p,p',p''-tris(dimethylamino)trityl alcohol

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:

2 (reliable with restrictions)

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)

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

other: Polyseed capsule (broad spectrum bacteria)

Details on inoculum:

Polyseed capsule was used as inoculum in the study. Polyseed capsule is a blend of broad spectrum bacteria designed specifically as seed inoculums for the BOD test.
- Laboratory culture and Method of cultivation: 38.4 mg of polyseed from the capsule was weighed and added in 100 mL mineral media and then stirred for 1 h. This gave the bacterial count as 10E4 to 10E6 CFU/L. A further concentration of 1 mL/L of polyseed solution is prepared and from this working inoculum 0.125 mL solution is added to every bottles of 125 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):

42 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: detailed in additional information
- Solubilising agent (type and concentration if used): 2% DMSO
- Test temperature: 20±1°C
- pH:
At 0 hr = Blank control: 7.4, test chemical: 7.4; Procedure control: 7.4; Toxicity control: 7.4
- pH adjusted: No
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: BOD bottles (125 ml)
- Number of culture flasks/concentration: 2 flasks/ conentrations
- Measuring equipment: DO meter
- Test performed in closed vessels due to significant volatility of test substance: Not applicable, the BOD bottles were closed tightly with the stopper ensuring that no air bubbles are enclosed and then sealed with parafilm.

SAMPLING
- Sampling frequency: Sampling of all test vessels from each test group concentration were collected for analysis at zero-time (immediately after set-up), 7th, 14th, 21st, 28th, 39th and 42nd day during the incubation period.
- Sampling method: Oxygen consumption was measured directly by inserting oxygen probe in BOD bottles
- Sample storage before analysis: samples were analysed immediately after sampling

CONTROL AND BLANK SYSTEM
- Inoculum blank: Containing inoculum and mineral media;
- Solvent control: Containing mineral media with 2% DMSO and inoculum
- Toxicity control: Containing reference chemical (sodium benzoate) N-ATU, inoculum and mineral media
- Procedure control: Containing test chemical, reference compound (sodium benzoate), inoculum and mineral media

Reference substance:

benzoic acid, sodium salt

Key result

Parameter:

% degradation (O2 consumption)

Value:

30.48

Sampling time:

42 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 are reported in Tables 2 and 3, respectively. The BOD42 value of test chemical was observed to be 0.75 mgO2/mg. ThOD was determined by calculation as 2.46 mgO2/mg. % degradation was calculated using the values of BOD and ThOD for test chemical and was determined to be 30.48% at 20 ± 1°C. The % degradation of procedure control (reference item) was also calculated using BOD & ThOD and was determined to be 73.65%. Degradation of Sodium Benzoate exceeds 52.69% on 7 days & 61.67% on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid.

Results with reference substance:

The % degradation of procedure control (reference item) was also calculated using BOD & ThOD and was determined to be 73.65%. Degradation of Sodium Benzoate exceeds 52.69% on 7 days & 61.67% on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid.

TABLE:

D.O VALUES (mg/L)

No. of Days	Blank Control	Solvent Blank DO mg/L	Test Chemical	Procedure Control(Reference Chemical)	Toxicity Control
0	7.2	7.3	7.6	7.2	7.8
7	7	6.9	6.4	3.3	6.9
14	6.8	6.5	5.9	2.3	3.3
21	6.5	6.3	4.4	1.6	4
28	6.2	5.8	3.7	0.7	3.1
39	5.8	5.6	3.2	0.6	2.8
42	5.5	5.5	2.8	0.5	2.3

 

TABLE:

BOD VALUES (mgO₂/mg)

No. of Days	Test Chemical	Procedure Control(Reference Chemical)	Toxicity Control
0	0	0	0
7	0.20	0.88	0.12
14	0.23	1.03	0.93
21	0.55	1.15	0.70
28	0.60	1.25	0.80
39	0.68	1.23	0.83
42	0.75	1.23	0.93

