Phenethyl phenylacetate

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)

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 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):

28 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Parameter followed for biodegradation estimation:

other: 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:

benzoic acid, sodium salt

Key result

Parameter:

other: % degradation (O2 consumption) and ThOD

Value:

32.17

Sampling time:

28 d

Remarks on result:

other: Other details not known

Details on results:

The DO depletion (oxygen consumed mg O2/l), BOD and percent biodegradation results for each test system are reported. The DO depletion by the test systems was corrected for DO depletion occurring in the blank test systems. The DO depletion in the inoculum blank (control) at the end of test duration was determined to be 19.1 mgO2/l. The BOD28 value of test chemical was observed to be 0.814 mgO2/mg. ThoD was determined by calculation as 2.53 mgO2/mg. % Degradation was calculated using the values of BOD and ThOD for test substance. Accordingly, the % degradation of the test substance after 28 days of incubation at 20°C according to manometric respirometry test was determined to be 32.17%. The % degradation of procedure control (reference substance) was also calculated using BOD & ThOD and was determined to be 227.4%. The DO depletion (mg O2/l) in control on 28th day is 19.1 mg O2/l which fullfills the control validity criteria (i.e., The DO depletion 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 acetate exceeds 168.29% after 7 days and 212.76 % after 14 days. The activity of the inoculum is thus verified and the test is considered as valid.

Results with reference substance:

The % degradation of procedure control (reference substance) was also calculated using BOD & ThOD and was determined to be 227.4%. The DO depletion (mg O2/l) in control on 28th day is 19.1 mg O2/l which fullfills the control validity criteria (i.e., The DO depletion 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 acetate exceeds 168.29% after 7 days and 212.76 % after 14 days. The activity of the inoculum is thus verified and the test is considered as valid.

Table 1: BOD₂₈, Calculated ThOD and % Biodegradation Values

Method details	BOD28(mgO2/mg)	ThOD (mgO2/mg)	% Biodegradation
Test Substance	0.813 mg O2/mg	2.53 mg O2/mg	32.17 %
Reference Substance	1.069 mg O2/mg	0.470 mg O2/mg	227.4 %

Validity criteria fulfilled:

yes

Interpretation of results:

other: Inherently biodegradable

Conclusions:

The test chemical undergoes 32.17 % biodegradation at 20 ± 1°C after 28 days in the test condition. Thus, the test chemical can be considered as inherently biodegradable.

Executive summary:

28-days Manometric respirometry test following the OECD guideline 301F was conducted to determine the ready biodegradability of the test chemical. 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. 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 was 100 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 (reference substance) was also calculated using BOD & ThOD and was determined to be 227.4%. The DO depletion (mg O2/l) in control on 28th day is 19.1 mg O2/l which fullfills the control validity criteria (i.e., The DO depletion 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 acetate exceeds 168.29% after 7 days and 212.76 % after 14 days. The activity of the inoculum is thus verified and the test is considered as valid. The BOD28 value of test chemical was observed to be 0.814 mgO2/mg. ThOD was calculated as 2.53 mgO2/mg. Accordingly, the % degradation of the test chemical after 28 days of incubation at 20 ± 1°C according to manometric respirometry test was determined to be 32.17%. Based on the results, the test chemical was considered to be inherently 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 was conducted to determine the ready biodegradability of the test chemical. 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. 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 was 100 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 (reference substance) was also calculated using BOD & ThOD and was determined to be 227.4%. The DO depletion (mg O2/l) in control on 28th day is 19.1 mg O2/l which fulfills the control validity criteria (i.e., The DO depletion 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 acetate exceeds 168.29% after 7 days and 212.76 % after 14 days. The activity of the inoculum is thus verified and the test is considered as valid. The BOD28 value of test chemical was observed to be 0.814 mgO2/mg. ThOD was calculated as 2.53 mgO2/mg. Accordingly, the % degradation of the test chemical after 28 days of incubation at 20 ± 1°C according to manometric respirometry test was determined to be 32.17%. Based on the results, the test chemical was considered to be inherently biodegradable at 20 ± 1°C over a period of 28 days. 

 

Key value for chemical safety assessment

Biodegradation in water:

inherently biodegradable

Type of water:

freshwater

Additional information

28-days Manometric respirometry test following the OECD guideline 301F was conducted to determine the ready biodegradability of the test chemical. 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. 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 was 100 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 (reference substance) was also calculated using BOD & ThOD and was determined to be 227.4%. The DO depletion (mg O2/l) in control on 28th day is 19.1 mg O2/l which fulfills the control validity criteria (i.e., The DO depletion 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 acetate exceeds 168.29% after 7 days and 212.76 % after 14 days. The activity of the inoculum is thus verified and the test is considered as valid. The BOD28 value of test chemical was observed to be 0.814 mgO2/mg. ThOD was calculated as 2.53 mgO2/mg. Accordingly, the % degradation of the test chemical after 28 days of incubation at 20 ± 1°C according to manometric respirometry test was determined to be 32.17%. Based on the results, the test chemical was considered to be inherently biodegradable at 20 ± 1°C over a period of 28 days.