1,3,5-Naphthalenetrisulfonic acid, 7-[2-[2-[2-[5-cyano-4-methyl-2,6-bis[(4-sulfophenyl)amino]-3-pyridinyl]diazenyl]-4-(2-naphthalenyl)-5-thiazolyl]diazenyl]-, lithium sodium salt (1:?:?)

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Preliminary COD determination 2005-09-21. Study test phase 2005-09-23 to 2005-10-21. Study report signed 2006-01-26.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Meets the criteria for classification as Reliable without restriction according to Klimisch et al (1997)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 835.3110 (Ready Biodegradability)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

471-980-9

EC Name:

-

Cas Number:

1016986-95-0

Molecular formula:

Hill formula: C42 H24 Lim N9 Nan O15 S6 m+n=5 3=

IUPAC Name:

7-{2-[2-(2-{5-cyano-4-methyl-2,6-bis[(4-sulfophenyl)amino]pyridin-3-yl}diazen-1-yl)-4-(naphthalen-2-yl)-1,3-thiazol-5-yl]diazen-1-yl}naphthalene-1,3,5-trisulfonic acid trilithium hydride disodium hydride

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, predominantly domestic (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge: Final effluent stage from Severn Trent Water plc sewage treatment plant at Loughborough, Leceistershire, UK
- Storage conditions: The effluent was filtered through coarse filter paper and the filtrate maintained on continuous aeration at 21 deg. C
- Concentration of sludge: Test media was innoculated with sewage treatment micro-organisms at 1 drop of innoculum per litre

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

5 mg/L

Based on:

act. ingr.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: The culture medium used in this study was that recommended in the OECD guidelines.
- Test temperature: 20 deg. C

TEST SYSTEM
- Number of culture flasks/concentration: Sufficient bottles were prepared to allow a single oxygen determination per bottle with duplicate bottles for each test medium at each sampling point.
- Measuring equipment: Dissolved oxygen determined using a YSI 54A dissolved oxygen meter and BOD probe.

SAMPLING
- Sampling frequency: Dissolved Oxygen concentrations for each test medium were determined on days 0, 3, 5, 7, 11, 14, 18, 21, 24 and 28.

CONTROL AND BLANK SYSTEM
- Inoculum blank: A control consisting of inoculated culture medium
- Toxicity control: The test substance (5.0 mg ai/l) plus the standard reference material (1.5mg/l sodium benzoate) in inoculated culture medium

Reference substance

Reference substance:

benzoic acid, sodium salt

Remarks:

3.0 mg ai/l

Results and discussion

Preliminary study:

The COD of the test substance was determined to be 1.27 mgO2/mg.

% Degradation

% Degradation 1

Parameter:

% degradation (O2 consumption)

Value:

7

Sampling time:

5 d

% Degradation 2

Parameter:

% degradation (O2 consumption)

Value:

11

Sampling time:

7 d

% Degradation 3

Parameter:

% degradation (O2 consumption)

Value:

11

Sampling time:

14 d

% Degradation 4

Parameter:

% degradation (O2 consumption)

Value:

11

Sampling time:

21 d

% Degradation 5

Parameter:

% degradation (O2 consumption)

Value:

11

Sampling time:

28 d

BOD5 / COD results

Results with reference substance:

Sodium benzoate attained 80% degradation after 14 days and 82% degradation after 28 days thereby confirming the suitability of the test method and culture conditions.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

other: not readily biodegradable

Conclusions:

It is concluded that in this study the test substance failed to meet the criteria for ready biodegradability.

Executive summary:

Introduction

This study was performed to assess the ready biodegradability of the test substance in an aerobic aqueous medium. The method was designed to be compatible with the following guidelines:

OECD Guidelines for Testing of Chemicals (1992) No. 301D, 'Reday Biodegradability; Closed Bottle Test'

Method C.4 -E of Commission Directive 92/69/EEC (Annex V of Council Directive 67/548/EEC)

US EPA Fate, Transport and Transformation Test Guidelines OPPTS 835.3110 Paragraph (o).

Results & Conclusions

The test substance attained 11% degradation after 28 days and therefore cannot be considered to be readily biodegradable under the terms and conditions of OECD Guideline No 301D.