Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Hydrolysis

The study does not need to be conducted because substance is readily biodegradable.

Biodegradation:

Biodegradation in water

Biodegradation study was conducted for 14 days for evaluating the percentage biodegradability of test chemical. Natural seawater obtained from Incheon Harbor, Korea was used as a test inoculum for the study. Seawater was filtered through Whatman GF/F glass fiber membrane firstly in order to remove the suspended particulate matter and the zooplankton that might prey upon the marine bacteria, and thus affect the biodegradation process of the test chemical.500 ml flask was used as a test vessel for the study.Initial test substance concentration used for the study was 100 mg/l.Two hundred milliliters filtered seawater was transferred to sterile 500 mL flasks and the surfactants were added, respectively, to give a final concentration of 100 mg/L. Triplicate flasks were set for each group. The flasks were shaken twice every day.The percentage degradation of test chemical was determined to be 50 and >90% after 1 and 5 days, respectively. Thus, based on percentage degradation, test chemical is considered to be readily biodegradable in nature.

Biodegradation in water and sediment

Estimation Programs Interface (2018) prediction model was run to predict the half-life in water and sediment for the test chemical. If released in to the environment, 16.5% 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 moderate to 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 0.403%), 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 (2018). If released into the environment, 83.1% 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 moderate to low.

he exposure risk to soil dwelling animals is moderate to low.

Bioaccumulation:

Bioaccumulation: aquatic / sediment

BCFBAF model of Estimation Programs Interface was used to predict the bioconcentration factor (BCF) of test chemical. The bioconcentration factor (BCF) of test chemical was estimated to be 70.79 L/kg whole body w.w at 25 °C which does not exceed the bio concentration threshold of 2000, indicating that the test chemical is non bioaccumulative in nature.

Transport and distribution:

Adsorption / desorption

KOCWIN model of Estimation Programs Interface was used to predict the soil adsorption coefficient i.e Koc value of test chemical .The soil adsorption coefficient i.e Koc value of test chemical was estimated to be 648 L/kg (log Koc= 2.81) by means of MCI method at 25 °C. This Koc value indicates that the test chemical has a moderate sorption to soil and sediment and therefore have slow migration potential to ground water.

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Additional information

Stability:

Hydrolysis

The study does not need to be conducted because substance is readily biodegradable.

Biodegradation:

Biodegradation in water:

Various experimental key and supporting studies for the test chemical were reviewed for the biodegradation end points which are summarized as below:

 

In an experimental key study from peer reviewed journal (Xiao-Xia Sun et. al., 2004), biodegradation experiment was conducted for 14 days for evaluating the percentage biodegradability of test chemical . Natural seawater obtained fromIncheon Harbor, Korea was used as a test inoculum for the study. Seawater was filtered through Whatman GF/F glass fiber membrane firstly in order to remove the suspended particulate matter and the zooplankton that might prey upon the marine bacteria, and thus affect the biodegradation process of the surfactants.500 ml flask was used as a test vessel for the study. Initial test substance concentration used for the study was 100 mg/l.Two hundred milliliters filtered seawater was transferred to sterile 500 mL flasks and the surfactants were added, respectively, to give a final concentration of 100 mg/L. Triplicate flasks were set for each group. The flasks were shaken twice every day. The percentage degradation of test chemical was determined to be 50 and >90% after 1 and 5 days, respectively. Thus, based on percentage degradation, test chemical is considered to be readily biodegradable in nature.

 

Another biodegradation study was conducted for 30 days for evaluating the percentage biodegradability of test chemical (handbook and secondary source, 2008). The study was performed according to OECD Guideline 301 D "Ready Biodegradability: Closed Bottle Test" under aerobic conditions. Activated sludge obtained from municipal sewage treatment plant effluent was used as a test inoculum for the study. Initial test substance concentration used for the study was 5 mg/l. The percentage degradation of test chemical was determined to be 84% by COD parameter in 30 days. Thus, based on percentage degradation, test chemical lis considered to be readily biodegradable in nature.

 

In a supporting study, biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of test chemical (handbook and secondary source IUCLID dataset, 2008). The study was performed according to OECD Guideline 301 E "Ready biodegradability: Modified OECD Screening Test"under aerobic conditions. Activated sludge obtained from municipal sewage treatment plant effluent was used as a test inoculum for the study. Initial test substance concentration used for the study was 10 mg/l based on DOC (dissolved organic carbon).The percentage degradation of test chemical was determined to be 90 and 100% by DOC removal parameter in 14 and 28 days. Thus, based on percentage degradation, test chemical is considered to be readily biodegradable in nature.

