p-aminobenzamide

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: inherent biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The Zahn-Wellens test was conducted according to national standard (DIN 38 412, Part 25, 1984).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test)

Deviations:

yes

Remarks:

In the today's methods no industrial but only municipal wastewater sludge is used and the concentrations of the test substances and sludge are some lower.

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.9 (Biodegradation: Zahn-Wellens Test)

Deviations:

yes

Remarks:

In the today's methods no industrial but only municipal wastewater sludge is used and the concentrations of the test substances and sludge are some lower.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

p-aminobenzamide

EC Number:

220-612-3

EC Name:

p-aminobenzamide

Cas Number:

2835-68-9

Molecular formula:

C7H8N2O

IUPAC Name:

4-aminobenzamide

Study design

Oxygen conditions:

not specified

Inoculum or test system:

activated sludge, industrial (adaptation not specified)

Details on inoculum:

Industrial origin, no data whether adapted or not to test item

Duration of test (contact time):

17 d

Initial test substance concentration

Initial conc.:

303 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

Preparation of the stock solution: 0.5 g/L test substance dissolved in deionized water, pH adjusted from 4.3 to 2.5; the batch was stirred over 24 h at room temperature and finally adjusted to pH 7.2.
DOC analysis of the stock solution: 303 mg C/L (theor.: 308.8 mg C/L)
COD analysis of the stock solution: 805 mg O2/L (theor.: 822.6 mg O2/L)

Reference substance

Reference substance:

diethylene glycol

Remarks:

271.6 mg DOC/L

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (DOC removal)

Value:

0

Sampling time:

3 h

% Degradation 2

Parameter:

% degradation (DOC removal)

Value:

14

Sampling time:

3 d

% Degradation 3

Parameter:

% degradation (DOC removal)

Value:

85

Sampling time:

7 d

% Degradation 4

Parameter:

% degradation (DOC removal)

Value:

94

Sampling time:

10 d

% Degradation 5

Parameter:

% degradation (DOC removal)

Value:

98

Sampling time:

17 d

BOD5 / COD results

Results with reference substance:

3 h: 25 %
3 d: 31 %
7 d: 84 %
10 d: 95 %

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

inherently biodegradable

Conclusions:

The test item is inherently and completely biodegradable.

Executive summary:

Testing of p-aminobenzamide for inherent biodegradability was performed in the Zahn-Wellens test. The results of testing revealed that the substance is inherently and completely biodegradable. The degradation of the reference substance was in the demanded range and caused a DOC reduction of more than 90 % within 10 days.