Poly(oxy-1,2-ethanediyl),α-hydro-ω-hydroxy- Ethane-1,2-diol, ethoxylated

Endpoint summary

Description of key information

Stability:

Hydrolysis:

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

Biodegradation:

Biodegradation in water:

28-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 inoculum . The concentration of test and reference item (Sodium Benzoate) chosen for both the study was 4 mg/L, while that of inoculum was 32ml/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 78.31 %. 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 BOD28 value of test chemical was observed to be 1.25 mgO2/mg. ThOD was calculated as 1.67 mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 74.85 %. Based on the results, the test item, under the test conditions, was considered to be readily biodegradable in nature.

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, 30.6 % 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 0.0688 %), 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, 69.4 % 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 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 3.162 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 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. 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 substance 4-chloroaniline, 4-methylaniline(p-Tolouidine), N-methylaniline, p-toluamide, Aniline, 2,5-Dichloroaniline, 4-nitrophenol, 2 - nitrophenol, 2-nitrobenzamide, 3-nitrobenzamide, Nitrobenzene, 4- Nitrobenzamide, 1-naphthylamine, 1-naphtol, Direct Red 81, Benzoic acid methylester, Carbendazim, Benzoic acid phenylester, Xylene, Ethylbenzene, Toluene, Naphthalene, 1,2,3-trichlorobenzene, Pentachlorophenol, Phenol, N,N-dimethylbenzamide, 3,5-dinitrobenzamide, N-methylbenzamide, Benzamide, phenantrene;phenanthrene, DDT, Acetanilide were chosen having Koc value range from 1.239 to 4.09.

The Log Koc value of test chemical was determined to be 1.8568 dimensionless at 25°C.This log Koc value indicates that the substance has a low sorption to soil and sediment and therefore has moderate migration potential to ground water.

Additional information

Stability:

Hydrolysis:

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

Biodegradation:

Biodegradation in water:

Different experimental studies have been reviewed from study report and peer reviewed journal for Biodegradation in water endpoint and their results are summarized below.

 

In first study the 28-days Closed Bottle test following the OECD guideline 301 D was performed 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 inoculum . The concentration of test and reference item (Sodium Benzoate) chosen for both the study was 4 mg/L, while that of inoculum was 32ml/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 78.31 %. 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 BOD28 value of test chemical was observed to be 1.25 mgO2/mg. ThOD was calculated as 1.67 mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 74.85 %. Based on the results, the test item, under the test conditions, was considered to be readily biodegradable in nature.

 

 

Another study was reviewed from authoritative database ( J check) in this percent degradation of test chemical was determined by using various parameters and activated sludge at concentration 30 mg/L concentration as inoculum and initial test chemical concentration used was 100 mg/L for 28 days.

The percent degradation of test chemical in 28 days was observed to be 56.2% and 53 % by O2 consumption (BOD) parameter  in the case where TOD is calculated by assuming n = 4 and n=10 respectively, by using parameter TOC removal test chemical showed 52.2 % degradation and by using test material analysis parameter (UV-Vis) percent degradation observed was 43.1.

By considering all the percent degradation value by various parameters it is concluded that test chemical is Ultimate inherently biodegradable in water.

 

Next study was reviewed from chemosphere Journal (1989) in this study an experiment was performed to determine percent degradation of test chemical by using sludge from the anaerobic digester of a sewage treatment plant treating predominantly domestic sewage as inoculum , mineral salt was used as medium and Oxygen was removed by sparging with pure nitrogen before use. The initial test chemical concentration used was 60 mg/L. Percent degradation of test chemical was observed to be 86 and 82 % by Gas production (theoretical and observed carbon dioxide and methane gas production ratios) as parameter in anaerobic condition in 37 days. BY considering percent degradation value it is concluded that test chemical is readily biodegradable.

 

Last study was also reviewed from chemosphere journal (1996) in this publication an experiment was performed to determine biodegradation potential of test chemical by using CO2 evolution as parameter. In this fortified BOD medium was used and bottle was connected CO2-free air apparatus. The test bottles were placed on a rotary shaker at room temperature and aerated overnight with agitation to purge the system of background CO2. After overnight aeration, the Ba(OH)2 traps were connected to the test system. The appropriate amount of test substance (20-40 mg/L) was added to the test bottles a 1% v/v (10 ml/L) activated sludge inoculum. The percent degradation of test chemical was determined to be 80% in days by considering CO2 evolution as parameter and activated sludge was used as inoculums. By considering this percent degradation value it is concluded that test chemical is readily biodegradable in water.

