned below:

Skin sensitization test for test chemical was conducted inguinea pig using modified Buehler and Klecak method for open Epicutaneous testing. For the induction phase, the left flanks of 10 albino guinea pigs were shaved and the dye test material applied three times weekly (Monday, Wednesday Friday) for three consecutive weeks. Each animal received 0.1 ml of the dye test material over a 1.8-cm circular area. Following the induction period, the guinea pigs entered the challenge phase. The challenge phase began after a two-week rest period when the right flank of each guinea pig was shaved and exposed to three different dye test material concentration (10.0%,5.0%, and 2.5% of the induction concentration). Twenty-four hours after the last induction and challenge application, the animals were depilated to clearly observe dermal reactions.The test sites were graded for erythema and edema 24 and 48 hours post-application using a four-point ordinal scale (0 = no reaction, 1 -- slight reaction, 2 = moderate reaction, 3 = severe reaction. A positive reaction was defined as an erythema/edema value during the challenge phase of at least one skin grade higher than during the last induction phase. No erythema/edema was observed after 24 and 48 hours post-application. Hence the test chemical was considered as not sensitizing to the guinea pigs skin.

In another study,Skin sensitization test for test chemical was conducted in guinea pig using modified Buehler and Klecak method for open Epicutaneous testing.For the induction phase, the left flanks of 10 albino guinea pigs were shaved and the dye test material applied three times weekly (Monday, Wednesday Friday) for three consecutive weeks. Each animal received 0.1 ml of the dye test material over a 1.8-cm circular area. After a rest period of two weeks. In challenge phase the right flank of each guinea pig was shaved and exposed to three different concentration 10.0%, 5.0%, and 2.5%.Twenty-four hours after the last induction and challenge application, the animals were depilated to clearly observe dermal reactions. No erythema/edema was observed after application of test material .The test result was observed to be negative for the test substance. Therefore test chemical was considered to be not sensitizing to the skin of guinea pig using modified Buehler and Klecak method for open Epicutaneous testing .

The above results were further supported by a modified guinea pig testing technique, the adjuvant and patch test was conducted on Hartley strain female albino guinea pigs to evaluate the contact hypersensitivity of test chemical. In intradermal induction,aliquots of 0.1 ml each of a water-in-oil type emulsion (distilled water: FCA =1:1) were injected intradermally into the four corners of a previously shaved shoulder region (2 cm×4 cm). At the injection sites, scratches in the shape of agrid were made with the needle used for injection. During topical induction, a closed patch with 0.1 ml of purified test preparation (1, 0.1 and 0.01%) was applied to the sites for 24 h. Abrasions and sample applications were repeated on the following 2 days. One week after the initial sensitization, 10% sodium lauryl sulfate in petrolatum was applied to the intradermal injection sites. On the next day, a closed patch of the test preparation was applied at the same sites for 48 h.After a rest period of 2 weeks, animals were challenged with the same purified test preparations (1, 0.1 and 0.01%) onto the shaved skin of the back.The skin reactions, fractional response (FR) and mean response (MR), were scored at 1, 24 and 48 h after the washing.The fractional response (FR) and mean response (MR) was observed to be 0.0 at each tested concentration. Since no response was detected topurified test preparation (1, 0.1 and 0.01%) in test and control group , the test chemical was considered to be not sensitizing to the skin of Hartley strain female albino guinea pigs.

Based on the above summarized studies for target chemical and its structurally and functionally similar read across substances,it can be concluded that the test chemical is unable to cause skin sensitization and considered as non-skin sensitizer. Comparing the above annotations with the criteria of CLP regulation, it can be classified under the category “Not Classified”.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The skin sensitization potential of test substance and its structurally and functionally similar read across substances were observed in various studies. From the results obtained from these studies it is concluded that the chemical is not likely to cause skin sensitization and hence can be classified as non-skin sensitizer.