Diisopropyl adipate

Endpoint summary

Description of key information

Stability:

Hydrolysis:

According to annex VIII column 2 the study does not need to be conduced because the substance is readily biodegradable.

Biodegradation:

Biodegradation in water:

Estimation Programs Interface Suite (EPI suite, 2018) was run to predict the biodegradation potential of the test chemical in the presence of mixed populations of environmental microorganisms. The biodegradability of the substance was calculated using seven different models such as Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI Linear Model, MITI Non-Linear Model and Anaerobic Model (called as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical is expected to be readily biodegradable.

Biodegradation in water and sediments:

Estimation Programs Interface (EPI Suite, 2018) prediction model was run to predict the half-life in water and sediment for the test chemical. If released in to the environment, 28.3 % 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 0.137 %), 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, 69.7 % 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:
Using BCFBAF Program (v3.00) model of EPI suite (2018) the estimated bio concentration factor (BCF) for test chemical is 60.43 L/kg wet-wt at 25 deg. c which does not exceed the bioconcentration threshold of 2000. Therefore it is concluded that test chemical is nonbioaccumulative in food chain.

Transport and distribution:

Adsorption/desorption :

The Adsorption Coefficient of test substance was determined as per the HPLC method (OECD Guideline-121). The Log Koc value was determined to be 3.542 ± 0.008 at 25°C. Thus based on the result it is concluded that the test substance has a strong sorption to soil and sediment and therefore has negligible to slow migration potential to ground water.

Additional information

Stability:

Hydrolysis:

According to annex VIII column 2 the study does not need to be conduced because the substance is readily biodegradable.

Biodegradation:

Biodegradation in water:

Various studies have been reviewed for test chemical and its read across chemical for biodegradation endpoint and their results are summarized below.

The objective of the study was to measure Biochemical Oxygen Demand of test chemical over a 5-day period by closed bottle test and thereby calculating percentage degradation on the basis of its theoretical oxygen demand (ThOD). The test contained a control group, a reference group, and a test substance group. The solution of the test substance having a concentration of 2 mg/L in mineral medium, was inoculated with a 0.5 ml/L of surface water (used as inoculum) and kept in completely full closed bottles in BOD incubator at constant temperature of 20 ± 2°C. DO determination on the 0thand 5thday of the experiment was done using Winkler Azide Titration method. The amount of oxygen taken up by the microbial population during biodegradation of the test substance was corrected for uptake by the blank inoculum and BOD5was calculated accordingly. The biochemical degradation of the test substance is expressed as a percentage of ThOD. ThOD, BOD5and % Degradation of the test substance was determined to be 41.27% in 5 days. Thus based on these results it can be concluded that test chemical is readily biodegradable.

In next study the Estimation Programs Interface Suite (EPI suite, 2018) was run to predict the biodegradation potential of the test chemical in the presence of mixed populations of environmental microorganisms. The biodegradability of the substance was calculated using seven different models such as Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI Linear Model, MITI Non-Linear Model and Anaerobic Model (called as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical is expected to be readily biodegradable.

Another study was reviewed from authoritative database ( J check) in this study the Biodegradation experiment was carried out of test chemical by taking activated sludge as inoculums at 30 mg/L concentration for 14 days. Biodegradation was analyzed by using three parameters that are BOD and test material analysis by GC .The initial concentration of test chemical was 100 mg/L. After 2 weeks of incubation percent biodegradation of test chemical was observed to be 83 % by BOD (O2 consumption) parameter, 92 % by TOC removal parameters and 100 % by test material analysis by GC parameter in 14 days. By considering % degradation values it is concluded that test chemical is readily biodegradable.

 

Last study was also reviewed from J check in this the Biodegradation experiment was performed for test chemical by taking activated sludge as inoculums at 30 mg/L concentration for 14 days. Biodegradation was analyzed by using two parameters that are BOD and test material analysis by GC. The initial concentration of test chemical was 100 mg/L. After 2 weeks of incubation Percent biodegradation of test chemical was observed to be 90% by BOD (O2 consumption) parameter and 100 % by test material analysis by GC parameter in 14 days. On the basis of percent degradation values it is concluded that test chemical is readily biodegradable. 

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

Biodegradation in water and sediments:

Estimation Programs Interface (EPI Suite, 2018) prediction model was run to predict the half-life in water and sediment for the test chemical. If released in to the environment, 28.3 % 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 0.137 %), 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, 69.7 % 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:

Various studies have been reviewed for test chemical for Bioaccumulation in aquatic organisms endpoint and their results are summarized below.

The first study was done by using BCFBAF Program (v3.00) model of EPI suite (2018) in this study the bio concentration factor (BCF) for test chemical was estimated to be 60.43 L/kg wet-wt at 25 deg. c.

Next study was done by using Bio-concentration Factor (v12.1.0.50374) module of ACD lab in this study the Bio-concentration Factor at range pH 1 -14 was estimated to be 77.4 dimensionless. This value indicates that the chemical is non-bioaccumulative in aquatic organisms.

Last study was reviewed fromsupporting documents of High Production Volume Chemicals in this studythe Bioaccumulation concentration Factor (BCF) of test chemical was estimated to be 59 dimensionless. BY considering this BCF value it is concluded that test chemical is non-bioaccumulative in nature.

By considering results of all the studies mentioned above it can be concluded that test chemical is non-bioaccumulative in nature.

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 solutions of the test substance and reference substances were prepared in appropriate solvents. A test item solution was prepared by accurately weighing 50mg of test item and diluted with mobile phase up to 100ml. Thus, the test solution concentration was 500mg/l. The pH of test substance was 6.30. Each of the reference substance and test substance were analysed by HPLC at 210 nm. After equilibration of the HPLC system, Urea was injected first, the reference substances were injected in duplicate, followed by the test chemical solution in duplicate. Reference substances were injected again after test sample, no change in retention time of reference substances was observed. Retention time tR were measured, averaged and the decimal logarithms of the capacity factors k were calculated. The graph was plotted between log Koc versus log k(Annex - 2).The linear regression parameter of the relationship log Koc vs log k were also calculated from the data obtained with calibration samples and therewith, log Koc of the test substance was determined from its measured capacity factor. The reference substances Phenol, aniline, nitrobenzene, 4- nitro phenol, 2-nitrophenol and DDT were chosen having Koc value range from 1.32 to 5.63.

The Log Koc value of test chemical was determined to be 3.542 ± 0.008 dimensionless at 25°C.This log Koc value indicates that the substance has a strong sorption to soil and sediment and therefore has negligible to slow migration potential to ground water.