Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

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. There are ISO, European, American (AATCC) and national standards 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.

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.

Nevertheless, biodegradbility of FAT 36038 was tested in several studies over the years.

In a study performed to determine the biological elimination of FAT 36038/C according to a guideline which is equivalent or similar to OECD test guideline 303 A (confirmatory test),at the end of 28 days, the biological elimination of FAT 36038/C was found to be 98 % (TOC removal).

Over several studies, the biological oxygen demand (BOD5) and chemical oxygen demand (COD) values for FAT 36038 were determined. The BOD5/COD quotient was found to be less than 0.5 in each case, therefore, the substance is considered to be not indicative of rapid degradation.

Taking all data into consideration, it can be concluded that FAT 36038 is not readily biodegradable. 

Additional information