2-(3,6-dihydroxy-2,4,5,7-tetraiodoxanthen-9-yl)benzoic acid, aluminium salt

Biodegradation in water: screening tests

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 F (Ready Biodegradability: Manometric Respirometry Test)

Principles of method if other than guideline:

Biodegradation study was conducted according to OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test) for evaluating the percentage biodegradability of test chemical.

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

other: mixture of domestic waste water, surface soil and soil samples

Details on inoculum:

Mixed Inoculum Preparation (In-House): Domestic waste water, surface soil and soil samples from polluted sites receiving predominantly domestic waste was collected and were mixed to get diluted suspension. The inoculum was kept aerobic until being used for experiment by supplying organic and inorganic sources required by micro flora to sustain at controlled laboratory conditions. This gave the bacterial count as 107to 108 CFU/ml. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism.

Parameter followed for biodegradation estimation:

other: BOD and ThOD

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 Respirometer BOD Sensor System (Code: F102B0133; non-automatic pressure measurement sensor system) and Respirometric incubator (FOC 120i)) by VELP Scientifica.

CONTROL AND BLANK SYSTEM
- Inoculum blank: it contains only test inoculum
- Procedure control: contains reference compound and inoculum

Reference substance:

other: Sodium Benzoate

Parameter:

other: BOD and ThOD

Value:

6.126

Sampling time:

28 d

Remarks on result:

other: Other details not known

Details on results:

The oxygen consumed by the test systems wascorrected 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 2-(3,6-dihydroxy-2,4,5,7-tetraiodoxanthen-9-yl)benzoic acid, aluminium salt(CAS No. 12227-78-0) was observed to be 0.04 mgO2/mg. ThoD was determined by calculation as 0.653 mgO2/mg. % Degradation was calculated using the values of BOD and ThOD for test item and was found to be 6.126%. The % degradation of procedure control (Sodium Benzoate) was also calculated using BOD & ThOD and was found to be 74.074%. The mean BOD values(mg O2/l) in control on 28th day was 9mg O2/l, thereby fulfilling the control validity criteria (i.e., The oxygen consumption of the inoculum blank is normally 20-30 mg O2/l and should not be greater than 60 mg/l in 28 days). Degradation of Sodium Benzoate exceeds 50.050%after 7 days and 68.068% after 14 days. The activity of the inoculums is thus verified and the test can be considered as valid.

Results with reference substance:

The % degradation of procedure control (Sodium Benzoate) was also calculated using BOD & ThOD and was found to be 74.074%. The mean BOD values (mg O2/l) in control on 28th day was 9 mg O2/l, thereby fulfilling the control validity criteria (i.e., The oxygen consumption of the inoculum blank is normally 20-30 mg O2/l and should not be greater than 60 mg/l in 28 days). Degradation of Sodium Benzoate exceeds 50.050 %after 7 days and 68.068 % after 14 days. The activity of the inoculums is thus verified and the test can be considered as valid.

TABLE 1

RESPIROMETRIC VALUES(oxygen consumed mg O2/l)

No. of Days	Inoculum Blank (Control)	Test Suspension	Procedure Control (Reference Item)
1	4	4	12
2	6	6	18
3	7	6	23
4	9	7	28
5	9	7	29
6	7	3	29
7	7	6	31
8	9	4	32
9	7	4	32
10	0	0	0
11	9	3	34
12	9	6	37
13	7	7	40
14	7	7	40
15	7	7	41
16	7	9	42
17	9	9	43
18	9	9	45
19	9	10	45
20	9	10	46
21	9	10	46
22	7	9	46
23	9	9	45
24	9	10	45
25	9	10	46
26	9	10	46
27	9	10	46
28	9	10	46

 

 

TABLE 2

BOD values (mgO2/mg)

