Ammonium 3-nitrobenzoate

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:

2017-05-10 - 2017-06-07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

OECD Guidelines for the Testing of Chemicals Part 301 F, adopted 17. Jul. 1992, „Manometric Respirometry Test“

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Commission Regulation (EC) No. 440/2008, Guideline C.4-D, adopted 30. May 2008 “Manometric Respirometry Test”

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Ammonium 3-nitrobenzoate

EC Number:

242-965-2

EC Name:

Ammonium 3-nitrobenzoate

Cas Number:

19328-56-4

Molecular formula:

C7H5NO4.H3N

IUPAC Name:

ammonium 3-nitrobenzoate

Constituent 2

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

water

Test material form:

liquid

Details on test material:

- Storage: Room Temperature (20 ± 5 °C)

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: The test item was stored in a tightly closed vessel at 18.0 – 22.5 °C.

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Activated sludge from a biologic sewage treatment plant was used. The chosen plant is treating mostly household sewage.
The sludge was taken from the activation basin of the ESN (Stadtentsorgung Neustadt) sewage treatment plant, Im Altenschemel, NW-Lachen-Speyerdorf.
Date of collection: 10. May 2017, batch no: 20170510.
- Pretreatment: The sludge was filtrated, washed with tap water 2x, then washed with and re-suspended in test medium. It was then aerated.
- Concentration of sludge: The dry matter was determined as 3800 mg suspended solids/L.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

337 mg/L

Based on:

test mat.

Remarks:

337 mg/L Ammonium-3-nitrobenzoate as aqueous solution.

Initial test substance concentration 2

Initial conc.:

100.09 mg/L

Based on:

ThOD

Remarks:

with nitrification to nitrate

Initial test substance concentration 3

Initial conc.:

58.6 mg/L

Based on:

ThOD

Remarks:

without nitrification

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium:
Stock solutions
a) 8.5 g KH2PO4, 21.75 g K2HPO4, 33.4 g Na2HPO4 x 2 H2O, 0.5 g NH4Cl and 1000 mL H2O demin. ad
b) 27.5 g CaCl2 x 2H2O and 1000 mL H2O demin. ad
c) 22.5 g MgSO4 x 7H2O and 1000 mL H2O demin. ad
d) 0.25 g FeCl3 x 6H2O, 0.4 g Na2EDTA x 2H2O and 1000 mL H2O demin. ad
Test Medium
10 mL solution a
1 mL solution b
1 mL solution c
1 mL solution d
1000 mL H2O demin. ad
- Test temperature: 20.1 – 21.3 °C
- pH adjusted: yes, pH was adjusted to 7.3 – 7.4
- Suspended solids concentration: 24.9 mg/L

TEST SYSTEM
- Number of culture flasks/concentration: 3 (test item, medium and inoculum)
- Other:
Volume of test vessels: 500 mL
Volume test solution: 250 mL (toxicity control flask 125 mL)

CONTROL AND BLANK SYSTEM
Number of control flasks: 3 (medium and inoculum)
Number of positive control flasks: 3 (sodium-benzoate, medium and inoculum)
Number of test vessels: 3 (Ammonium-3-nitrobenzoate solution, medium and inoculum)
Abiotic control: 1 (Ammonium-3-nitrobenzoate solution and 10 mL 1 % HgCl2 solution/L)
Toxicity control: 1 (200 mg/L ThOD, 100 mg/L THOD each of test item and positive control)

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

Test performance:

The validity criteria were met, controls gave the appropriate results.

% Degradation

% Degradation 1

Key result

Parameter:

% degradation (CO2 evolution)

Value:

81

Sampling time:

17 d

Remarks on result:

other: readily biodegradable

Remarks:

The 10-day-window began on day 7, at its end (day 17), 81 % were reached, staying above the pass level of 60% given in the OECD guideline.

% Degradation 2

Key result

Parameter:

% degradation (CO2 evolution)

Value:

90

Sampling time:

19 d

Remarks on result:

other: readily biodegradable

Remarks:

The 10-day-window began on day 7 (this is stated as lag phase). At its end (day 17), 81 % were reached, staying above the pass level of 60% given in the OECD guideline. The degradation phase is defined as interval between the end of the lag phase and the reaching of 90 %. This was reached on day 19.

% Degradation 3

Key result

Parameter:

% degradation (CO2 evolution)

Value:

100

Sampling time:

28 d

Remarks on result:

other: readily biodegradable

Details on results:

Assessment
The degree of biodegradation reached 100 % after 28 days.
The 10-day-window began on day 7 (this is stated as lag phase). At its end (day 17), 81 % were reached, staying above the pass level of 60% given in the OECD guideline.
The degradation phase is defined as interval between the end of the lag phase and the reaching of 90 %. This was reached on day 19.
Therefore, when applying the 10-day-window, the test item Ammonium-3-nitrobenzoate is readily biodegradable following OECD 301F/EU C.4-D.

BOD5 / COD results

Results with reference substance:

Parameter Criterion Found Assessment
Degradation of positive control > 60% < 14 days 3 days valid
Degradation of positive control > 40% < 7 days 1 day valid

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The study was performed according to OECD TG301F and EU Method C.4-D (GLP) without deviations and is therefore considered to be of the highest quality (reliability Klimisch 1). The validity criteria of the test system are fulfilled.
The degree of biodegradation reached 100 % after 28 days.
The 10-day-window began on day 7 (this is stated as lag phase). At its end (day 17), 81 % were reached, staying above the pass level of 60% given in the OECD guideline.
The degradation phase is defined as interval between the end of the lag phase and the reaching of 90 %. This was reached on day 19.
Therefore, when applying the 10-day-window, the test item Ammonium-3-nitrobenzoate is readily biodegradable following OECD 301F/EU C.4-D.

Executive summary:

The Ready Biodegradability of Ammonium-3-nitrobenzoate was determined under aerobic conditions in the Manometric Respirometry Test following OECD 301F / EU C.4-D under GLP.

The test item Ammonium-3-nitrobenzoate was tested using a concentration of nominal 337 mg test item/L (equivalent to a theoretical oxygen demand of 100.09 mg O2/L). Activated sludge was used as inoculum. The test was left running for 28 days. All validity criteria were met. The positive control reached the pass level of 60% on day 3 (criterion: <=14).

The following data could be determined for the test item Ammonium-3-nitrobenzoate:

10-day-window: day 7 – 17

degradation at the end of 10-day-window: 81 %

degradation at the end of the test: 100 %

Therefore, when applying the 10-day-window, Ammonium-3-nitrobenzoate is classified as readily biodegradable following OECD 301F and EU C.4-D.