1-(4-methyl-2-nitrophenylazo)-2-naphthol

Endpoint summary

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:

1992

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

Old study available from the time where the non-LLNA study was not available

Species:

guinea pig

Strain:

other: Hoe: DHPK (SPFLac)

Sex:

female

Route:

intradermal and epicutaneous

Vehicle:

petrolatum

Route:

epicutaneous, semiocclusive

Vehicle:

petrolatum

No. of animals per dose:

10 amimals in the treatment group and 5 animals in the control

Reading:

1st reading

Hours after challenge:

48

Group:

test chemical

Dose level:

1% C.I. Pigment Red 3 in petrolatum

No. with + reactions:

4

Total no. in group:

10

Clinical observations:

Very slight up to well-defined erythema and very slight oedema were observed in four animals

Remarks on result:

other: see Remark

Remarks:

Reading: 1st reading. . Hours after challenge: 48.0. Group: test group. Dose level: 1% C.I. Pigment Red 3 in petrolatum. No with. + reactions: 4.0. Total no. in groups: 10.0. Clinical observations: Very slight up to well-defined erythema and very slight oedema were observed in four animals.

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

1% C.I. Pigment Red 3 in petrolatum

No. with + reactions:

1

Total no. in group:

10

Clinical observations:

One animal of the treated group showed very slight to well-defined erythema

Remarks on result:

other: see Remark

Remarks:

Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 1% C.I. Pigment Red 3 in petrolatum. No with. + reactions: 1.0. Total no. in groups: 10.0. Clinical observations: One animal of the treated group showed very slight to well-defined erythema.

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Executive summary:

Testing for sensitizing properties of Pigment Red 3 was performed in female Guinea pigs according to the method of Magnusson & Kligman.

Intra dermal induction was performed using 0.2% Pigment Red 2 in semi-liquid paraffin. Dermal induction was carried out with 5%, challenge treatment with 1% Pigment Red 3 in petrolatum.

Four animals of the treatment group showed a positive skin response after the first challenge procedure and one animal reacted after the second challange. If the effects observed at the first challange are due to sensitization, then equal or even stronger reactions would be expected after the second challenge procedure. Therefore, the reactions noted in the three other animals at the first challange are considered to be rather unspecific irritation effects than allergic reactions.

Based on the results of this study Pigment Red 3 is not considered to be a skin sensitizer.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Skin sensitisation

Skin sensitising potential of Pigment Red 3 was tested in female Guinea pigs. Four animals of the treatment group showed a positive skin response after the first challenge procedure and one animal reacted after the second challenge. If the effects observed at the first challange are due to sensitization, then equal or even stronger reactions would be expected after the second challange procedure. Therefore, the reactions noted in the three other animals at the first challenge are considered to be rather unspecific irritation effects than allergic reactions.

Based on the results of this study Pigment Red 3 is not considered to be a skin sensitizer.

The following information is taken into account for any hazard / risk assessment:

Pigment Red 3 has been tested in female Guinea pigs to assess the sensitising potential of the test item. Based on the results of this study Pigment Red 3 is not considered to be a skin sensitizer.

Value used for CSA: not sensitising

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information:

Respiratory sensitisation

The following information is taken into account for any hazard / risk assessment:

Respiratory tract sensitisation:

Substance is not classified for this endpoint. The substance is considered not to exert any sensitizing effects on the respiratory tract; when aerosolized in respirable form, the substance is considered likely to behave like an inert dust.

Non-human information: This information is not available.

Justification for classification or non-classification

Pigment Red 3 did not show skin sensitising properties in female Guinea pigs. No skin reactions were seen in 28 healthy young female volunteers in a 48 hour patch test with 1% C.I. Pigment Red 3 in petrolatum (Kgzuka et al.1980)

However allergic skin reactions or case reports of acute contact dermatitis to Pigment Red 3 have been described in the literature. Slight erythema or erythema with edema were observed in patients with pigmented cosmetic dermatitis in patch or photopatch tests with C.I. Pigment Red 3 after application for 48 or 72 hours. Positive reactivity was 34.2% (13/38) (Sugai et al.1977). The reddening and swelling of the skin were seen in five of 155 patients with cosmetic dermatitis in a 48-h path tests with 5% C.I. Pigment Red 3 in polyethylene glycol; slight reddening was seen in another 25 of the patients (MJCDRG 1978). In a patch test, negative reaction was observed with 1% Pigment Red 3 (in petrolatum) in the skin of patients who were suffered from dermatitis caused by Brilliant Lake Red R.

It can reasonably be deduced that Pigment Red 3 does not cause respiratory tract sensitization and thus does not have to be classified according to the criteria laid down in the EU Dangerous Substances Directive (67/548/EEC) and in the EU Classification Labelling and Packaging Regulation (1272/2008/EC), because

- Pigment Red 3 did not cause skin sensitization, and

- it is unlikely that Pigment Red 3 can interact with the immune system due to its extremely low solubility in water and n-octanol.