 

TABLE:

% BIODEGRADATION

No. of Days	Test Chemical	Procedure Control(Reference Chemical)	Toxicity Control
0	0	0	0
7	8.13	52.69	5.28
14	9.34	61.67	37.80
21	22.35	68.86	28.45
28	24.39	74.85	32.52
39	27.64	73.65	33.73
42	30.48	73.65	37.80

 

TABLE:

BOD42, ThOD AND % BIODEGRADATION VALUES

Test System	BOD42	ThOD (mgO2/mg)	% Biodegradation
Test Chemical	0.75	2.46	30.48
Procedure Control(Reference Chemical)	1.23	1.67	73.65
Toxicity Control	0.93	2.46	37.80

 

TABLE:

pH VALUES

No. of Days	Blank Control	Solvent Blank pH	Test Chemical	Procedure Control(Reference Chemical)	Toxicity Control
0	7.4	7.4	7.4	7.4	7.4
7	7.2	7.1	7.2	7.1	7.3
14	7.1	7	7	7	7
21	7	7	7	7	7
28	6.9	6.8	6.9	6.9	7.0
39	6.9	6.9	6.9	6.9	7
42	6.9	6.8	6.9	6.9	6.9

Validity criteria fulfilled:

yes

Interpretation of results:

inherently biodegradable

Conclusions:

The test chemical undergoes 30.48% biodegradation after 42 days in the test condition. Thus, the test chemical was considered to be inherently biodegradable.

Executive summary:

Biodegradation study was conducted for 28-days Closed Bottle test following the OECD guideline 301 D for determining the ready biodegradability of the test chemical. Polyseed capsule ( blend of broad spectrum bacteria) designed specifically as seed inoculums for the BOD test. 38.4 mg of polyseed from the capsule was weighed and added in 100 mL mineral media and then stirred for 1 h. This gave the bacterial count as 10E4 to 10E6 CFU/L. A further concentration of 1 mL/L of polyseed solution is prepared and from this working inoculum 0.125 mL solution is added to every bottles of 125 mL. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism.125 mL BOD vessels were used in the study. The test system includes an inoculum blank control group, solvent control, a procedure control group, and a test item group, a toxicity control group, each maintained in replicates. The biodegradation was determined by following the BOD, oxygen consumption of the test item in the incubation BOD vessels during exposure. Sodium benzoate was tested simultaneously under the same conditions as the test item, and functioned as a procedure control. All test vessels were incubated at BOD incubator at a constant temperature of 20±1° C. Sampling of 0^th h test vessels from each test group concentration were collected for analysis at zero-time (immediately after set-up). Samples were removed at regular intervals i.e., 7th, 14th, 21st, 28th, 39th and 42nd day during the incubation period which were measured for D.O and pH also. The theoretical oxygen demand (ThOD) was calculated based on the chemical identifier. The % degradation of procedure control (reference item) was also calculated using BOD & ThOD and was determined to be 73.65%. Degradation of Sodium Benzoate exceeds 52.69% on 7 days & 61.67% on 14th day, thus confirming the suitability of the used activated sludge inoculum. In the toxicity control containing both, the test item and the procedure control sodium benzoate, 37.8% biodegradation was noted after 42 days of incubation. Thus, the test item can be assumed to be not inhibitory to the activated sludge microorganisms. Under the test conditions the percentage biodegradation of test chemical reached 30.48% after 42 days of incubation based on BOD consumption. As the final biodegradation is less than 70% in this test and all validity criteria were met, test item was considered to be inherently biodegradablein water.

