Pentasodium 2,2'-((2,4-diamino-5-(4-methoxy-2-sulfophenylazo)-1,3-phenylene)bis(azo))bis(5-(2-(sulfonatooxyethyl)sulfonyl)benzenesulfonate

Endpoint summary

Description of key information

The data of the acute dermal toxicity, dermal irritation and skin sensitization test indicate little or low dermal absorption, owing to the fact that no irritating or sensitizing effects were observed. This is in accordance with the physico-chemical properties of Reactive Brown F05‑0209. Oral resorption of the substance is probably also restricted due to the low log Kow of <-7 since most substances with a log Kow < 0.5 are only marginally resorbed.

Key value for chemical safety assessment

Bioaccumulation potential:

no bioaccumulation potential

Additional information

The assessment of the toxicokinetic properties of Reactive Brown F05-0209 given below is based on the results obtained for the following toxicological end-points with simultaneous reference to physico-chemical data such as solubility in various solvents and log Pow:

- acute oral toxicity

- acute dermal toxicity

- skin irritation

- eye irritation

- skin sensitization

- subacute (28 day) oral toxicity

- bacterial reverse mutation test

- chromosome aberration test in vitro

Reactive Brown F05-0209 has a molecular weight of 1177 g/mol, a water solubility of 145.8 g/L (66.3 mg/L for active ingredient) and a log Kow of <-7. The medial lethal dose (LD50) of Reactive Brown F05-0209 after oral or dermal administration to rats is above 2000 mg/kg body weight. Testing for skin irritating properties in rabbits showed no signs of irritation; however, slight opacity of the cornea was observed during the first week after test substance administration, leading to a classification for eye irritation Cat 2. Testing for skin sensitizing properties according to the method of Magnusson & Kligman showed no evidence for skin sensitization properties. In the 28-d study a NOEL of 1000 mg/kg bw was determined. The apparent dose-dependent increase in total bilirubin is the only indication of an absorption of the test substance, as the staining of the blood serum with the dye is known to interfere with the assay.

In the Ames Test the substance did not cause any relevant increases in the number of revertant colonies with any of the tester strains and is assessed to be non-mutagenic. In the chromosome aberration study in vitro with CHO-KI cells no relevant reproducible enhancement of metaphases with aberrations outside the range of the solvent control was found with any of the concentrations used, either with or without metabolic activation by S9-mix indicating that the substance is not clastogenic in this in vitro test system.

The data of the acute dermal toxicity, dermal irritation and skin sensitization test indicate little or low dermal absorption, owing to the fact that no irritating or sensitizing effects were observed. This is in accordance with the physico-chemical properties of Reactive Brown F05‑0209. Oral resorption of the substance is probably also restricted due to the low log Kow of <-7 since most substances with a log Kow < 0.5 are only marginally resorbed.

As Reactive Brown F05-0209 is an azo dye, partial metabolic cleavage by bacterial azo reductases in the intestine resulting in more hydrophilic amines seems to be likely. In summary based on the high water solubility, low log Kow and the results obtained in various toxicological examinations it can be concluded that Reactive Brown F05-0209 does not show any toxicokinetic peculiarity.