Barium 3-hydroxy-4-[(4-methyl-2-sulphonatophenyl)azo]-2-naphthoate

Endpoint summary

Description of key information

Experimental data is available for the analogue Pigment Red 48:1 (7585-41-3) which differs from Pigment Red 57:2 by one additional chlorine at the sulfonic aromatic amine part. It is concluded that Pigment Red 57:2 is of low acute toxicity after oral, dermal or inhalation toxicity.
Pigment Red 48:1 caused no mortality and no signs of intoxication at doses between 5000 and 10000 mg/kg bw in rats after single gavage application and an observation period of seven or eight days (Ciba 1972, BASF AG 1974a). 
No mortality and no indication of systemic toxicity was observed in rats after single dermal application of a dose of 2500 mg/kg bw Pigment Red 48:1 (BASF AG 1974b). The study was performed following a procedure comparable to OECD testing guideline 402.
Acute inhalation exposure to aerosol at a concentration of 4.76 mg/L (MMAD 1.4  μm / GSD 0.34) caused mortality in one of ten rats (Capelle 1993) as assessed in a GLP compliant study following OECD testing guideline 403.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

5 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 500 mg/kg bw

Additional information

No experimental data is available for Pigment Red 57:2. Therefore, data on the analogue Barium salt Pigment Red 48:1 is taken into account. This pigment contains an additional chlorine at the phenyl ring which has no impact on acute toxicity.

Two valid rat studies are available for acute oral toxicity. In one study, a product of adequate purity was tested at doses of up to 6400 mg/kg bw (BASF 1974). In the other study, a commercial product of unknown purity was tested at doses of 5000 and 10000 mg/kg bw (Ciba 1972). The procedures are comparable to OECD testing guideline 423 (2001) with the exception that the observation period is only 7 or 8 days rather than 14 days and that no necropsy was performed in the older study. The studies were performed prior to introduction of GLP, but are described in adequate detail.

 

The key study for acute dermal toxicity (BASF AG 1974b) was performed in rats following a protocol which is comparable to OECD testing guideline 402 (1987). It was performed prior to the introduction of GLP but is documented adequately. Test material purity was adequate. No indication of adverse findings was observed during the 14-day observation period. Remnants of coloured test material interfered with the scoring of local irritation in all ten animals.

 

The key study for acute inhalation toxicity (Capelle 1993) was performed in rats following OECD testing guideline 403 and GLP. Pigment Red 48:1 with adequate purity was used and the particle size was in the respirable range as appropriate for rats. One male was found dead 3h after the start of the exposure. During exposure animals commonly showed wet fur, laboured, decreased or increased respiratory rate and red staining of the fur from the test material. On removal from the chamber and one hour after completion of exposure additional signs of toxicity noted in surviving animals included hunched posture, lethargy, pilo-erection, gasping and noisy respiration, ptosis and ataxia. One female showed tiptoe gait one hour after completion of exposure. Signs of toxicity including respiratory abnormalities were apparent for several days after exposure but with the exception of stained fur surviving animals appeared normal six to eight days after exposure.The male that died during the study showed swollen and abnormally dark lungs and pink contents in the small intestine at necropsy. No abnormalities were detected in surviving animals at the end of the study.

 

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 1272/2008. As a result the substance is not considered to be classified for acute oral, dermal or inhalation toxicity under Regulation (EC) No. 1272/2008.