Tetra(sodium/potassium)-7-[(E)-{2-acetamido-4-[(E)-(4-{[4-chlor-6-({2-[(4-fluor-6-{[4-(vinylsulfonyl)phenyl]amino}-1,3,5-triazin-2-yl)amino]propyl}amino)-1,3,5-triazin-2-yl]amino}-5-sulfonato-1-naphthyl)diazenyl]-5-methoxyphenyl}diazenyl]-1,3,6-naphthalintrisulfonate

Endpoint summary

Description of key information

By the nature of their design and use, textile dyes are not intended to be readily biodegradable as this would assist in the rapid destruction of the dyestuff, rendering it unfit for purpose. As such, it is accepted that such substances are not readily biodegradable under relevant environmental conditions. A published study (Pagga & Brown, 1986) describes the results of the testing of 87 dyestuffs in short-term aerobic biodegradation tests. The authors of this publication concluded that dyestuffs are very unlikely to show any significant biodegradation in such tests and that 'there seems little point in carrying out such test procedures’ on dyestuffs. There are ISO, European, American (AATCC) and national standards available for the colour fastness of dyes. Dyes are required to have specific fastness properties. If the dyes were biodegradable, it would not be possible for them to have these fastness properties.

References:

Pagga U, Brown D (1986) The degradation of dyestuffs: Part II. Behaviour of dyestuffs in aerobic biodegradation tests. Chemosphere 15: 479-491.

Additional information

Study reports have been available for the ready biodegradability test, inherent biodegradability test, hydrolysis as a function of pH and adsorption / desorption test. The results are summarized as below:

The ready biodegradability test was performed over 28 days according to EU Commission Directive 92/69/EEC, C.4 -D (1992) and OECD Guideline for Testing of Chemicals No. 301 F (1992). The test item is not ready biodegradable under the valid test conditions within 28 days.

The inherent biodegradability test was investigated over 28 days based on the OECD Guideline for Testing of Chemicals No. 302 C (1981). There was no inhibitory effect on the activity of activated sludge microorganisms from the result of toxicity control. At the end of the 28-day test period, the mean biodegradation of test item amounted to 13 % without nitrification and 8 % with nitrification. Consequently, test item is not biodegradable under the valid test conditions within 28 days.

The hydrolysis as a function of pH was performed according to OECD Guideline for Testing of Chemicals No. 111 (2004) and EEC Directive 92/69, Section C.7 (1992). The test results showed that the test substance at pH 4 has a half-life period of 206 hours (9 days) at 25 ℃, at pH 7 is stable with a half-life of more than one year at 25 ℃, and at pH 9 has a half-life period of 867 hours (36 days) at 25 ℃.

The determination of the adsorption coefficient (KOC) of test item was performed according to the OECD Guideline for the Testing of Chemicals, No. 121 and the EC Directive 2001/59, C.19. The log of the adsorption coefficient (KOC) of test item was estimated to be log KOC<1.25 which is equal to a KOC value of <18 using the HPLC method. This value indicates that the test item will not be adsorbed by organic carbon in soil. 

The information from biodegradation and hydrolysis tests is sufficient for the Persistence assessment. Thus, simulation tests of biodegradation were not required. In accordance with Column 2 of REACH, Annexes IX tests for bioaccumulation do not need to be conducted if the substance has a low potential for bioaccumulation, due to the low logKOW (logKOW < 3). Thus, no additional test was required for the bioaccumulation test.