 

Additional biodegradation study (from secondary source (2000) and handbook) was conducted for 28 days for evaluating the percentage biodegradability test chemical. The study was performed according to OECD Guideline 302 B "Inherent biodegradability: Modified Zahn–Wellens Test "under aerobic conditions. Activated sludge was used as a test inoculum for the study. Initial test substance concentration used for the study was 250 mg/l. The percentage degradation of test chemical test chemical was determined to be 84 and 99% by COD parameter in 7 and 28 days. Thus, based on percentage degradation, test chemical is considered to be readily biodegradable in nature.

 

In an another supporting study from handbook (2008) and secondary source (IUCLID dataset, 2000), biodegradation experiment was conducted for 42 days for evaluating the percentage biodegradability of test chemical. The study was performed according to other guideline Anaerobic test with digester sludge: "Guidelines for Screening of Chemicals for Anaerobic Biodegradability "under anaerobic conditions. Other bacteria (digester sludge) obtained from municipal sewage treatment plant was used as a test inoculum for the study. Initial test substance concentration used for the study was 50 mg/l.The percentage degradation of test chemical test chemical was determined to be ranges from 25.1 to 60.9% by using evolution of CO2, CH4 and dissolved inorganic carbon % of organic carbon of test substance as a parameter after 42 days. Thus, based on percentage degradation, test chemical is considered to be inherently biodegradable in nature.

 

Biodegradation study from secondary source (2017) was conducted for 28 days for evaluating the percentage biodegradability of test chemical .The study was performed according to OECD Guide-line 301 D "Ready Biodegradability: Closed Bottle Test" under aerobic conditions at a temperature of 20°C. Effluent of stp Hochdahl treating predominantly domestic sewage was used as a test inoculum for the study. Initial test substance concentration used for the study was 2 and 5 mg/l, respectively. The test substance was measured for ready biodegradability in a closed bottle system. Aliquots of stock solution at concentrations of 2 and 5 mg/l were transferred to a mineral nutrient solution, inoculated with purification plant effluent and poured, without air bubbles, into bottles of known volume. The closed bottles were incubated at a constant 20 ± 1 °C in the dark or in diffused light and the biochemical oxygen demand of the test substance was measured using the Winkler Titration Method. Biodegradability was calculated as %BOD/ThOD or %BOD/COD. As a reference substance, an inoculated nutrient solution containing inoculant consumption control (IZK) and sodium benzoate was tested as well. Reference substance Benzoic acid, sodium salt undergoes 75 and 93% degradation after 7 and 21 days, respectively. The percentage degradation of test chemical was determined to be 44, 82 and 93% by BOD parameter in 5, 15 and 28 days, respectively. 14 day window criterion was fulfilled. Thus, based on percentage degradation, test chemical is considered to be readily biodegradable in nature.

 

Additional biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of test chemical (secondary source, 2017). The study was performed according to OECD Guide-line 301 D "Ready Biodegradability: Closed Bottle Test" under aerobic conditions at a temperature of 21°C. Activated sludge, domestic of 2 mg/l obtained from aeration stage of the Severn Trent Plc sewage treatment plant at Belper, Derbyshire, treating predominantly domestic sewage was used as a test inoculum for the study. Test inoculum was homogenised for 10 minutes, allowed to settle and the supernatant filtered through Whatman GFA filter paper (first 200 ml discarded). BOD bottles (darkened glass) with ground glass stoppers of 250-300 ml was used as a test vessel for the study. Standard culture medium was used as a test medium for the study. Experiment was performed in duplicates. COD was determined using a semi-microsample digestion (Hach) technique, Dissolved oxygen was determined using a Yellow Springs BOD Probe (Model 54). Closed vessels used: 250-300 ml BOD bottles (darkened glass) with ground glass stoppers. Measurement of dissolved oxygen at 0, 5, 15 and 28 days was carried outby means of a Yellow Springs BOD Probe (Model 54). Chemical Oxygen Demand was determined using a semi-micro sample digestion (Hach) technique. Reaction vials containing premeasured amounts of sulphuric acid, potassium dichromate, silver catalyst plus 2 ml water sample were heated at 150 °C for 2 hours and the COD values read from a Hach DR/2000 Direct Reading Spectrophotometer. Benzoic acid, sodium salt (3 mg/l) was used as a reference substance for the study. Control system includes both non-inoculated and inoculated culture medium. Reference substance Benzoic acid, sodium salt undergoes 73 and 93% degradation after 5 and 15 days, respectively. The percentage degradation of test chemical was determined to be 44, 82 and 93% by BOD parameter in 5, 15 and 28 days, respectively. Thus, based on percentage degradation, test chemical is considered to be readily biodegradable in nature.

