.beta.-Alanine, N-[2-chloro-4-[2-(4-nitrophenyl)diazenyl]phenyl]-, 2-[2-(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)ethoxy]-2-oxoethyl ester

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:

From February 19 to March 22, 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Version / remarks:

1992

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

Version / remarks:

1992

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Yellow 981

IUPAC Name:

Yellow 981

Test material form:

solid: particulate/powder

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Principle electro-chemical analysis process:
The biodegradation process consumes the dissolved oxygen in the liquid and generates CO2. The CO2 is adsorbed by soda lime and the total pressure decreases in the airtight test flasks. The pressure drop is detected and converted into an electrical signal by means of an electrode type manometer. The consumed oxygen is replaced by electrolytically generated oxygen from a copper sulfate solution.
Test duration: 28 days
Light regimen: darkness
Test temperature: 22 °C
pH: prior to test start the pH (measured in all test flasks after the addition of the activated sludge inoculum) was 7.4. At the end of incubation the pH was measured again in all test flasks.

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

% Degradation 1

Parameter:

other: % biodegradation: BOD / ThOD NH4 × 100

Value:

< 10

Sampling time:

28 d

Remarks on result:

other: not significant biodegradation

% Degradation 2

Parameter:

other: % biodegradation: BOD / ThOD NH3 × 100

Value:

< 10

Sampling time:

28 d

Remarks on result:

other: not significant biodegradation

BOD5 / COD results

BOD5 / COD

BOD5 / COD 1

Parameter:

ThOD

Value:

1.25 mg O2/g test mat.

Remarks on result:

other:

Remarks:

without nitrification

BOD5 / COD 2

Parameter:

ThOD

Value:

1.71 mg O2/g test mat.

Remarks on result:

other:

Remarks:

with nitrification

Results with reference substance:

Sodium benzoate: 83 % biodegradation within 14 days; 82 % within 28 days

Any other information on results incl. tables

Abiotic control: no significant degradation of the test item occurred in the abiotic control under the test conditions.

The biodegradation rate in the toxicity control showed a similar course of biodegradation over the 28-day exposure period as the two procedure controls containing the reference item, only.

Within 14 days of exposure, a biodegradation rate of 50 % and 43 % was observed based on the ThOD_NH4 and the ThOD_NO3, respectively. Thus, according to the test guidelines, the test item had no inhibitory effect on activated sludge microorganisms because the biodegradation rate in the toxicity control was > 25 % within 14 days.

Applicant's summary and conclusion

Interpretation of results:

not readily biodegradable

Conclusions:

No significant degradation in 28 days.