Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
Experimental result using OECD guidelines.
Qualifier:
according to guideline
Guideline:
OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)
Principles of method if other than guideline:
Biodegradation study was conducted according to OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test) for evaluating the percentage biodegradability of test substance
GLP compliance:
no
Oxygen conditions:
not specified
Inoculum or test system:
other: Mixed inoculum
Details on inoculum:
Mixed Inoculum Preparation: Polyseed were used for mixed inoculum. One capsule of Polyseed were added in 500 ml of DI water to make up the solution. Afterwards 1 hour of stirring were given for proper mixing of mixed inoculum. This gave the bacterial count as 10E7 to 10E8 CFU/ml. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism.
Duration of test (contact time):
35 d
Initial conc.:
4 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation:
O2 consumption
Details on study design:
TEST CONDITIONS
- Composition of medium: OECD mineral medium was used for the study
- Test temperature: 20°C
- Continuous darkness: Yes
- Other: The water used in this study is deionized water.

TEST SYSTEM
- Culturing apparatus: The apparatus used in this study is BOD bottles; with glass stoppers (125 ml), BOD incubator & oxygen electrode and meter.

CONTROL AND BLANK SYSTEM
- Inoculum blank: it contains only test inoculum
- Procedure control: contains reference compound and inoculum
Reference substance:
other: Sodium Benzoate
Key result
Parameter:
% degradation (O2 consumption)
Value:
33.07
Sampling time:
28 d
Remarks on result:
other: Other details not known
Details on results:
The oxygen consumed by the test systems was corrected for oxygen consumption occurring in the blank test systems.The BOD Values (mgO2/mg) and percent biodegradation results for each test system arereported in Tables 2 and 3, respectively. The BOD28 value of test chemical was observed to be 0.87mgO2/mg. ThOD was determined by calculation as 2.63 mgO2/mg. % Degradation was calculated using the values of BOD and ThOD for test item and was found to be 33.07% at 20 ± 1°C. The % degradation of procedure control (reference item) was also calculated using the values of BOD & ThOD and was found to be 73.49% at 20 ± 1°C. Degradation of Sodium Benzoate exceeds 31.32% on 7 days & 49.39 % on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid.
Results with reference substance:
Degradation of Sodium Benzoate exceeds 31.32% on 7 days & 49.39% on 14th day. The % degradation of procedure control (reference item) was also calculated using the values of BOD & ThOD and was found to be 73.49 % at 20 ± 1°C.

TABLE 1

D.O Values(mg/L)

No. of Days

Inoculum Blank

(Control)

 

Test Suspension

Procedure Control

(Reference Item)

 

0

6.6

6.6

6.6

7

6

4.4

3.9

14

5.8

4

2.5

21

5.7

3.7

1.2

28

5.6

3.2

0.7

35

5.4

1.9

0.5

 

TABLE 2

BOD values (mgO2/mg)

No. of Days

Test Suspension

Procedure Control

(Reference Item)

 

0

0

0

7

0.37

0.52

14

0.45

0.82

21

0.5

1.12

28

0.6

1.22

35

0.87

1.22

 

TABLE 3

PERCENT BIODEGRDATION RESULTS

No. of Days

Test Suspension

Procedure Control

(Reference Item)

 

0

0%

0%

7

14.06%

31.32%

14

17.11%

49.39%

21

19.01%

67.46%

28

22.81%

73.49%

35

33.07%

73.49%

 

Table 4

BOD35, THOD AND % BIODEGRADATION VALUES

Method details

BOD35 (mgO2/mg)

ThOD (mgO2/mg)

% Biodegradation

 

TestItem

0.87

2.63

33.07

ReferenceItem

1.22

1.66

73.49

Validity criteria fulfilled:
yes
Interpretation of results:
inherently biodegradable, fulfilling specific criteria
Conclusions:
The test chemical undergoes 33.07 % biodegradation after 35 days in the test condition. Thus, the test chemical was considered to be primary inherently biodegradable in nature.
Executive summary:

35-days Closed Bottle test following the OECD guideline 301 D was performed to determine the ready biodegradability of the test chemical. The test system included control, test item and reference item. The concentration of test and reference item ( Sodium Benzoate) chosen for both the study was 4 mg/L, while that of inoculum was 32 ml/l. ThOD (Theoretical oxygen demand) of test and reference item was determined by calculation. % degradation was calculated using the values of BOD and ThOD for test item and reference item. The BOD35 value of test chemical was observed to be 0.87 mgO2/mg. ThOD was calculated as 2.63 mgO2/mg. Accordingly, the % degradation of the test item after 35 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 33.07 %. Based on the results, the test chemical, under the test conditions was considered to be primary inherently biodegradable at 20 ± 1°C over a period of 35 days.

Description of key information

35-days Closed Bottle test following the OECD guideline 301 D was performed to determine the ready biodegradability of the test chemical. The test system included control, test item and reference item. The concentration of test and reference item ( Sodium Benzoate) chosen for both the study was 4 mg/L, while that of inoculum was 32 ml/l. ThOD (Theoretical oxygen demand) of test and reference item was determined by calculation. % degradation was calculated using the values of BOD and ThOD for test item and reference item. The BOD35 value of test chemical was observed to be 0.87 mgO2/mg. ThOD was calculated as 2.63 mgO2/mg. Accordingly, the % degradation of the test item after 35 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 33.07 %. Based on the results, the test chemical, under the test conditions was considered to be primary inherently biodegradable at 20 ± 1°C over a period of 35 days.

Key value for chemical safety assessment

Biodegradation in water:
inherently biodegradable

Additional information

35-days Closed Bottle test following the OECD guideline 301 D was performed to determine the ready biodegradability of the test chemical. The test system included control, test item and reference item. The concentration of test and reference item ( Sodium Benzoate) chosen for both the study was 4 mg/L, while that of inoculum was 32 ml/l. ThOD (Theoretical oxygen demand) of test and reference item was determined by calculation. % degradation was calculated using the values of BOD and ThOD for test item and reference item. The BOD 35 value of test chemical was observed to be 0.87 mgO2/mg. ThOD was calculated as 2.63 mgO2/mg. Accordingly, the % degradation of the test item after 35 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 33.07 %. Based on the results, the test chemical, under the test conditions was considered to be primary inherently biodegradable at 20 ± 1°C over a period of 35 days.