Dimethyl 2-nitroterephthalate

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:

2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: well performed OECD study with GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dimethyl 2-nitroterephthalate

EC Number:

226-134-1

EC Name:

Dimethyl 2-nitroterephthalate

Cas Number:

5292-45-5

Molecular formula:

C10H9NO6

IUPAC Name:

dimethyl 2-nitroterephthalate

Details on test material:

purity:98.1 %
expiry: 2001-09-30

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

The activated sludge is maintained in an aerobic condition by aeration for four hours and then homogenized with a mixer. The sludge is filtered and the filtrate (3o mL) is subsequently used to initiate inocculation.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

25 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- test temperature: 23 - 24 °C
- pH: about 7.5
- pH adjusted: no


TEST SYSTEM
- Culturing apparatus: 5000 ml vessel (brown glass); test volume 3000 ml
- Measuring equipment: pH-meter; Corning pH 240
- Test performed in open system: no
- Details of trap for CO2 and volatile organics if used: Ba(OH)2 solution

CONTROL AND BLANK SYSTEM
- Inoculum blank: Nutrient solution and inoculum
- Functional control: Sodium acetate
- Toxicity control: test item plus reference substance

Reference substance

Reference substance:

other: sodium acetate

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (CO2 evolution)

Value:

6 - 7

Sampling time:

6 d

Remarks on result:

other: values of replicate 1 and 2

% Degradation 2

Parameter:

% degradation (CO2 evolution)

Value:

11 - 22

Sampling time:

14 d

Remarks on result:

other: values of replicate 1 and 2

% Degradation 3

Parameter:

% degradation (CO2 evolution)

Value:

11 - 30

Sampling time:

21 d

Remarks on result:

other: values of replicate 1 and 2

% Degradation 4

Parameter:

% degradation (CO2 evolution)

Value:

11 - 37

Sampling time:

28 d

Remarks on result:

other: values of replicate 1 and 2

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

other: not readily biodegradable

Conclusions:

base on the results of the OECD 301 B test, Nitro-DMT must be considered as not readily biodegradable

Executive summary:

The ready biodegradability was determined with a non adapted activated sludge with Nitro-DMT over a period of 28 days in the Modified Sturm Test (OECD 301B). The test item was tested in a concentration of 25 mg/L in duplicate and the biodegradation was followed by the titrimetric analysis of the quantity of CO2, which was produced by the respiration of the bacteria. The CO2 production was calculated as the percentage of total CO2, that the test item could have theoretically produced, based on the carbon composition.

After 28 days the biodegradation came to a level of 11 - 37 %.

Sodium acetate was used as functional control. The degradation wti this reached > 60 % after 6 days.

In the toxicity control (test item plus reference substance) the biodegradation came to a maximum of 40% after days. The biodegradation of the reference substance seemd not to be inhibited by the test item.