3-methoxyacetophenone

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 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 this study. 1 polyseed capsule were added in 500 ml D.I water and then stirred for 1 hour
for proper mixing and functioning of inoculum. This gave the bacterial count as 107 to 108 CFU/ml. At the regular interval microbial plating was
also performed on agar to confirm the vitalityand 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: 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

Parameter:

% degradation (O2 consumption)

Value:

47.08

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 1.05 mgO2/mg. ThOD was determined by calculation as 2.23 mgO2/mg. % degradation was calculated using the values of BOD and ThOD for test item and was determined to be 47.08% at 20 ± 1°C. The % degradation of procedure control (reference item) was also calculated using BOD & ThOD and was determined to be 75.3 %. Degradation of Sodium Benzoate exceeds 43.37% on 7 days & 61.44 % 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 75.3 %. Degradation of Sodium Benzoate exceeds 43.37% on 7 days & 61.44% on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid.

Table 1:D.O Values(mg/L)

No. of Days Inoculum Blank	(Control)	Test Suspension Procedure Control	(Reference Item)
0	6.8	6.6	6.5
7	6.6	5.7	3.4
14	6.5	5	2.1
21	6.2	4.4	1.8
28	6	1.6	0.5
35	5.8	1.5	0.4
42	5.6	1.19	0.3

 

Table 2: BOD values (mgO2/mg)

No. of Days	Test Suspension Procedure Control	(Reference Item)
0	0	0
7	0.17	0.72
14	0.32	1.02
21	0.4	7
28	1.05	1.3
35	1.02	1.27
42	1.05	1.25

 

 

Table 3: PERCENT BIODEGRDATION RESULTS

No. of Days	Test Suspension Procedure Control	(Reference Item)
0	0%	0%
7	7.62%	43.37%
14	14.57%	61.44%
21	17.93%	61.44%
28	47.08%	78.31%
35	45.73%	76.5%
42	47.08%	75.3%
	%	%

 

Table 4: BOD42, THOD AND % BIODEGRADATION VALUES

Method details	BOD35 (mgO2/mg)	ThOD (mgO2/mg)	% Biodegradation
Test Item	1.05	2.23	47.08
Reference Item	1.25	1.66	75.3

Validity criteria fulfilled:

yes

Interpretation of results:

other: ultimate inherently biodegradable

Conclusions:

The test item 3-methoxyacetophenone (CAS no. 586-37-8) undergoes 47.08 % biodegradation after 42 days in the test condition. Thus, the test item was considered to be ultimate inherently biodegradable.

Executive summary:

42-days Closed Bottle test following the OECD guideline 301 D to determine the ready biodegradability of the test item. The study was performed at a temperature of 20°C. The test system included control, test item and reference item.Polyseed were used as inoculums at concentration of bacterial count as 10E7 to 10E8 CFU/ml.

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. OECD mineral medium was used for the study. 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 (reference item) was also calculated using BOD & ThOD and was determined to be 75.3%. Degradation of Sodium Benzoate exceeds 43.37% on 7 days & 61.44% on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid. The BOD42 value of test chemical was observed to be 1.05 mgO2/mg. ThOD was calculated as 2.23 mgO2/mg. Accordingly, the % degradation of the test item after 42 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 47.08%. Based on the results, 3 -methoxyacetophenone, under the test conditions, was considered to be ultimate inherently biodegradable in nature.

Description of key information

The % degradation of the test item after 42 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 47.08%. Based on the results, 3 -methoxyacetophenone, under the test conditions, was considered to be ultimate inherently biodegradable in nature.

Key value for chemical safety assessment

Biodegradation in water:

inherently biodegradable

Additional information

42-days Closed Bottle test following the OECD guideline 301 D to determine the ready biodegradability of the test item. The study was performed at a temperature of 20°C. The test system included control, test item and reference item.Polyseed were used as inoculums at concentration of bacterial count as 10E7 to 10E8 CFU/ml.

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. OECD mineral medium was used for the study. 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 (reference item) was also calculated using BOD & ThOD and was determined to be 75.3%. Degradation of Sodium Benzoate exceeds 43.37% on 7 days & 61.44% on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid. The BOD42 value of test chemical was observed to be 1.05 mgO2/mg. ThOD was calculated as 2.23 mgO2/mg. Accordingly, the % degradation of the test item after 42 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 47.08%. Based on the results, 3 -methoxyacetophenone, under the test conditions, was considered to be ultimate inherently biodegradable in nature.