Description of key information

Biodegradation study was conducted for 28-days Closed Bottle test following the OECD guideline 301 D for determining the ready biodegradability of the test chemical. Polyseed capsule ( blend of broad spectrum bacteria) designed specifically as seed inoculums for the BOD test. 38.4 mg of polyseed from the capsule was weighed and added in 100 mL mineral media and then stirred for 1 h. This gave the bacterial count as 10E4 to 10E6 CFU/L. A further concentration of 1 mL/L of polyseed solution is prepared and from this working inoculum 0.125 mL solution is added to every bottles of 125 mL. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism.125 mL BOD vessels were used in the study. The test system includes an inoculum blank control group, solvent control, a procedure control group, and a test item group, a toxicity control group, each maintained in replicates. The biodegradation was determined by following the BOD, oxygen consumption of the test item in the incubation BOD vessels during exposure. Sodium benzoate was tested simultaneously under the same conditions as the test item, and functioned as a procedure control. All test vessels were incubated at BOD incubator at a constant temperature of 20±1° C. Sampling of 0^th h test vessels from each test group concentration were collected for analysis at zero-time (immediately after set-up). Samples were removed at regular intervals i.e., 7th, 14th, 21st, 28th, 39th and 42nd day during the incubation period which were measured for D.O and pH also. The theoretical oxygen demand (ThOD) was calculated based on the chemical identifier. The % degradation of procedure control (reference item) was also calculated using BOD & ThOD and was determined to be 73.65%. Degradation of Sodium Benzoate exceeds 52.69% on 7 days & 61.67% on 14th day, thus confirming the suitability of the used activated sludge inoculum. In the toxicity control containing both, the test item and the procedure control sodium benzoate, 37.8% biodegradation was noted after 42 days of incubation. Thus, the test item can be assumed to be not inhibitory to the activated sludge microorganisms. Under the test conditions the percentage biodegradation of test chemical reached 30.48% after 42 days of incubation based on BOD consumption. As the final biodegradation is less than 70% in this test and all validity criteria were met, test item was considered to be inherently biodegradablein water.

Key value for chemical safety assessment

Biodegradation in water:

inherently biodegradable

Additional information

Biodegradation study was conducted for 28-days Closed Bottle test following the OECD guideline 301 D for determining the ready biodegradability of the test chemical. Polyseed capsule ( blend of broad spectrum bacteria) designed specifically as seed inoculums for the BOD test. 38.4 mg of polyseed from the capsule was weighed and added in 100 mL mineral media and then stirred for 1 h. This gave the bacterial count as 10E4 to 10E6 CFU/L. A further concentration of 1 mL/L of polyseed solution is prepared and from this working inoculum 0.125 mL solution is added to every bottles of 125 mL. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism.125 mL BOD vessels were used in the study. The test system includes an inoculum blank control group, solvent control, a procedure control group, and a test item group, a toxicity control group, each maintained in replicates. The biodegradation was determined by following the BOD, oxygen consumption of the test item in the incubation BOD vessels during exposure. Sodium benzoate was tested simultaneously under the same conditions as the test item, and functioned as a procedure control. All test vessels were incubated at BOD incubator at a constant temperature of 20±1° C. Sampling of 0^th h test vessels from each test group concentration were collected for analysis at zero-time (immediately after set-up). Samples were removed at regular intervals i.e., 7th, 14th, 21st, 28th, 39th and 42nd day during the incubation period which were measured for D.O and pH also. The theoretical oxygen demand (ThOD) was calculated based on the chemical identifier. The % degradation of procedure control (reference item) was also calculated using BOD & ThOD and was determined to be 73.65%. Degradation of Sodium Benzoate exceeds 52.69% on 7 days & 61.67% on 14th day, thus confirming the suitability of the used activated sludge inoculum. In the toxicity control containing both, the test item and the procedure control sodium benzoate, 37.8% biodegradation was noted after 42 days of incubation. Thus, the test item can be assumed to be not inhibitory to the activated sludge microorganisms. Under the test conditions the percentage biodegradation of test chemical reached 30.48% after 42 days of incubation based on BOD consumption. As the final biodegradation is less than 70% in this test and all validity criteria were met, test item was considered to be inherently biodegradablein water.