Octyl acetate

Endpoint summary

Additional 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 Octyl acetate (CAS No. 112 -14 -1). The estimated half-life of Octyl acetate was estimated to be 4.808 yrs and 175.623 days at pH 7 and 8 (at 25ᵒC) respectively, indicating that it is rapidly hydrolysable.

Biodegradation in water

Predicted data for the test compoundOctyl acetate(CAS No. 112-14-1) and the study for its read across substance were reviewed for the biodegradation end point which are summarized as below:

 

Biodegradability of Geranyl butyrate (CAS no. 112-14-1) is predicted using QSAR toolbox version 3.4 (SSS QSAR Prediction Model, 2017). Test substance undergoes 84.90% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical Octyl acetate was estimated to be readily biodegradable in water.

 

Estimation Programs Interface Suite (EPI suite, 2017) was run to predict the biodegradation potential of the test compound Octyl acetate (CAS no. 112 -14 -1) 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 Octyl acetate is expected to be readily biodegradable.

 

Biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of read across substance Butyl carbitol acetate (CAS no. 124-17-4) (J-CHECK, 2016). Concentration of inoculum i.e, sludge used was 30 mg/l and initial substance conc. used in the study was 100 mg/l. The percentage degradation of read across substance was determined to be101, 100 and 98% degradation by BOD, GC and TOC removal in 28 days. Thus, based on percentage degradation, Butyl carbitol acetate was considered to be readily biodegradable in nature.

 

Biodegradation study was conducted for 14 days for evaluating the percentage biodegradability of read across substance Ethyl acetate (CAS no. 141-78-6) (J-CHECK, 2016). Concentration of inoculum i.e, sludge used was 30 mg/l and initial substance conc. used in the study was 100 mg/l. The percentage degradation of read across substance was determined to be 94, 95 and 100% degradation by BOD, TOC removal and GC in 14 days. Thus, based on percentage degradation, Ethyl acetate was considered to be readily biodegradable in nature.

 

Biodegradation study was conducted for 14 days for evaluating the percentage biodegradability of read across substance Methyl cellosolve acetate (CAS no. 110-49-6) (J-CHECK, 2016). Concentration of inoculum i.e, sludge used was 30 mg/l and initial substance conc. used in the study was 100 mg/l. The percentage degradation of read across substance was determined to be 95, 97 and 100% degradation by BOD, TOC removal and HPLC in 14 days. Thus, based on percentage degradation, Methyl cellosolve acetate was considered to be readily biodegradable in nature.

 

Biodegradation study was conducted employing dispersed seed aeration treatment for 10 days for evaluating the percentage biodegradability of read across substance Methyl cellosolve acetate (CAS no. 110-49-6) (HSDB, U. S. National Library of Medicine, 2016).The percentage degradation of read across substance was determined to be 69% by BOD in 10 days. Thus, based on percentage degradation, Methyl cellosolve acetate was considered to be readily biodegradable in water.

 

Biodegradation study was conducted for 5 days for evaluating the percentage biodegradability of read across substance Methyl cellosolve acetate (CAS no. 110-49-6) (A. L. BRIDIE, C. J. M. WOLFF and M. WINTER, 1979). The study was performed according to Standard dilution method (APHA "Standard Methods" No. 219 (1971)), but only deviation is that 0.5 mg/l allythiourea in each test was added to preventnitrification. Seed effluent was obtained from biological sanitary waste treatment plant. Test was carried out at a temperature of 20 ± 1°C. The 500-ml read across solutions were seeded with a filtered 10-ml volume of the effluent from a biological sanitary waste treatment plant. In each series of determinations, duplicate tests were also run on a mixture of glucose and glutamic acid. This is recommended in the APHA method as a means of checking the activity of the inoculum. The percentage degradation of read across substance was determined to be 30% degradation by ThOD in 5 days. Thus, based on percentage degradation, Methyl cellosolve acetate was considered to be readily biodegradable in nature.

On the basis of above results for target and read across substance, it can be concluded that the test substanceOctyl acetatecan be expected to be readily biodegradable in nature.

Biodegradation in water and sediment

Estimation Programs Interface (EPI) Suite (2017) prediction model was run to predict the half-life in water and sediment for the test compound Octyl acetate (CAS No. 112 -14 -1). If released in to the environment, 27.6% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of Octyl acetate in water is estimated to be 8.666 days (208 hrs). The half-life (8.666 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 Octyl acetate in sediment is estimated to be 77.916 days (1870 hrs). Based on this half-life value (77.916 days), it indicates that the chemical Octyl acetate is not persistent in sediment.

 

Biodegradation in soil

The half-life period of Octyl acetate (CAS No. 112 -14 -1) 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, 64.4% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of Octyl acetate in soil is estimated to be 17.333 days (416 hrs). Based on this half-life value of Octyl acetate, 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.

On the basis of available information, the test substanceOctyl acetatecan be considered to be readilybiodegradable in nature.

Adsorption / desorption:

Experimental and Predicted data of adsorption endpoint for the target chemical Octyl acetate (Cas no. 112-14-1) and its read across chemical were reviewed to summarize as follows:  

 

From predicted model EPI suite 2016 indicate that the soil adsorption coefficient (Koc) value of chemical Octyl acetate is estimated to be 204.5 L/kg (log KOC = 2.310) by means of MCI method at 25 deg.C, indicating that it is has a Moderate sorption to soil and sediment and therefore have slow migration potential to groundwater. 

 

Whereas from chemspider predicted database the soil adsorption coefficient i.e Koc value of test substance Octyl acetate was estimated to be 2921.84 L/Kg i.e Log Koc= 3.465 at pH 5.5 and 7.4. This Koc value indicates that the substance Octyl acetate has a Moderate sorption to soil and sediment and therefore have slow migration potential to groundwater.   

 

From HSDB database; 2016 the read across chemical Cyclohexyl acetate (Cas no. 622-45-7) indicate the adsorption coefficient (Koc) of substance Cyclohexyl acetate was found to be 650 using an estimated log Kow of 2.64 and a regression-derived equation.This Koc value suggests that cyclohexyl acetate is expected to have low mobility in soil.

Thus based on the above all studies it is concluded that the test substance Octyl acetate (Cas no. 112-14-1) has low mobility in soil/sediment.