Disodium 3,3'-[[6-[bis(2-hydroxyethyl)amino]-1,3,5-triazine-2,4-diyl]bis[imino(3-methoxy-4,1-phenylene)azo]]bis[benzenesulphonate]

Endpoint summary

Description of key information

Non-skin sensitizing

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:

key study

Study period:

From December 20, 1988 to January 27, 1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Justification for type of information:

The read across approach has been detailed in the report attached to the IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Version / remarks:

adopted on May 12, 1981

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

Old experiment

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River Wiga, Sulzfeld / West Germany.
- Age at study initiation: approximately 11 weeks.
- Weight: 318 - 455 gram, at acclimatisation.
- Housing: group housing of 2 animals per half of metal cages with wire-mesh floors.
- Diet: free access to standard guinea pig diet, including ascorbic acid (1600 mg/kg); LC 23-B, pellet diameter 4mm. In addition, once a week hay was provided.
- Water: free access to tap-water, diluted with decalcified water.
- Acclimation period: at least five days under test conditions after physical examination.

ENVIRONMENTAL CONDITIONS
- Temperature: 21 ± 3 °C
- Humidity: 30 - 70 %
- Air changes: air-conditioned with 7.5-15 air changes per hour.
- Photoperiod: 12 hours artificial fluorescent light/12 hours dark.

Route:

intradermal

Vehicle:

water

Remarks:

aqua dest

Concentration / amount:

5 %

Route:

epicutaneous, occlusive

Vehicle:

water

Remarks:

milli-RO water

Concentration / amount:

25 %

Day(s)/duration:

48 hours

Route:

epicutaneous, occlusive

Vehicle:

water

Remarks:

milli-RO water

Concentration / amount:

2, 5, 10 %

Day(s)/duration:

24 hours

No. of animals per dose:

10 females for the control group and 20 females for the experimental group
5 animals were used for the primary irritation test, one week before the main study.

Details on study design:

RANGE FINDING TESTS
The objective of this investigation was to identify irritant test article concentrations suitable for the induction phase of the main study. In addition, a suitable non-irritant concentration of the test article, by the topical route of administration, was identified for the challenge application.
Any systemic toxic effects may also be detected in the primary irritation experiments.

Intradermal injections
Four intradermal injections (0.1 ml/site) were made into the clipped shoulder region of one guinea pig at a concentration of 5 % (w/w) of the test article in milli-RO water. The resulting dermal reactions were assessed 24 hours later.

Epidermai appiications
The intracutaneousiy injected animal was also treated epicutaneousiy at the shaved left fiank with 0.5 mi of a 50 % concentration of the test articie in milli-RO water using a Metaliine patch mounted on Micropore and heid in place with Coban for 24 hours. The treated skin was assessed for erythema 24 and 48 hours after removai of the dressings on a numericai basis.
Four animals were shaved on the left fiank and exposed for 24 hours to 50 %, 25 %, 10 % and 5 % (w/w) test articie concentrations in milli-RO water (0.05 ml/concentration), occlusively administered by means of Square chambers mounted on Micropore. The bandage was fixed in place by means of Cuban. The reaction sites were assessed for erythema on a numericai basis, 24 and 48 hours after removai of the dressings.

MAIN STUDY
A. INDUCTION EXPOSURE
Intradermal application
On day 1 an area of the dorsal skin from the scapular region (approximately 6 x 8 cm) was clipped free of hair. Three pairs of intradermal injections (0.1 ml/site) were made at the border of a 4 x 6 cm area in the clipped region as follows:
A) The test article dissolved to 5 % (wlw) with aqua dest (pyrogene free)
B) Freunds’ Complete Adjuvant, 50:50 with distilled water for injection
C) The test article, at twice the concentration used in (A), emulsified in a 50:50 mixture of Freunds’ Complete Adjuvant.

Epidermal applications
Seven days after the intradermal injections, the scapular area (approximately 6 x 8 cm) was again clipped and shaved free of hair. A 2 x 4 cm patch of Metalline mounted on Micropore was treated with 0.5 ml of the test article (25 % (wlw) in milli-RO water) and placed over the injection sites of the test animals. The Micropore tape was firmly secured, wrapped around the trunk of the animal and secured with Cuban. The dressings were left in place for approximately 48 hours.
The epidermal application procedure described ensured intensive contact of the test article even if it is insoluble in the vehicle used.
The guinea pigs of the control group were treated as described above by the intradermal and epidermal inductions with the omission of test article.
Reaction sites were assessed for erythema immediately after removal of the dressings, using the numerical grading system.

