Isononyl acetate

Endpoint summary

Description of key information

Hydrolysis:

HYDROWIN v2.00 program of Estimation Programs Interface (EPI Suite, 2017) prediction model was used to predict the hydrolysis half-life of test compound 7-methyloctyl acetate (CAS No. 40379 -24 -6). The estimated half-life of 7-methyloctyl acetate was estimated to be 2.142 years at pH 7.0 and 78.232 days at pH 8.0 (at 25 deg C), indicating that it is not hydrolysable.

Biodegradation in water:

Biodegradability of 7-methyloctyl acetate (CAS no. 40379 -24 -6) is predicted using OECD QSAR toolbox version 3.4 with logKow as the primary descriptor. Test substance undergoes 90.83 % degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical 7-methyloctyl acetate was estimated to be readily biodegradable in water.

Biodegradation in water and sediment: simulation tests:

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound 7 -methyloctyl acetate (CAS No. 40379 -24 -6). If released in to the environment, 27.3 % of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of 7-methyloctyl acetate 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 7-methyloctyl acetate 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 0.368%), indicates that 7-methyloctyl acetate is not persistent in sediment.

Biodegradation in soil:

The half-life period of 7-methyloctyl acetate (CAS No.40379 -24 -6) 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, 65.8 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of 7-methyloctyl acetate in soil is estimated to be 30 days (720 hrs). Based on this half-life value of 7-methyloctyl acetate, it is concluded that the chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is low.

Bioaccumulation: aquatic/sediment:

BCFBAF model (v3.01) of Estimation Programs Interface (EPI Suite, 2017) was used to predict the bioconcentration factor (BCF) of test chemical 7-methyloctyl acetate (CAS No. 40379 -24 -6). The bioconcentration factor (BCF) of 7-methyloctyl acetate was estimated to be 286.4 L/kg whole body w.w (at 25 deg C) which does not exceed the bio concentration threshold of 2000, indicating that the chemical 7-methyloctyl acetate is not expected to bioaccumulate in the food chain.

 

Adsorption / desorption:

The Soil Adsorption Coefficient i.e Koc value of test substance 7-methyloctyl acetate was estimated using Adsorption Coefficient module (v12.1.0.50374) program as Koc 4849 (log Koc= 3.7 ± 1.0). This Koc value indicates that the test substance 7-methyloctyl acetate has a strong sorption to soil and sediments and therefore has negligible to slow migration potential to groundwater.

Additional information

Hydrolysis:

Predicted data for the target chemical 7-methyloctyl acetate (CAS No. 40379 -24 -6) and various supporting weight of evidence studies from authoritative database for its read across substance were reviewed for the hydrolysis end point which are summarized as below: 

 

In a prediction using the HYDROWIN v2.00 program of Estimation Programs Interface (EPI Suite, 2017) prediction model was used to predict the hydrolysis half-life of test compound 7-methyloctyl acetate (CAS No. 40379 -24 -6). The estimated half-life of 7-methyloctyl acetate was estimated to be 2.142 years at pH 7.0 and 78.232 days at pH 8.0 (at 25 deg C), indicating that it is not hydrolysable.

In a supporting weight of evidence study from authoritative database (HSDB, 2017) for the read across chemical 3-methyl-1-butyl acetate (CAS no. 123-92-2), the half-life and base catalyzed second order hydrolysis rate constant was determined using a structure estimation method of the read across chemical 3-methyl-1-butyl acetate. The second order hydrolysis rate constant of 3-methyl-1-butyl acetate was determined to be 0.1L/mol-sec with a corresponding half-lives of 2 yrs and 78 days at pH 7 and 8, respectively.  

In a supporting weight of evidence study from authoritative database (HSDB, 2017) for the read across chemical 2-methylpropyl 2-methylprop-2-enoate (CAS no. 97-86-9), the half-life and base catalyzed second order hydrolysis rate constant was determined using a structure estimation method of the read across chemical 2-methylpropyl 2-methylprop-2-enoate. The second order hydrolysis rate constant of 2 -methylpropyl 2 -methylprop-2 -enoate was determined to be 0.018L/mol-sec with a corresponding half-lives of 130 and 13 yrs at pH 7 and 8, respectively.

 

On the basis of the above results for target chemical 7-methyloctyl acetate (CAS No. 40379 -24 -6) (from EPI Suite, 2017) and for its read across substance (from authoritative database HSDB, 2017), it can be concluded that the test chemical 7-methyloctyl acetate is not hydrolysable.

Biodegradation in water:

Experimental and predicted data for the target compound 7-methyloctyl acetate (CAS no. 40379 -24 -6) and various supporting weight of evidence studies for its read across substance were reviewed for the biodegradation end point which are summarized as below:

 

In a prediction done by SSS (2017) using OECD QSAR toolbox version 3.4 with logKow as the primary descriptor, percentage biodegradability of test chemical 7-methyloctyl acetate was estimated. Biodegradability of 7-methyloctyl acetate (CAS no. 40379 -24 -6) is predicted. Test substance undergoes 90.83 % degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical 7-methyloctyl acetate was estimated to be readily biodegradable in water.

