Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Stability:

Hydrolysis:

Half life of hydrolysis of test chemical 3-(bromomethyl)benzonitrile was estimated by using HYDROWIN Program (v2.00) of EPI suite. The half life of hydrolysis of test chemical 3-(bromomethyl)benzonitrile was estimated to be 1.32 hrs. Based on this half life value it is concluded that test chemical 3-(bromomethyl)benzonitrile is rapidly hydrolysable.

Biodegradation:

Biodegradation in water:

Biodegradability of test chemical 3-(bromomethyl)benzonitrile was estimated by using OECD QSAR tool box v3.3 and eight closest read across chemicals with log Kow as primary descriptor. Percent biodegrdation of test chemical 3-(bromomethyl)benzonitrile was estimated to be 9.1125 % by considering BOD as parameter and microorganisms as inoculum in 28 days. Based on the percent biodegradability it is concluded that this test chemical is not readily biodegradable.

Biodegradation in water and sediments:

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound 3-(bromomethyl)benzonitrile (CAS no.28188 -41 -2) . If released in to the environment, 19.7 % 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 37.5 days (360 hrs). The half-life (37.5days 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 3-(bromomethyl)benzonitrile in sediment is estimated to be 337.5 days (8100 hrs). However, as the percentage release of test chemical into the sediment is less than 1% (i.e, reported as 0.327 %), indicates that test chemical 3-(bromomethyl)benzonitrile is not persistent in sediment as well.

Biodegradation in Soil:

The half-life period of test chemical 3-(bromomethyl)benzonitrile (CAS no.28188-41-2) 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, 77.2 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical 3-(bromomethyl)benzonitrile in soil is estimated to be 75 days (1800 hrs). Based on this half-life value of test chemical 3-(bromomethyl)benzonitrile, 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 2017 the estimated bio concentration factor (BCF) for 3-(bromomethyl)benzonitrile (CAS No. 28188-41-2) is 18.66 L/kg wet-wt at 25 deg. c which does not exceed the bioconcentration threshold of 2000. Therefore it is concluded that test chemical 3-(bromomethyl)benzonitrile is non bioaccumulative in food chain.

Transport and Distribution:

Adsorption/desorption:

The Soil Adsorption Coefficient i.e. Koc value of test chemical 3-(bromomethyl)benzonitrile (CAS No. 28188-41-2) was estimated using EPI suite KOCWIN Program (v2.00) as 293.5 L/kg (log Koc= 2.4675) by means of MCI method at 25 deg. C. This log Koc value indicates that test chemical 3-(bromomethyl)benzonitrile has lmoderate sorption to soil and therefore have slow migration potential to ground water.

Additional information

Stability:

Hydrolysis:

Predicted data study for target chemical 3-(bromomethyl)benzonitrile (CAS no.28188-41-2) and experimental study for its structurally similar read across chemical is summarized below.

In a predicted data study the half life of hydrolysis of test chemical 3-(bromomethyl)benzonitrile was estimated by using HYDROWIN Program (v2.00) of EPI suite. The half life of hydrolysis of test chemical 3-(bromomethyl)benzonitrile was estimated to be 1.32 hrs.

Another supporting experimental study was done from authoritative database (HSDB, 2017) in this study the hydrolysis rate constant of structurally similar read across chemical 1-(bromomethyl)-3-methylbenzene (CAS no. 630-13-3) obtained was 0.000056 /sec and hydrolysis half life is 3.4 hrs at 20 oC for O isomer of read across chemical. Another hydrolysis rate constant value of read across chemical determined was 0.00256/sec and half life of hydrolysis is 4.3 mins at 25 oC for p isomer. Based on the half life of hydrolysis value at 25 oC it is concluded that this read across chemical is rapidly hydrolysabe.

On the basis of half life value determined by both the studies it is concluded that test chemical 3-(bromomethyl)benzonitrile is expected to be rapidly hydrolysable.

