Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Basic Blue 145 is considered to be not readily biodegradable.

Additional 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 Basic Blue 145 was tested over the years in several biodegradability studies.

- In an inherent biodegradability study (OECD 302B), Basic Blue 145 was found to biodegrade upto 58 % after 28 days.

- In ready biodegradabilty studies (OECD 301A and OECD 301C), the biodegradation found was 0 %.

- BOD5 and COD value of 31 and 1856 mg O2/g test mat. was determined for FAT 31064/F. Based on the BOD5/COD quotient which is not >0.5, the substance is not indicative of rapid degradation.

Taking the data from degradation tests and BOD5/COD quotient into account, Basic Blue 145 is considered to be not readily biodegradable.