No. of Days	Test Suspension	Procedure Control (Reference Item)
1	0	0.267
2	0	0.4
3	-0.04	0.533
4	-0.08	0.633
5	-0.08	0.667
6	-0.16	0.733
7	-0.04	0.8
8	-0.2	0.767
9	-0.12	0.833
10	0	0
11	-0.24	0.833
12	-0.12	0.933
13	0	1.1
14	0	1.1
15	0	1.133
16	0.08	1.167
17	0	1.133
18	0	1.2
19	0.04	1.2
20	0.04	1.233
21	0.04	1.233
22	0.08	1.3
23	0	1.2
24	0.04	1.2
25	0.04	1.233
26	0.04	1.233
27	0.04	1.233
28	0.04	1.233

 

 

TABLE 3

PERCENT BIODEGRDATION RESULTS

No. of Days	Test Suspension	Procedure Control (Reference Item)
1	0	16.016
2	0	24.024
3	-6.126	32.032
4	-12.251	38.038
5	-12.251	40.04
6	-24.502	44.044
7	-6.126	48.048
8	-30.628	46.046
9	-18.377	50.05
10	0	0
11	-36.753	50.05
12	-18.377	56.056
13	0	66.066
14	0	66.066
15	0	68.068
16	12.251	70.07
17	0	68.068
18	0	72.072
19	6.126	72.072
20	6.126	74.074
21	6.126	74.074
22	12.251	78.078
23	0	72.072
24	6.126	72.072
25	6.126	74.074
26	6.126	74.074
27	6.126	74.074
28	6.126	74.074

 

 

Table 4

BOD28, THOD AND % BIODEGRADATION VALUES

Method details	BOD28 (mgO2/mg)	ThOD (mgO2/mg)	% Biodegradation	pH 0th Day	pH 28th Day
Test Item	0.04	0.653	6.126	7.5	7.85
Reference Item	1.233	1.665	74.074	7.0	7.64

Validity criteria fulfilled:

yes

Interpretation of results:

other: readily / not readily / inherently biodegradable

Conclusions:

The test item 2-(3,6-dihydroxy-2,4,5,7-tetraiodoxanthen-9-yl)benzoic acid, aluminium salt(CAS No. 12227-78-0) undergoes 6.126 % biodegradation after 28 days in the test condition. Thus, the test item can be inferred/considered as non-biodegradable.

Executive summary:

28-days Manometric respirometry test following the OECD guideline 301F to determine the ready biodegradability of the test chemical 2-(3,6-dihydroxy-2,4,5,7-tetraiodoxanthen-9-yl)benzoic acid, aluminium salt(CAS No. 12227-78-0). The study was performed at a temperature of 20± 1°C. Mixture of domestic waste water, surface soil and soil samples was used as a test inoculum for the study. This inoculum was collected and were mixed to get diluted suspension. The inoculum was kept aerobic until being used for experiment by supplying organic and inorganic sources required by micro flora to sustain at controlled laboratory conditions.  This gave the bacterial count as 107to 108 CFU/ml. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism. OECD mineral medium was used for the study. The test system included control, test item and reference item. The concentration of test and reference item ( Sodium Benzoate) chosen for both the study was30 mg/L, while that of inoculum was 10 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 % degradation of procedure control (Sodium Benzoate) was also calculated using BOD & ThOD and was determined to be 74.074%. The mean BOD values (mg O2/l) in control on 28th day was 9 mg O2/l, thereby fulfilling the control validity criteria (i.e., The oxygen consumption of the inoculum blank is normally 20-30 mg O2/l and should not be greater than 60 mg/l in 28 days). Degradation of Sodium Benzoate exceeds 50.050 %after 7 days and 68.068 % after 14 days. The activity of the inoculums is thus verified and the test can be considered as valid. The BOD28 value of test chemical 2-(3,6-dihydroxy-2,4,5,7-tetraiodoxanthen-9-yl)benzoic acid, aluminium salt, CAS No. 12227-78-0 was observed to be 0.04 mgO2sup>/mg. ThOD was calculated as 0.653 mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to manometric respirometry test was determined to be 6.126%.Based on the results, the test item, under the test conditions, was considered to be not biodegradable at 20 ± 1°C over a period of 28 days.

