Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Biodegradation in water

35-days Closed Bottle test following the OECD guideline 301 D to determine the ready biodegradability of the test item (Experimental study report, 2018). The study was performed at a temperature of 20°C. The test system included control, test item and reference item. Polyseed were used for this study. 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 73.49 %. Degradation of Sodium Benzoate exceeds 39.15 % on 7 days & 70.48 % on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid. The BOD35 value of test chemical was observed to be 1.17 mgO2/mg. ThOD was calculated as 2.47 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 47.36 %. Based on the results, the test item under the test conditions, was considered to be Ultimate inherent biodegradable in nature.

 

Biodegradation in water and sediment

Estimation Programs Interface (2017) prediction model was run to predict the half-life in water and sediment for the test chemical. If released in to the environment, 21.9% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of test chemical in water is estimated to be 15 days (360 hrs). The half-life (15 days estimated by EPI suite) indicates that the test chemical is not persistent in water and the exposure risk to aquatic animals is moderate to low whereas the half-life period of test chemical in sediment is estimated to be 135 days (3240 hrs) but since the diffussion in the medium is less than 5% (reported as 3.09%), the substance is considered to be not persistent in sediment.

 

Biodegradation in soil

The half-life period of test chemical in soil was estimated using Level III Fugacity Model by EPI Suite version 4.1 estimation database (EPI suite, 2017). If released into the environment, 73.4 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical in soil is estimated to be 30 days (720 hrs). Based on this half-life value of test chemical, it is concluded that the test chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is moderate to low.

Additional information

Biodegradation in water

35-days Closed Bottle test following the OECD guideline 301 D to determine the ready biodegradability of the test item (Experimental study report, 2018). The study was performed at a temperature of 20°C. The test system included control, test item and reference item. Polyseed were used for this study. 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 73.49 %. Degradation of Sodium Benzoate exceeds 39.15 % on 7 days & 70.48 % on 14th day. The activity of the inoculum is thus verified and the test can be considered as valid. The BOD35 value of test chemical was observed to be 1.17 mgO2/mg. ThOD was calculated as 2.47 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 47.36 %. Based on the results, the test item under the test conditions, was considered to be Ultimate inherent biodegradable in nature.

 

Biodegradation in water and sediment

Estimation Programs Interface (2017) prediction model was run to predict the half-life in water and sediment for the test chemical. If released in to the environment, 21.9% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of test chemical in water is estimated to be 15 days (360 hrs). The half-life (15 days estimated by EPI suite) indicates that the test chemical is not persistent in water and the exposure risk to aquatic animals is moderate to low whereas the half-life period of test chemical in sediment is estimated to be 135 days (3240 hrs) but since the diffussion in the medium is less than 5% (reported as 3.09%), the substance is considered to be not persistent in sediment.

Biodegradation in soil

The half-life period of test chemical in soil was estimated using Level III Fugacity Model by EPI Suite version 4.1 estimation database (EPI suite, 2017). If released into the environment, 73.4 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical in soil is estimated to be 30 days (720 hrs). Based on this half-life value of test chemical, it is concluded that the test chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is moderate to low.

On the basis of above results for test chemical, it can be concluded that the test chemical can be expected to be ultimate inherently biodegradable in nature.