Sodium hydrogen 4-amino-5-hydroxynaphthalene-2,7-disulphonate

Endpoint summary

Additional information

The Ames test was conducted under Japanese Guidelinesunder the Chemical Substances Control Law (Screening Mutagenicity Testing of Chemicals)and OECD TG 471 in compliance with GLP (MHW, Japan, 1994). The mutagenicity was examined twice in four Salmonella typhimuriumstrains, TA98, TA100, TA1535 and TA1537, and in an Escherichia coli WP2uvrA,at concentrationsat 0, 312.5, 625, 1250, 2500, 5000 μg/plate (-S9 mix and +S9 mix; all strains).The doses apply to the test compound, and have not been recalculated to take account of the impurities (the purity of the testedsubstance:87.4 %).

In this study, the substance did not show any mutagenic activity in any bacterial strain with or without metabolic activation.The positive controls showed the expected positive results.

The chromosome aberration study was conducted under Japanese Guidelines under Chemical Substances Control Law (Screening Mutagenicity Testing of Chemicals)and OECD TG 473 in compliance with GLP (MHW, Japan, 1994). The Chinese hamster lung (CHL/IU) cells were treated withmonosodium 4-amino-5-hydroxynaphthalene-2,7-disulphonate(dispersed with 0.5% of CMC-Na aqueous solution) for 24 hr and 48 hr (continuous treatment) in the absence of metabolic activation at concentrations up to 2.20 mg/mL (ca. 50 % inhibition of cell growth), and 6 hr (short-term treatment) in the presence or absence of metabolic activation at concentrations up to 3.40 mg/mL (10 mM). Growth inhibition did not exceed 50 % up to 3.40 mg/mL with metabolic activation.The doses apply to the test compound, and have not been recalculated to take account of the impurities (the purity of the tested substance: 87.4 %).

Total number of cells with aberrations excluding gaps were 1, 0, 0 and 0 for 24 hr and 0, 0, 1 and 0 for 48 hr in the continuous treatment at 0, 0.55, 1.10 and 2.20 mg/mL, respectively, and 0, 0, 0 and 0 (without metabolic activation) and 0, 0, 0 and 1 (with metabolic activation) in the short-term treatement at 0, 0.85, 1.70 and 3.40 mg/mL, respectively. No increase in clastogenicity (structural chromosome aberration) or polyploidy was observed at any dose with or without metabolic activation. The positive control showed expected positive result.

Short description of key information:
In a bacterial mutation study using four strains of Salmonella typhimurium and an Escherichia coli WP2 uvrA strain, monosodium 4-amino-5-hydroxynaphthalene-2,7-disulphonate was negative with or without metabolic activation. In an in vitro chromosome aberration test using CHL/IU cells, monosodium 4-amino-5-hydroxynaphthalene-2,7-disulphonate was also negative with or without metabolic activation.

Endpoint Conclusion: No adverse effect observed (negative)