Sodium 4-[4-[[2-methyl-4-[[(p-tolyl)sulphonyl]oxy]phenyl]azo]anilino]-3-nitrobenzenesulphonate

Endpoint summary

Description of key information

No bioaccumulation potential expected.

Key value for chemical safety assessment

Bioaccumulation potential:

no bioaccumulation potential

Additional information

Acid Orange 067 is a orange-red organic powder, dyestuff. It is not toxic/harmful for short-term exposures and it is not skin/eye irritating. It is not able to cause skin sensitization. No genotoxic activity has been observed in specific experiments performed. The Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test did not evidence any reason of concern. Therefore, mechanisms of bioactivation leading to adverse effects are not expected to occur.

 There are no specific studies or specific literature data on toxicokinetics and metabolism, thus available information about the substance has been taken into account, avoiding further tests.

Because of the physical state and the characteristic particle size distribution, inhalation is not an appropriate route of exposure.

 

During the acute oral toxicity experiments, the treatment did not produce changes detected in health condition; faeces were stained orange after one day. During the subacute oral test, yellowish colour of stool was observed in the bedding material of all animals administered with 1000 mg/kg bw/day from Day 6 up to the termination of the study. Since Acid Orange 067 showed a slightly alkaline pH is solution, it may be expected that possible absorption would take place in the intestine, rather than in stomach.

Yellowish colour of the faeces was attributed to the elimination of test item or its metabolite by the gastrointestinal tract. There are some possible reason explaining the fact that only at the highest tested concentration stained stools were observed. For example, a saturation level may had been reached, at the highest tested concentration, so that the organism was not able to further transform/absorb additional amount of substance; however, it may be also due to the substance concentration and colour intensity, which impacted the reading at the lowest dose levels.

 

Acid Orange 067 has a structure with different chemical groups, which, it is supposed, may undergo to metabolic reactions; however, on the basis of the available information a conclusion cannot be traced, neither from qualitative, either from rate point of view. The only consideration that may be proposed is that, taken into account the absence of significant effects directly attributable to the test item administration and the observed stained faeces, it may be supposed that only few rates of substance can be absorbed or that it can be metabolised into a easily eliminable compound(s), not significantly harmful/toxic. In any case, processes of bioactivation, which may increase the substance toxicity, can be excluded.