reaction mass of: trisodium 3-(5-(2,6-difluoropyrimidin-4-ylamino)-2-sulfonatophenylazo)-5-(4-fluoro-6-morpholin-4-yl-1,3,5-triazin-2-ylamino)-4-hydroxy-2,7-naphthalenedisulfonate; trisodium 3-(5-(4,6-difluoropyrimidin-2-ylamino)-2-sulfonatophenylazo)-5-(4-fluoro-6-morpholin-4-yl-1,3,5-triazin-2-ylamino)-4-hydroxy-2,7-naphthalenedisulfonate

Endpoint summary

Description of key information

Based on the results of the available data Reactive Red FC73270 did not show a conspicuous toxicokinetic behaviour. The dye has a very low oral or dermal absorption rate and does not accumulate in tissues or organs.

Key value for chemical safety assessment

Bioaccumulation potential:

no bioaccumulation potential

Additional information

Toxicokinetic parameters such as absorption, distribution, metabolism and excretion form the essential toxicological profile of a substance. The evaluation of the toxicokinetic properties of Reactive Red FC73270 is based on the results of subsequent toxicological endpoints: acute oral toxicity, acute dermal toxicity, skin irritation, sensitization, Ames test, In vitro cytogenetic study, in vivo micronucleus assay, subacute oral toxicity, with the additional inclusion of physico-chemical data, such as solubility, partition coefficient and hydrolytic stability.

Toxicological profile:

Administration of a single dose of 2000 mg/kg body weight of the test substance in the acute oral toxicity study did not cause any clinical signs or mortality. Red discoloured faeces and diarrhoea were observed. No other macroscopic effects were noted. Hence, the oral LD50 lies above 2000 mg/kg body weight in rats. The dermal treatment with 2000 mg/kg body weight also led to no toxicologically relevant effects, resulting in a dermal LD50 of above 2000 mg/kg body weight in rats. Based on the results of acute dermal toxicity study as well as the skin irritation and sensitisation studies, and the significantly hydrophilic properties Reactive Red FC73270 has no significant dermal absorption potential.

Reactive Red FC73270 was not mutagenic in the Ames test with and without metabolic activation. Reactive Red FC73270 induced chromosome aberrations in V79 hamster cells in vitro without metabolic activation, however, was negative with metabolic activation, as often seen in vinyl-sulphone dyes. It was negative in an in vivo Micronucleus test proving that the test substance is not clastogenic.

In the subacute (28 days) oral toxicity study daily doses up to 1000 mg/kg body weight in rats caused no compound-related lethality. Body weight gain, haematological and clinical chemical parameters, as well as specific organ weights were unaffected. Histopathological examinations showed inflammatory reactions in the fundus of the glandular stomach in the males and females of the high dose group. The glandular cells themselves were not affected. This effect was not associated with a destructive process and was proved to be reversible in the recovery group. Consequently, this effect is not of toxicological significance. Macroscopically, a brownish to olive coloration of the kidney in the middle and high dose groups was found which was not completely reversible within the 14 days recovery time. However, as no histopathological correlate was found, this effect is considered as of no toxicological significance. On the basis of the available data, a NOAEL of 250 mg/kg /body weight was determined.

Assessment

Based on the results of the available data Reactive Red FC73270 did not show a conspicuous toxicokinetic behaviour. The dye has a very low acute toxic potential and no or only a very low dermal absorption potential. The results of the subacute study demonstrate a limited absorption by the gastrointestinal tract, which manifested in the discoloration of faeces and urine. Due to the hydrophilic nature, a potential to bioaccumulate can be excluded. The inflammatory changes in the glandular stomach have been regarded as a local effect and thus do not influence the assessment of the toxicological potential. Reactive Red FC73270 does not metabolise to genotoxic structures.