1-phenylazo-2-naphthol

Endpoint summary

Description of key information

A 51-year-old man had been working in dye factory for 25 years and had noticed itching and pigmentation on the extremities for the past 5 years. On examination there were erythematous lesions, lichenification and pigmentation, diffusely and symmetrically over the dorsa of the hands, feet and legs. Patch test was performed having concentration of Sudan I is 1%. They were applied on the back for 48 hours, and the test read 1h and 24 h after removal according to the ICDRG Classification. Positive reaction was observed for to 1-phenylazo-2-naphthol (Sudan I).Therefore 1-phenylazo-2-naphthol (Sudan I) was considered to be a skin sensitizer and can be classiffied as sensitizer1 according to GHS criteria.

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Justification for type of information:

Data is from peer reviewed journal

Qualifier:

no guideline available

Principles of method if other than guideline:

To evaluate the skin sensitizing potential of 1-phenylazo-2-naphthol (Sudan I) in human by patch test.

GLP compliance:

not specified

Type of study:

patch test

Justification for non-LLNA method:

not specified

Specific details on test material used for the study:

Details on test material
Name of test material (as cited in study report): Sudan I
Molecular formula: C16H12N2O
Molecular weight: 248.284 g/mol
Physical State: Solid
Substance type: Organic

Species:

other: Human

Strain:

other:

Remarks:

Not applicable

Sex:

male

Details on test animals and environmental conditions:

Details on test animal
TEST ANIMALS
- Source: No data available
- Age at study initiation: 51 years old
- Weight at study initiation: No data available
- Housing: No data available
- Diet (e.g. ad libitum): No data available
- Water (e.g. ad libitum): No data available
- Acclimation period: No data available

ENVIRONMENTAL CONDITIONS
- Temperature (°C): No data available
- Humidity (%): No data available
- Air changes (per hr): No data available
- Photoperiod (hrs dark / hrs light): No data available

IN-LIFE DATES: From: To: No data available

Route:

other: not specified

Vehicle:

unchanged (no vehicle)

Concentration / amount:

1%

Day(s)/duration:

48 hour

No. of animals per dose:

1 human male

Details on study design:

Details on study design
RANGE FINDING TESTS:

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 1
- Exposure period: 48 hours
- Test groups: yes
- Control group: No data available
- Site: Back
- Frequency of applications: No data available
- Duration: 48 hour
- Concentrations: 1 %

OTHER:
- Evaluation (hr after induction exposure): 1hour and at 24 hour after removal of patch

Positive control substance(s):

not specified

Key result

Reading:

other: both 1and 2nd reading

Hours after challenge:

24

Group:

test chemical

Dose level:

1%

No. with + reactions:

2

Clinical observations:

Test area became pigmented.

Remarks on result:

positive indication of skin sensitisation

The test result was read according to ICDRG classification.

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

The substance 1-phenylazo-2-naphthol (Sudan I) was observed for its sensitizing potential in human. Sudan I was considered to be sensitizing in human male by patch test.

Executive summary:

A 51-year-old man had been working in dye factory for 25 years and had noticed itching and pigmentation on the extremities for the past 5 years. On examination there were erythematous lesions, lichenification and pigmentation, diffusely and symmetrically over the dorsa of the hands, feet and legs. Patch test was performed having concentration of Sudan I is 1%. They were applied on the back for 48 hours, and the test read 1h and 24 h after removal according to the ICDRG Classification. Positive reaction was observed for to 1-phenylazo-2-naphthol (Sudan I).Therefore 1-phenylazo-2-naphthol (Sudan I) was considered to be a skin sensitizer and can be classiffied as sensitizer1 according to GHS criteria.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

Skin sensitization

Various studies for target (,1-phenylazo-2-naphthol CAS No.-842-07-9) were summarized as follows:

A 51-year-old man had been working in dye factory for 25 years and had noticed itching and pigmentation on the extremities for the past 5 years. On examination there were erythematous lesions, lichenification and pigmentation, diffusely and symmetrically over the dorsa of the hands, feet and legs. Patch test was performed having concentration of Sudan I is 1%. They were applied on the back for 48 hours, and the test read 1h and 24 h after removal according to the ICDRG Classification. Positive reaction was observed for to 1-phenylazo-2-naphthol (Sudan I).Therefore 1-phenylazo-2-naphthol (Sudan I) was considered to be a skin sensitizer and can be classiffied as sensitizer1 according to GHS criteria.

An area of the back of tortoise shell guinea pigs (weight 250-300 g) was shaved with electric clippers and then with an electric razor. As sensitization procedure, the 24 hour closed patch testing 0.3% 1-phenylazo-2-naphthol in ethanol was performed in 10 animals every third day for 2 weeks. An untreated group of 5 animals was used as control. Eleven days after the last patch test, challenge procedure were performed daily for 1-3 days by applying 0.01ml of ethanol solution containing 0.1 % 1-phenylazo-2-naphthol to 3 untreated area on the back of the guinea pigs. The reaction were evaluated over a period of 43 days. The test result was positive. Allergic reaction and pigmentation was observed.Therefore 1-phenylazo-2-naphthol(CAS no-842-07-9) was considered to be sensitizing in tortoise shell guinea pigs.

Patch test was performed to five female by applying 1% concentration in petrolatum on the back of five female. The exposure time was 2 days. Reading were done 1h and 24 h after the patches were removed. 1-phenylazo-2-naphthol was found to be strong allergen in all cases. It shows erythema with edema, papule and vesicle in 1st, 4thand 5thcase and erythema with edema in 2ndand 3rdcase.Therefore 1-phenylazo-2-naphthol(CAS no-842-07-9) was considered to be skin sensitizer in human.

Skin sensitizationn test was conducted in guniea pig by fallowing way.

Part 1:A series of four sacral intradermal injection was given one each week over a one week period witch considered of 0.1ml of a 1% solution (vol/vol) of oil orange 15 % AI in water. Following a two week rest period, the test animals were challenged for sensitization by applying, and lightly rubbing in, one drop ( ̴0.05 ml) of H-8575 as supplied and a 50 % solution (vol/vol) of H-8575 in water on the shaved intact shoulder skin. It produced strong erythema with edema in 7/10 test and pig challenge. This material is strong sensitizer. A further test is determine what ingredient in the formulation is responsible for the sensitization follows.

 Part 2(Re-challenge test):-When guinea pig sensitizes to oil orange dye 15%AI were challenged with a 50% solution of oil orange dye 15 % AI 7/10 guinea pig has a sensitization response. When challenged with a 7.5 % solution of recrystallized oil orange in propylene glycol, 9/10 guinea pig has a sensitization response. When challenged with a 50 % solution of the mix of adjuvants, there was no evidence of sensitization in any of the guinea pigs. It can therefore concluded that the sensitization the oil orange dye 15 % AI was result of the oil orange and not to any other component of the formulation.Therefore 1-phenylazo-2-naphthol (CAS no-842-07-9) was considered to be a skin sensitizer in gunieapig.

On the basis of available information form key and supporting study of target, the test substance can be considered as sensitising to the skin.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Basis of available information for the target substance 1-phenylazo-2-naphthol (CAS no-842-07-9), the test substance can be considered as sensitising to the skin according to the GHS classification .