Benzoic acid, 3-amino-4-methyl-, methyl 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:

31..01.2012 - 15.04.2012

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

methyl 3-amino-4-methylbenzoate

EC Number:

606-067-8

Cas Number:

18595-18-1

Molecular formula:

C9H11NO2

IUPAC Name:

methyl 3-amino-4-methylbenzoate

Details on test material:

Identification: AMN107B1
Molecular formula: C9H11N02
Molecular weight: 165.19
CAS Number: 18595-1 8-1
Description :Off-white powder
Batch: CHAD0401
Purity: 99.4%
Test substance storage: At room temperature in the dark
Stability under storage conditions: Stable
Expiry date: 31 March 2005

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

15.6 mg/L

Based on:

test mat.

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (CO2 evolution)

Value:

0

Sampling time:

7 d

% Degradation 2

Parameter:

% degradation (CO2 evolution)

Value:

2

Sampling time:

98 d

% Degradation 3

Parameter:

% degradation (CO2 evolution)

Value:

10

Sampling time:

29 d

Details on results:

Theoretical C02 production
The 'Theoretical C02 production (ThC02) of AMNI07 B1 was calculated to be 2.40 mg C02/mg.
Both test bottles contained 31.1 mg AMN107 B1 in 2 litres test medium. Hence, the theoretical
C02 production following complete degradation was 74.6 mg per 2 litres for both test bottles.
The positive control contained 80.0 mg sodil~ma cetate (ThC02= 1.07 mg C02/mg) in 2 litres test
medium, resulting in a theoretical C02 production following complete degradation of 85.6 mg per 2 litres. The toxicity control contained 80.0 mg sodium acetate and 31 :I mg AMN 107 B1 in 2 litres of test medium. Hence, the theoretical C02 production following complete degradation of AMN 107 B1 plus sodium acetate was 160.2 mg per 2 litres.

Selection of test concentration
In an earlier modified Sturm test (not reported), AMN107 B'l was tested in duplicate at 37 mg per 2 litres, corresponding to 12 mg TOCII. In the toxicity control of this experiment less than 25%
degradation occurred within 14 days (1 8%, based on ThCO,). Therefore, the final experiment was performed at a lower concentration (1 0 mg TOCII).

Biodegradation
The relative degradation values calculated from the measurements performed during the test
period revealed no significant degradation of AMN107 BI . In the toxicity control more than 25% degradation occurred within 14 days (38%, based on ThC02). Therefore, the test substance was assumed not to inhibit microbial activity.

Monitoring of temperature and pH
The temperature recorded in a vessel with water in the same room varied between 21.7 and
22.5"C. pH values of the different test media are 7.6 – 7.9

Conclusion
AMN107 B1 was not readily biodegradable under the conditions of the modified Sturm test
Presently performed.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The substance is not readily biodegradable.

Executive summary:

Determination of 'ready' biodegradability: carbon dioxide (C02) evolution test (modified Sturm test)

with AMN107 B1.

The study procedure was based on EEC directive 92/69, C.4-C, December 1992, OECD guideline

No. 30'1 B July 17, 1992 and IS0 Standard 9439 (1999).

The Theoretical C02 production (ThC02) of AMN'l07 BI was calculated to be 2.40 mg CQ2/mg.

AMN107 B1 was an off-white powder with a purity of 99.4%. The water solubility of AMN107 B1

was 0.43 gll at 19.8 rt 0.8 "C (NOTOX Project 431 551). AMN107 B1 was tested in duplicate at

31 mg per 2 litres, corresponding to 10 mg TOCII. The organic carbon content was based on the

molecular formula.

The study consisted of six bottles:

- 2 blank controls (no test material),

- 2 test bottles (AMNI 07 Bl , 15.6 mg/l),

- 1 positive control (sodium acetate, 40 mg/l) and

- 1 toxicity control (AMN107 Bl, 15.6 mgll; plus sodium acetate, 40 mgll).

Since AMNI 07 B1 was not sufficiently soluble to allow preparation of an aqueous solution at a

concentration of 1 g/l, weighed amounts of AMN 107 B1 were added to the test bottles containing

medium with microbial organisms and mineral components. To this end, 10 ml of Milli-RO water

was added to each weighing bottle containing the test substance. After vigorous mixing the

resulting suspension was added quantitatively to the test medium. The test solutions were

continuously stirred during the test, to ensure optimal contact between the test substance and the

test organisms.

The relative degradation values calculated from the measurements performed during the test

period revealed no significant degradation of AMN 107 B1.

In the toxicity control, AMN107 B1 was found not to inhibit microbial activity.

Since all criteria for acceptability of the test were met, this study was considered to be valid.

In conclusion, AMNl07 B'l was not readily biodegradable under the conditions of the modified

Sturm test presently performed.