 

For the test chemical, biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of test chemical .The study was performed according to OECD Guideline 301 D "Ready Biodegradability: Closed Bottle Test" under aerobic conditions at a temperature of 20°C. Effluent of stp Hochdahl treating predominantly domestic sewage was used as a test inoculum for the study. Initial test substance concentration used for the study was 2 and 5 mg/l, respectively. The test substance was measured for ready biodegradability in a closed bottle system. Aliquots of stock solution at concentrations of 2 and 5 mg/l were transferred to a mineral nutrient solution, inoculated with purification plant effluent and poured, without air bubbles, into bottles of known volume. The closed bottles were incubated at a constant 20 ± 1 °C in the dark or in diffused light and the biochemical oxygen demand of the test substance was measured using the Winkler Titration Method. Biodegradability was calculated as %BOD/ThOD or %BOD/COD. As a reference substance, an inoculated nutrient solution containing inoculant consumption control (IZK) and sodium benzoate was tested as well. Reference substance Benzoic acid, sodium salt undergoes 75 and 93% degradation after 7 and 21 days, respectively. The percentage degradation of test chemical was determined to be 44, 82 and 93% by BOD parameter in 5, 15 and 28 days, respectively. 14 day window criterion was fulfilled. Thus, based on percentage degradation, test chemical is considered to be readily biodegradable in nature.

 

In a supporting study from secondary source (2017), biodegradation experiment was conducted for 35 days for evaluating the percentage biodegradability of test chemical. The study was performed according to OECD Guideline 301 B "Ready Biodegradability: Modified Sturm Test (CO2 evolution)" under aerobic conditions at a temperature of 21±1°C. Activated sludge was used as a test inoculum for the study. 5L-carboys was used as a test vessel for the study. Aniline (20 mg DOC/l) was used as a reference substance for the study. Three liters of mineral nutrient solution were added to each of five, 5-l carboys. To two carboys were added test substance (equivalent concentrations to achieve 10 and 20 mg organic carbon/l), two carboys were maintained as blank test flasks, and one carboy was added reference substance (aniline) at 20 mg organic carbon/l. Inoculum was added to all carboys (30 ml containing 10(8) cells/ml), and the carboys were aerated with CO2-free air (30 - 50 ml/minute) with the effluent air passing through a series of CO2 traps containing Ba(OH)2. The CO2 produced by the degradation of the test substance by the inoculum was subsequently trapped in the Ba(OH)2 solution. The amount of CO2 produced was determined by titrating the Ba(OH)2 with HCl. Biodegradation was determined in two manners. First, biodegradation was calculated as the amount of CO2 collected in the trapping solution divided by the amount of CO2 that could theoretically have been produced based on the amount of carbon (as test substance) added to the test vessels. Second, biodegradation was measured as the amount of dissolved organic carbon removed from the test vessels. Reference substance Aniline undergoes 82% degradation after 35 days, respectively. Evolution of CO2 in the 10 mg organic carbon/l treatment was 71 and 71% at days 29 and 35, respectively. Evolution of CO2 in the 20 mg organic carbon/l treatment was 57 and 58% at days 29 and 35, respectively. Percent removal of dissolved organic carbon in the 10 mg organic carbon/l treatment was 88.5 and 93% at 29 days and 35 days, respectively. Percent removal of dissolved organic carbon in the 20 mg organic carbon/l treatment was 81 and 90%, respectively. Thus, based on percentage degradation, test chemical is considered to be readily biodegradable in nature.

 

Another supporting biodegradation study from secondary source (IUCLID dataset, 2000) was conducted for 20 days for evaluating the percentage biodegradability of test chemical. The study was performed according to Directive 84/449/EEC, C.5 "Biotic degradation – modified Sturm test "under aerobic conditions. Initial test substance concentration used for the study was 20 mg/l. The percentage degradation of test chemical test chemical was determined to be 100% after 20 days. Thus, based on percentage degradation, test chemical is considered to be readily biodegradable in nature.