B. CHALLENGE EXPOSURE
The test and control guinea pigs were challenged two weeks after the epidermal induction application.
Hair was clipped and shaved from a 5 x 5 cm area on the left flank of each guinea-pig. The following series of 3 test article concentrations and the vehicle were applied using Square chambers, attached to Micropore tape:
a = 10 % in milli-RO water
b = 5 % in milli-RO water
c = 2 % in milli-RO water
d = milli-RO water
Of each concentration and the vehicle, 0.05 ml was brought on the Square chamber. The patch was placed to the shaved area, the Micropore firmly secured, wound around the trunk of the animals and held in place by Coban.
The dressings and residual test article were removed after approximately 24 hours.
The sites were assessed for redness and swelling 24 and 48 hours after removal of the dressings, using the numerical grading system (modified from Kligman A.M., J. Invest. Dermatol. 47, 1966).
The test sites were shaved with an electric razor after the first reading.

Positive control substance(s):

yes

Remarks:

A positive control experiment is carried out once a year as a sensitivity check of the test system. The most recent test was carried out in December 1988

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

0, 2, 5, 10 %

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

No symptoms of systemic toxicity were observed.

Remarks on result:

no indication of skin sensitisation

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

0 % milli-RO water

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

No symptoms of systemic toxicity were observed.

Remarks on result:

no indication of skin sensitisation

Reading:

other: challenge

Group:

positive control

Dose level:

0.5 %

No. with + reactions:

18

Total no. in group:

20

Clinical observations:

-

Remarks on result:

positive indication of skin sensitisation

RANGE FINDING TESTS

No signs of systemic toxicity were observed during the primary irritation experiments.

INDUCTION

All experimental animals showed skin irritation after the 48 hours occluded epicutaneous induction exposure.

CHALLENGE

Control group: no positive skin reactions were evident after the challenge exposure.

Experimental group: none of the animals showed a positive reaction in response to any of the challenge concentrations.

TOXICITY SYMPTOMS / MORTALITY

No symptoms of systemic toxicity were observed in the animals during the study. No mortality occurred during the study.

BODY WEIGHTS

The average body weight gain of experimental and control animals was similar.

Interpretation of results:

other: not classified, according to the CLP Regulation (EC) No 1272/2008

Conclusions:

Non-sensitizing

Executive summary:

The skin sesitization potential of the test substance was assayed following the method and testing procedures outlined into the OECD guideline 406, Guinea Pig Maximization Test. 35 female guinea pig were used: 10 females for the control group and 20 females for the experimental group; the remaining 5 animals were used for the primary irritation test, one week before the main study.

In accordance with Magnusson and Kilgman (1969) and based on the findings in the primary irritation experiments, the following concentrations were selected for the induction and challenge phase: intracutaneous induction at 5 % (w/w) in aqua dest and epicutaneous induction at 25 % (w/w) in milli-RO water; challenge at 0, 2, 5, and 10 % (w/w) in milli-RO water.

Under the experiment conditions, test item sensitization rate recorded was of 0 per cent, after intracutaneous and epicutaneous application to the guinea pig. No symptoms of systemic toxicity were observed in the animals during the study. No mortality occurred during the study. The average body weight gain of experimental and control animals was similar.

According to the results, the substamce is considered to have weak sensitising properties applying the rating of aliergenicity described by Kilgman A.M. (1966).

Conclusion

Non-sensitizing

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

There is no information about the skin sensitization potential of Direct Yellow 142, thus the available data on structural analogous Similar Substance 01 has been taken into account. The read across approach can be considered as reliable and adequate for the purpose; details and explanations are detailed in the report attached to the IUCLID section 13.

The skin sensitization potential of the Similar Substance 01 was assayed following the method and testing procedures outlined into the OECD guideline 406, Guinea Pig Maximization Test. In accordance with Magnusson and Kilgman (1969) and based on the findings in the primary irritation experiments, the following concentrations were selected for the induction and challenge phase: intracutaneous induction at 5 % (w/w) in aqua dest and epicutaneous induction at 25 % (w/w) in milli-RO water; challenge at 0, 2, 5, and 10 % (w/w) in milli-RO water. Under the experiment conditions, test item sensitization rate recorded was of 0 per cent, after intracutaneous and epicutaneous application to the guinea pig. No symptoms of systemic toxicity were observed in the animals during the study. No mortality occurred during the study. The average body weight gain of experimental and control animals was similar.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

According to the CLP Regulation (EC) No 1272/2008, 3.4 Respiratory or skin sensitisation section, skin sensitizer means a substance that will lead to an allergic response following skin contact.

Based on the Guinea Pig Maximisation Test (GPMT) results, a substance in considered a skin sensitizer when: equal or more than 30 % to 60 % responding at intradermal induction dose > 0.1 % to ≤ 1 %; or equal or more than 30 % responding at intradermal induction dose higher than 1 %.

In the GPMT a response lower than 30 % was recorded, responding to intracutaneous inductionn dose of 5 %.

In conclusion, Direct Yellow 142 does not meet the criteria to be classified as skin sensitizer, according to the CLP Regulation (EC) No 1272/2008.