Description of key information

28-days Manometric respirometry test following the OECD guideline 301F to determine the ready biodegradability of the test chemical 2-(3,6-dihydroxy-2,4,5,7-tetraiodoxanthen-9-yl)benzoic acid, aluminium salt(CAS No. 12227-78-0). The study was performed at a temperature of 20± 1°C. Mixture of domestic waste water, surface soil and soil samples was used as a test inoculum for the study. This inoculum was collected and were mixed to get diluted suspension. The inoculum was kept aerobic until being used for experiment by supplying organic and inorganic sources required by micro flora to sustain at controlled laboratory conditions.  This gave the bacterial count as 107to 108 CFU/ml. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism. OECD mineral medium was used for the study. The test system included control, test item and reference item. The concentration of test and reference item ( Sodium Benzoate) chosen for both the study was30 mg/L, while that of inoculum was 10 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 % degradation of procedure control (Sodium Benzoate) was also calculated using BOD & ThOD and was determined to be 74.074%. The mean BOD values (mg O2/l) in control on 28th day was 9 mg O2/l, thereby fulfilling the control validity criteria (i.e., The oxygen consumption of the inoculum blank is normally 20-30 mg O2/l and should not be greater than 60 mg/l in 28 days). Degradation of Sodium Benzoate exceeds 50.050 %after 7 days and 68.068 % after 14 days. The activity of the inoculums is thus verified and the test can be considered as valid. The BOD28 value of test chemical 2-(3,6-dihydroxy-2,4,5,7-tetraiodoxanthen-9-yl)benzoic acid, aluminium salt, CAS No. 12227-78-0 was observed to be 0.04 mgO2sup>/mg. ThOD was calculated as 0.653 mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to manometric respirometry test was determined to be 6.126%.Based on the results, the test item, under the test conditions, was considered to be not biodegradable at 20 ± 1°C over a period of 28 days.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

28-days Manometric respirometry test following the OECD guideline 301F to determine the ready biodegradability of the test chemical 2-(3,6-dihydroxy-2,4,5,7-tetraiodoxanthen-9-yl)benzoic acid, aluminium salt(CAS No. 12227-78-0). The study was performed at a temperature of 20± 1°C. Mixture of domestic waste water, surface soil and soil samples was used as a test inoculum for the study. This inoculum was collected and were mixed to get diluted suspension. The inoculum was kept aerobic until being used for experiment by supplying organic and inorganic sources required by micro flora to sustain at controlled laboratory conditions.  This gave the bacterial count as 107to 108 CFU/ml. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism. OECD mineral medium was used for the study. The test system included control, test item and reference item. The concentration of test and reference item ( Sodium Benzoate) chosen for both the study was30 mg/L, while that of inoculum was 10 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 % degradation of procedure control (Sodium Benzoate) was also calculated using BOD & ThOD and was determined to be 74.074%. The mean BOD values (mg O2/l) in control on 28th day was 9 mg O2/l, thereby fulfilling the control validity criteria (i.e., The oxygen consumption of the inoculum blank is normally 20-30 mg O2/l and should not be greater than 60 mg/l in 28 days). Degradation of Sodium Benzoate exceeds 50.050 %after 7 days and 68.068 % after 14 days. The activity of the inoculums is thus verified and the test can be considered as valid. The BOD28 value of test chemical 2-(3,6-dihydroxy-2,4,5,7-tetraiodoxanthen-9-yl)benzoic acid, aluminium salt, CAS No. 12227-78-0 was observed to be 0.04 mgO2sup>/mg. ThOD was calculated as 0.653 mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to manometric respirometry test was determined to be 6.126%.Based on the results, the test item, under the test conditions, was considered to be not biodegradable at 20 ± 1°C over a period of 28 days.