 

In a prediction using the estimation Programs Interface Suite (EPI suite, 2017) was run to predict the biodegradation potential of the test compound 7-methyloctyl acetate (CAS no. 40379 -24 -6) 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 the test chemical 7-methyloctyl acetate is expected to be readily biodegradable.

 

In a supporting weight of evidence study from peer reviewed journal (Kenneth S. Price, et. al; 1974) and authoritative database (HSDB, 2017) for the read across chemical 2-methyl propyl acetate (CAS no. 110-19-0), biodegradation experiment was conducted for 20 days for evaluating the percentage biodegradability of read across substance 2-methyl propyl acetate (CAS no. 110-19-0). Initial test substance conc. used in the study was 3, 7 and 10 mg/l, respectively. Domestic wastewater was used as a test inoculum. The BOD bottles were half filled with aerated dilution water containing the specified minerals and buffer. Small aliquots of the test chemicals were added to these bottles from 0.1% stock solutions yielding conc. of 3, 7 and 10 mg/l. At least two of these concentrations were tested in duplicate. These concentrations gave a potential oxygen demand of 3 to 30 mg/l over the 20 days duration of test. Dissolved oxygen was monitored periodically in the individual bottles through the use of a commercial DO meter filled with an agitated probe. The bottles were opened for sampling and DO measurements about five times during the course of the 20 day test. The percentage degradation of substance 2-methyl propyl acetate was determined to be 60, 74, 79 and 81% in 5, 10, 15 and 20 days, respectively. Thus, based on percentage degradation, 2-methyl propyl acetate is considered to be readily biodegradable in nature.

 

Another biodegradation study was conducted for 14 days for evaluating the percentage biodegradability of read across substance 3-methylbutyl 2-hydroxybenzoate (CAS no. 87-20-7) (J-CHECK, 2017 and Envichem, 2014). The study was performed according to OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I)). Concentration of inoculum i.e, sludge used was 30 mg/l and initial test substance conc. used in the study was 100 mg/l, respectively. The percentage degradation of substance 3-methylbutyl 2-hydroxybenzoate was determined to be 83.4 and 100% by BOD and GC parameter in 14 days. Thus, based on percentage degradation, 3-methylbutyl 2-hydroxybenzoate is considered to be readily biodegradable in nature.

 

In a supporting weight of evidence study from peer reviewed journal (A.M. Api, et. al; 2017), biodegradation experiment was conducted for 28 days for evaluating the percentage biodegradability of test substance 3-Methylbutyl propanoate (CAS no. 105-68-0). The study was performed according to OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test).The percentage degradation of test substance 3-Methylbutyl propanoate was determined to be 74% by O2 consumption parameter in 28 days. Thus, based on percentage degradation, 3-Methylbutyl propanoate is considered to be readily biodegradable in nature.

 

 On the basis of above results for target chemical 7-methyloctyl acetate (CAS no. 40379 -24 -6) (from QSAR toolbox and EPI suite, 2017) and for its read across substance (from peer reviewed journal, authoritative database J-CHECK, HSDB and Envichem, 2014), it can be concluded that the test substance 7-methyloctyl acetate can be expected to be readily biodegradable in nature.

Biodegradation in water and sediment: simulation tests:

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound 7 -methyloctyl acetate (CAS No. 40379 -24 -6). If released in to the environment, 27.3 % of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of 7-methyloctyl acetate 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 7-methyloctyl acetate 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 0.368%), indicates that 7-methyloctyl acetate is not persistent in sediment.

Biodegradation in soil:

The half-life period of 7-methyloctyl acetate (CAS No.40379 -24 -6) 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, 65.8 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of 7-methyloctyl acetate in soil is estimated to be 30 days (720 hrs). Based on this half-life value of 7-methyloctyl acetate, it is concluded that the chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is low.

Bioaccumulation: aquatic/sediment:

Various predicted data for the target compound 7-methyloctyl acetate (CAS no. 40379 -24 -6) and supporting weight of evidence study for its read across substance were reviewed for the bioaccumulation end point which are summarized as below:

 

In a prediction done using BCFBAF model (v3.01) of Estimation Programs Interface (EPI Suite, 2017) was used to predict the bioconcentration factor (BCF) of test chemical 7-methyloctyl acetate (CAS No. 40379 -24 -6). The bioconcentration factor (BCF) of 7-methyloctyl acetate was estimated to be 286.4 L/kg whole body w.w (at 25 deg C) which does not exceed the bio concentration threshold of 2000, indicating that the chemical 7-methyloctyl acetate is not expected to bioaccumulate in the food chain.

 

In a second predicted report Using Bio-concentration Factor (v12.1.0.50374) module Bio-concentration Factor over the entire pH scale of the test substance 7-methyloctyl acetate estimated to be 989. This value indicates that the test substance 7-methyloctyl acetate was considered to be non-accumulative in aquatic organisms.