 

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

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, 30.6 % 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 0.0688 %), 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, 69.4 % 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 chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is low .

Bioaccumulation:

Bioaccumulation: aquatic/sediments:

Different predicted studies have been reviewed for bioaccumulation endpoint and their results are summarized below.

 

The first study was done by using BCFBAF Program (v3.00) model of EPI suite (2018) the estimated bio concentration factor (BCF) for test chemical is 3.162 L/kg wet-wt at 25 deg. c

 

Another study was done by using Bio-concentration Factor (v12.1.0.50374) module Bio-concentration Factor over the entire pH scale of the test substance estimated to be 1.0 dimensionless

 

By considering results of all the studies mentioned above it is concluded that test chemical This value indicates that the test substance is non-bioaccumulative in aquatic organisms.

 

This endpoint can also be considered for waiver according to annex IX coumn 2 because the substance has low potential for bioaccumulation based on log Kow<= 3

 

Transport and distribution:

Adsorption/desorption:

Different experimental studies have been reviewed from study report and peer reviewed journal for adsorption endpoint and their results are summarized below.

 

In first study 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. 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 substance 4-chloroaniline, 4-methylaniline(p-Tolouidine), N-methylaniline, p-toluamide, Aniline, 2,5-Dichloroaniline, 4-nitrophenol, 2 - nitrophenol, 2-nitrobenzamide, 3-nitrobenzamide, Nitrobenzene, 4- Nitrobenzamide, 1-naphthylamine, 1-naphtol, Direct Red 81, Benzoic acid methylester, Carbendazim, Benzoic acid phenylester, Xylene, Ethylbenzene, Toluene, Naphthalene, 1,2,3-trichlorobenzene, Pentachlorophenol, Phenol, N,N-dimethylbenzamide, 3,5-dinitrobenzamide, N-methylbenzamide, Benzamide, phenantrene;phenanthrene, DDT, Acetanilide were chosen having Koc value range from 1.239 to 4.09.

The Log Koc value of test chemical was determined to be 1.8568 dimensionless at 25°C.This log Koc value indicates that the substance has a low sorption to soil and sediment and therefore has moderate migration potential to ground water.

 

Another study was reviewed from publication from Colloid & Polymer Science journal in this study the Adsorption experiment was performed in that the apparent adsorption rate was obtained by 200 ml of test chemical solution of 200 mg. dm -3 was stirred at a high rate of 500 rpm, and 0.20 g of the adsorbent was added. Samples were taken out and filtered using 0.45 Fan membrane-filters immediately. The residual concentration of the filtrate was determined by a total organic carbon analyzer. After analyzing The test chemical adsorbed only 5 % in 30 min on montmorillonite-Na clay. On the basis of this it is concluded that test chemical showed low sorption on montmorillonite-Na clay. The apparent adsorption rate was obtained by 200 ml of test chemical solution of 200 mg. dm -3 was stirred at a high rate of 500 rpm, and 0.20 g of the adsorbent was added. Samples were taken out and filtered using 0.45 Fan membrane-filters immediately. The residual concentration of the filtrate was determined by a total organic carbon analyzer. After analyzing The test chemical adsorbed only 5 % in 30 min on montmorillonite-Na clay. On the basis of this it is concluded that test chemical showed low sorption on montmorillonite-Na clay.

 

Last study was reviewed from environmental science technology journal (1987) in this study the adsorption desorption experiment was performed to determine adsorption capacity of test chemical on sediments EPA 5 and EPA 14 the sediments were obtained from the Environmental Research Laboratory, Athens, GA . Adsorption isotherms were determined by batch equilibration. The dry sediments were equilibrated with 0.01 M CaSO4, for 5 days at 4 oC before they were used in sorption experiments. The wet sediment was weighed into 25-mL glass centrifuge tubes and 25-mL aliquots of the sorbate solutions were pipetted into the centrifuge tubes containing the sediment.The sorption tubes were rotated end-over-end for approximately 16 h in a thermostated box at 25 oC,then samples were Centrifuged for 1 hour at 10000 rpm and 25 oC. After that Differential refractometry was used to analyze the supernatant solutions of the test chemical. Langmuir Parameters and percent desorption were calculated. Adsorption capacity of test chemical on sediment EPA 5 and EPA 14 was 11.1 mg/g and 5.9 mg/g respectively. On the basis of these values it is concluded that test chemical has low sorption to soil.

 

 By considering results of all the studies mentioned above it is concluded that test chemical has low sorption potential to soil and sediment therefore has moderate migration potential to ground water.