 

Additional biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of test chemical (secondary source, 2000). The study was performed according to OECD Guideline 302 B "Inherent biodegradability: Modified Zahn–Wellens Test" under aerobic conditions. Activated sludge (domestic) was used as a test inoculum for the study. Initial test substance concentration used for the study was 500 mg/l. The percentage degradation of test chemical test chemical was determined to be 97% by DOC removal or COD parameter in 28 days. Thus, based on percentage degradation, test chemical is considered to be readily biodegradable in nature.

 

On the basis of above overall results for target chemical test chemical (from peer reviewed journal, handbook and secondary source), it can be concluded that the test substance test chemical is considered to be readily biodegradable in nature.

Biodegradation in water and sediment

Estimation Programs Interface (2018) prediction model was run to predict the half-life in water and sediment for the test chemical. If released in to the environment, 16.5% 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 moderate to 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 0.403%), indicates that test chemical is not persistent in sediment.

In addition to this, biodegradation endpoint can also be considered for waiver as per in accordance with column 2 of Annex IX of the REACH regulation, testing for this end point is scientifically not necessary and does not need to be conducted since the test chemical is readily biodegradable in water.

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 (2018). If released into the environment, 83.1% 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 moderate to low.

Bioaccumulation:

Bioaccumulation: aquatic / sediment

Various studies predicted have been conducted for test chemical and experimental study was reviewed for its structurally similar read across chemical to determine the bioaccumulation factor of test chemical and their results are summarized below. 

 

In first study the BCFBAF model of Estimation Programs Interface was used to predict the bioconcentration factor (BCF) of test chemical. The bioconcentration factor (BCF) of test chemical was estimated to be 70.79 L/kg whole body w.w at 25 °C .

 

In another study the Bioconcentration Factor (BCF) of test chemical was estimated using Chemspider database. The bioconcentration factor of test chemical was estimated to be 4.18 at both pH 5.5 and 7.4.

 

Next study was conducted for estimating the BCF (bioaccumulation factor) value of test chemical. The bioaccumulation factor (BCF) value was calculated using a log Kow of 5.82 and a regression-derived equation. The estimated BCF (bioaccumulation factor) value of test chemical was determined to be 600 dimensionless.

 

Last bioaccumulation study in fish was conducted for estimating the BCF (bioaccumulation factor) value of test chemical. The bioaccumulation factor (BCF) value was calculated using a log Kow of 5.13 and a regression-derived equation. The estimated BCF (bioaccumulation factor) value of test chemical was determined to be 48 dimensionless.

 

By considering results of all the studies mentioned above the BCF value of test chemical was determined to be in range of 4.18 to 600 dimensionless which does not exceed the bioconcentration threshold of 2000, indicating that the test chemical is non bioaccumulative in nature.

Transport and distribution:

Adsorption / desorption

Various studies predicted have been conducted for test chemical and experimental study was reviewed for its structurally similar read across chemical and their results are summarized below. 

 

In first study the KOCWIN model of Estimation Programs Interface was used to predict the soil adsorption coefficient i.e Koc value of test chemical. The soil adsorption coefficient i.e Koc value of test chemical was estimated to be 648 L/kg (log Koc= 2.81) by means of MCI method at 25 °C.

 

In another study the Soil Adsorption Coefficient i.e Koc value of test chemical was estimated using ChemSpider Database. The adsorption coefficient (Koc) value of test chemical was estimated to be 143.46 (Log Koc = 2.156) at pH 5.5 and 143.48 (Log Koc = 2.156) at pH 7.4.

 

In last experimental 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. A test chemical solution was prepared by accurately weighing 4 mg of test chemical and diluted with Methanol up to 10 ml. Thus, the test solution concentration was 400 mg/l. The pH of test substance was 7.15. 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. 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 were chosen according to functional similarity with the test substance and calibration graph prepared. The reference substances were 2 - nitrophenol, Nitrobenzene, 4-Nitrobenzamide, N,N-dimethylbenzamide, N-methylbenzamide, Benzamide having Koc value ranging from 1.239 to 2.47. The Log Koc value of test chemical was determined to be 1.8124 ± 0.002 dimensionless at 25°C.

 

By considering results of all the studies mentioned above the Log koc value of test chemical was determined to be in range of 1.8 to 2.81 dimensionless. This range log Koc value indicates that test substance has a low sorption to soil and sediment and therefore has moderate migration potential to ground water.