Benzyl butyrate

Endpoint summary

Description of key information

Stability:

Hydrolysis:

According to annex VIII column 2 of REACH regulation the study does not need to be conducted because the substance is readily biodegradable.

Biodegradation:

Biodegradation in water:

The Ready Biodegradability of test chemical was determined by the Manometric respirometry . The method used is basically the one described under No. 301 F in the  OECD Guidelines for Testing of Chemicals.

A measured volume of inoculated   mineral   medium,  containing a known concentration of test substance 30 mg/L as the nominal  sole source of organic carbon, is stirred in a closed flask at a constant  temperature (± 1 °C) for up to 28 days. Evolved carbon dioxide is absorbed in sodium hydroxide pellets. The consumption  of oxygen  is determined  bymeasuring  the pressure drop in the respirometer  flask. The Biological Oxygen Demand (BOD), amount of oxygen taken up by the microbial population during  biodegradation of the test chemical (corrected for uptake by blank inoculum, run in parallel)  is expressed as a percentage of ThOD (Theoretical Oxygen Demand, calculated from the elemental composition, assuming that carbon is oxidized to carbon dioxide,  hydrogen to water and nitrogen to ammonium, nitrite or nitrate).

Test chemical undergoes 88% biodegradation after 28 days (87%after 62 days) in the test conditions.The10-day window criterionis also fulfilled (20% biodegradation on day 1 and 77% on day11). Thus, test chemical should be regarded as readily biodegradable according to this test.

Test chemical did not inhibit the intrinsic respiration of the inoculum at the test concentration and was therefore considered to be non-toxic to the inoculum at the test concentration.

Biodegradation in water and sediments:

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test chemical. If released in to the environment, 24.8  % 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 chemical is not persistent in water and the exposure risk to aquatic animals is low whereas the half-life period of test chemical in sediment is estimated to be 135 days (3240  hrs). However, as the percentage release of test chemical into the sediment is less than 1% (i.e, reported as  0.406 %), indicates that test chemical is 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, 2018). If released into the environment, 72.6 % 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 chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is low.

Bioaccumulation:

Bioaccumulation: aquatic/sediments:

The estimated bio concentration factor (BCF) for tset chemical is 48.76 L/kg whole body w.w which does not exceed the bio concentration threshold of 2000. Thus it is concluded that test chemical is not expected to bioaccumulate in the food chain.

Transport and distribution:

Adsorption / desorption:

The adsorption coefficient Koc in soil and in sewage sludge of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals. The reference substances were chosen according to estimated K_ocrange of the test substance and generalized calibration graph was prepared. The reference substances were4-chloroaniline, 4-methylaniline, N methylaniline, 2-Nitrophenol, Nitrobenzene, 4-Nitrobenzamide, N,N-dimethylbenzamide, N-methylbenzamide, Benzamide, phenanthrene having K_ocvalue ranging from 1.239 to 4.09.The Log K_ocvalue was determined tobe 3.323± 0.0005at 25°C. By considering this log Koc value it is concluded that test chemical has moderate sorption to soil and sediments and slow migration potential to ground water.

Additional information

Stability:

Hydrolysis:

According to annex VIII column 2 of REACH regulation the study does not need to be conducted because the substance is readily biodegradable.

Biodegradation:

Biodegradation in water:

Two different experimental studies from differnt sources have been reviewed to determine biodegradaility of test chemical and their results are summarized below.

In first study the ready Biodegradability of test chemical was determined by the Manometric respirometry . The method used is basically the one described under No. 301 F in the  OECD Guidelines  forTesting of Chemicals.

A measured volume of inoculated   mineral   medium,  containing a known concentration of test substance 30 mg/L as the nominal  sole source of organic carbon, is stirred in a closed flask at a constant  temperature (± 1 °C) for up to 28 days.   Evolved   carbon  dioxide   is absorbed in sodium hydroxide pellets. The consumption  of oxygen  is determined  bymeasuring  the pressure drop in the respirometer  flask. The Biological Oxygen Demand (BOD), amount of oxygen taken up by the microbial population during  biodegradation of the test chemical (corrected for uptake by blank inoculum, run in parallel)  is expressed as a percentage of ThOD (Theoretical Oxygen Demand, calculated from the elemental composition, assuming that carbon is oxidized to carbon dioxide,  hydrogen to water and nitrogen to ammonium, nitrite or nitrate).

Test chemical undergoes 88% biodegradation after 28 days (87%after 62 days) in the test conditions. The10-day window criterionis also fulfilled (20% biodegradation on day 1 and 77% on day11). Thus, test chemical should be regarded as readily biodegradable according to this test.

Test chemical did not inhibit the intrinsic respiration of the inoculum at the test concentration and was therefore considered to be non-toxic to the inoculum at the test concentration.

In anothetr study the 28-days Manometric respirometry test following the OECD guideline 301F wasperformed to determine the ready biodegradability of the test chemical. % Degradation was calculated using the values of BOD and ThOD for test item and reference item.The BOD₂₈value of test chemicalwas observed to be 1.967 mgO₂/mg. ThOD was calculated as 2.424 mgO₂/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to manometric respirometry test was found to be 81.15%.Based on the results, the test item, under the test conditions, was determined to be readily-Biodegradable at 20 ± 1°C over a period of 28 days.

By considering results of both the studies mentioned above it can be concluded that test chemical is readily biodegradable in nature.

Biodegradation in water and sediments:

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test chemical. If released in to the environment, 24.8  % 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 chemical is not persistent in water and the exposure risk to aquatic animals is low whereas the half-life period of test chemical in sediment is estimated to be 135 days (3240  hrs). However, as the percentage release of test chemical into the sediment is less than 1% (i.e, reported as  0.406 %), indicates that test chemical is 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, 2018). If released into the environment, 72.6 % 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 chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is low.

Bioaccumulation:

Bioaccumulation: aquatic/sediments:

The estimated bio concentration factor (BCF) for tset chemical is 48.76 L/kg whole body w.w which does not exceed the bio concentration threshold of 2000. Thus it is concluded that test chemical is not expected to bioaccumulate in the food chain.

Transport and distribution:

Adsorption / desorption:

The adsorption coefficient Koc in soil and in sewage sludge of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals. The reference substances were chosen according to estimated K_ocrange of the test substance and generalized calibration graph was prepared. The reference substances were4-chloroaniline, 4-methylaniline, N methylaniline, 2-Nitrophenol, Nitrobenzene, 4-Nitrobenzamide, N,N-dimethylbenzamide, N-methylbenzamide, Benzamide, phenanthrene having K_ocvalue ranging from 1.239 to 4.09.The Log K_ocvalue was determined tobe 3.323± 0.0005at 25°C. By considering this log Koc value it is concluded that test chemical has moderate sorption to soil and sediments and slow migration potential to ground water.