 

Similarly Bioconcentration Factor (BCF) of test chemical 7-methyloctyl acetate (CAS no. 40379 -24 -6) was estimated using Chemspider database. The bioconcentration factor of test substance 7-methyloctyl acetate was estimated to be 1007.03 at both pH 5.5 and 7.4, respectively, which does not exceed the bioconcentration threshold of 2000, indicating that the chemical 7-methyloctyl acetate is not expected to bioaccumulate in the food chain.

 

From CompTox Chemistry Dashboard using OPERA (OPEn (quantitative) structure-activity Relationship Application)  V1.02 model in which calculation based on PaDEL descriptors (calculate molecular descriptors and fingerprints of chemical)  the bioaccumulation i.e BCF for test substance 7-methyloctyl acetate was estimated to be 96.6 dimensionless . The predicted BCF result based on the 5 OECD principles. Thus based on the result it is concluded that the test substance 7-methyloctyl acetate is non-bioaccumulative in nature.

 

Similarly in a supporting weight of evidence study from authoritative database HSDB, 2017 for the read across chemical 3 -methyl-1-butyl acetate, the bioaccumulation study in fish was conducted for estimating the BCF (bioaccumulation factor) value of test chemical 3 -methyl-1-butyl acetate (CAS no. 123-92-2). The bioaccumulation factor (BCF) value was calculated using a log Kow of 2.25 and a regression equation. The estimated BCF (bioaccumulation factor) value of 3-methyl-1-butyl acetate in fish was determined to be 14 dimensionless, which does not exceed the bioconcentration threshold of 2000, indicating that the chemical 3-methyl-1-butyl acetate is considered to be non-accumulative in aquatic organisms.

 

On the basis of above results for target chemical (CAS no. 40379 -24 -6) (from EPI suite, ACD labs and CompTox Chemistry Dashboard and Chemspider 2017) and for its read across substance (from authoritative database HSDB, 2017), it can be concluded that the BCF value of test substance (CAS no. 40379 -24 -6) ranges from 96.6-1007.03 which does not exceed the bioconcentration threshold of 2000, indicating that the chemical is not expected to bioaccumulate in the food chain.   

Adsorption / desorption:

Various predicted data for the target compound 7-methyloctyl acetate (CAS no. 40379 -24 -6) and supporting weight of evidence study for its read across substance were reviewed for the adsorption end point which are summarized as below:

 

In a prediction the Soil Adsorption Coefficient i.e Koc value of test substance 7-methyloctyl acetate was estimated using Adsorption Coefficient module (v12.1.0.50374) program as Koc 4849 (log Koc= 3.7 ± 1.0). This Koc value indicates that the test substance 7-methyloctyl acetate has a strong sorption to soil and sediments and therefore has negligible to slow migration potential to groundwater.

 

In an another prediction done by using ChemSpider Database (2017), The Soil Adsorption Coefficient i.e Koc value of test substance 7-methyloctyl acetate (CAS no.40379 -24 -6) was estimated using ChemSpider Database. The adsorption coefficient (Koc) value of substance 7-methyloctyl acetate was estimated to be 4911.08 (Log Koc = 3.69) at pH 5.5 and 7.4, respectively. This Koc value indicates that the substance 7-methyloctyl acetate has a strong sorption to soil and sediment and therefore have negligible to slow migration potential to groundwater.

 

From CompTox Chemistry Dashboard using OPERA (OPEn (quantitative) structure-activity Relationship Application)  V1.02 model in which calculation based on PaDEL descriptors (calculate molecular descriptors and fingerprints of chemical)  the adsorption coefficient i.e KOC for test substance 7-methyloctyl acetate was estimated to be 658 L/kg. Thus based on the result it is concluded that the test substance 7-methyloctyl acetate have moderate sorption to soil and sediment, slow migration potential to groundwater.

 

 

Similarly in a supporting weight of evidence study from UERL report, 2017 for the read across chemical isopentyl salicylate (CAS No. 87-20-7) Koc determined. The adsorption coefficient Koc in soil and in sewage sludge isopentyl salicylate (CAS No. 87-20-7) 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 structural similarity of the test substance and calibration graph was prepared. The reference substances were Phenol, Toluene, Ethylbenzene, Naphthalene, Phenanthrene and DDT having Koc value ranging from 1.32 to 5.63. The Log Koc value was 4.202 ± 0.002 at 25°C.

 

 

On the basis of above overall results for target chemical 7-methyloctyl acetate (CAS no. 40379 -24 -6)  (from ACD labs, ChemSpider and CompTox Chemistry Dashboard, 2017), and for its read across substance (UERL report, 2016) it can be concluded that the Koc value of test substance 7-methyloctyl acetate ranges from 658 - 4911.08 indicating that the test chemical 7-methyloctyl acetate has a moderate to strong sorption to soil and sediment and therefore have negligible to slow migration potential to ground water.