Tetramethyl 2,2'-[1,4-phenylenebis[imino(1-acetyl-2-oxoethane-1,2-diyl)azo]]bisterephthalate

Endpoint summary

Description of key information

Not sensitising to skin as assessed in a guinea pig maximization assays (OECD 406)

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

yes (incl. QA statement)

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

A valid guinea pig maximization study with the test substance is available.

Specific details on test material used for the study:

- Lot/batch No.: 201P69495
- Expiration date of the lot/batch: 22-MAY-2005
- Stability under test conditions: stable
- Storage condition of test material: room temperature

Species:

guinea pig

Strain:

Himalayan

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: RCC Ltd, Biotechnology & Animal Breeding Division, Wölferstrasse 4, CH-4414 Fullinsdorf
- Age at study initiation: 4 - 6 weeks at delivery
- Weight at study initiation: 300 - 359 g
- Housing: Individually
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: one week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3 (air conditioned room)
- Humidity (%): 30 - 70
- Air changes (per hr): 10 - 15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 2001-07-03 To: 2001-08-03

Route:

intradermal and epicutaneous

Vehicle:

polyethylene glycol

Concentration / amount:

10% (intradermal)
30% (epicutaneous)

Route:

epicutaneous, occlusive

Vehicle:

polyethylene glycol

Concentration / amount:

10% (intradermal)
30% (epicutaneous)

No. of animals per dose:

10 test group
5 control group

Details on study design:

The intradermal induction of sensitization in the test group was performed in the nuchal region with a 10 % dilution of the test item in PEG 300 and in an emulsion of Freund's Complete Adjuvant (FCA) / physiological saline. The epidermal induction of sensitization was conducted for 48 hours under occlusion with the test item at 30% in PEG 300 one week after the intradermal induction. The animals of the control group were intradermally induced
with PEG 300 and FCA/physiological saline and epidermally induced with PEG 300 under occlusion.
Two weeks after epidermal induction the control and test animals were challenged by epidermal application of the test item at 10% in PEG 300 and PEG 300 alone under occlusive dressing.

Challenge controls:

CONTROL GROUP
TONER YELLOW 3GP, 10% in PEG 300 (left flank)
PEG 300 only (right flank)

TEST GROUP
TONER YELLOW 3GP, 10% in PEG 300 (left flank)
PEG 300 only (right flank)

Positive control substance(s):

yes

Remarks:

2-MERCAPTOBENZOTHIAZOLE

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

10%

No. with + reactions:

0

Total no. in group:

9

Clinical observations:

none

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

10%

No. with + reactions:

0

Total no. in group:

9

Clinical observations:

none

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

10%

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

none

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

10%

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

none

Challenge with vehicle only caused no skin reactions in the control group and test group, respectively.

CONTROL GROUP

No skin reactions were observed in the animals when treated with either PEG 300 only or when treated with the test item at 10% in PEG 300. Yellow discoloration produced by the test item was noted directly after removal of the patch.

TEST GROUP

No skin reactions were observed in the surviving animals when treated with either PEG 300 only or when treated with the test item at 10% in PEG 300. Yellow discoloration produced by the test item was noted directly after removal of the patch. To remove the discoloration all animals were depilated 3 hours prior to challenge reading.

The body weight of the animals was within the range commonly recorded for animals of this strain and age. No clinical signs were observed. To remove the discoloration all animals were depilated 3 hours prior to challenge reading.

One animal died during the study. No cause of death could be identified and no skin reactions were observed. The death is considered to be incidental.

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

A guinea pig maximisation assay according to OECD TG 406 has been performed with the test substance (Clariant, 2001). The maximization test was performed in 15 (10 test and 5 control) female albino guinea pigs. The intradermal induction of sensitisation in the test group was performed in the nuchal region with a 10% dilution of the test item in PEG 300 and in an emulsion of Freund's Complete Adjuvant (FCA) I physiological saline. The epidermal induction of sensitisation was conducted for 48 hours under occlusion with the test item at 30% in PEG 300 one week after the intradermal induction. The animals of the control group were intradermally induced with PEG 300 and FCA/physiological saline and epidermally induced with PEG 300 under occlusion. Two weeks after epidermal induction the control and test animals were challenged by epidermal application of the test item at 10 % in PEG 300 and PEG 300 alone under occlusive dressing. Cutaneous reactions were evaluated at 24 and 48 hours after removal of the dressing. No toxic symptoms were evident in the guinea pigs of the control or test group. None of the control and test animals showed skin reactions after the challenge treatment at 10 % (w/w) in PEG 300.

Under the conditions of this test, the test substance is not considered to be sensitising to the skin.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Classification, Labelling, and Packaging Regulation (EC) No 1272/2008
The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. Based on available data on skin sensitisation, the test item is not classified according to Regulation (EC) No 1272/2008 (CLP).