Biodegradation:

Biodegradation in water:

Two different predicted data studies for target chemical3-(bromomethyl)benzonitrile and experimental studies for its closest read across chemical with log Kow as primary descriptor have been studied for biodegradation in water endpoint and their results are summarized below.

In first weight of evidence study the Biodegradability of test chemical 3-(bromomethyl)benzonitrile was estimated by using OECD QSAR tool box v3.3 and eight closest read across chemicals with log Kow as primary descriptor. Percent biodegradation of test chemical 3-(bromomethyl)benzonitrile was estimated to be 9.1125 % by considering BOD as parameter and microorganisms as inoculum in 28 days. Based on the percent biodegradability it is concluded that this test chemical is not readily biodegradable.

In another weight of evidence study the Estimation Programs Interface Suite (EPI suite, 2017) was run to predict the biodegradation potential of the test compound 3-(bromomethyl)benzonitrile (CAS no. 28188 -41 -2) 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 3-(bromomethyl)benzonitrile is expected to be not readily biodegradable.

 

The supporting weight of evidence study was done from authoritative database (J Check, 2017) for read across chemical 1-(chloromethyl)-4-nitrobenzene (CAS no. 100-14-1) in this study the read across chemical was subjected to biodegradation test by taking sludge as inoculums at 30 mg/L concentration. Biodegradation was analysed by using BOD and HPLC parameters. The initial concentration of read across chemical was 100 mg/L. After 4 weeks (28 days)read across chemical1-(chloromethyl)-4-nitrobenzene showed 0.0% biodegradation by HPLC parameter and 51 % biodegradation by HPLC parameter using activated sludge as inoculum in 28 days. Based on percent biodegradability by BOD parameter it is concluded that this test chemical is not biodegradable.

 

Similarly another supporting experimental weight of study was done from same source as mentioned in above study (J check, 2017) for another read across chemical 1,2-dichloro-4-(chloromethyl)benzene (CAS no. 102-47-6) In this study the read across chemical was subjected to biodegradation test by taking sludge as inoculums at 30 mg/L concentration. Biodegradation was analysed by using BOD, TOC and GC parameters. The initial concentration of read across chemical was 100 mg/L. After 4 weeks (28 days) the read across chemical 1,2-dichloro-4-(chloromethyl)benzene showed 0.0% biodegradation by BOD and TOC parameter and 90 % biodegradation by GC parameter in 28 days. On the basis of percent biodegradation by BOD and TOC parameter it is concluded that test chemical 1,2-dichloro-4-(chloromethyl)benzene is not readily biodegradable.

On the basis of all the studies mentioned above biodegradation value by BOD parameter obtained was less than 10 % therefore it is concluded that target chemical 3-(bromomethyl)benzonitrile (CAS no. 28188 -41 -2) is expected to be not readily biodegradable in 28 days.

Biodegradation in water and sediments:

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound 3-(bromomethyl)benzonitrile (CAS no.28188 -41 -2) . If released in to the environment, 19.7 % 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 37.5 days (360 hrs). The half-life (37.5days 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 3-(bromomethyl)benzonitrile in sediment is estimated to be 337.5 days (8100 hrs). However, as the percentage release of test chemical into the sediment is less than 1% (i.e, reported as 0.327 %), indicates that test chemical 3-(bromomethyl)benzonitrile is not persistent in sediment as well.

Biodegradation in Soil:

The half-life period of test chemical 3-(bromomethyl)benzonitrile (CAS no.28188 -41 -2) 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, 77.2 % of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of test chemical 3-(bromomethyl)benzonitrile in soil is estimated to be 75 days (1800 hrs). Based on this half-life value of test chemical 3-(bromomethyl)benzonitrile, 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 predicted data studies for target chemical and two different experimental studies for its structurally similar read across chemicals have been conducted to determine bioaccumulation factor are summarized below.

The first weight of evidence study was done by using BCFBAF Program (v3.00) model of Estimation Program Interface (EPI suite 2017) In this study the bio concentration factor (BCF) for target chemical 3-(bromomethyl)benzonitrile (CAS No. 28188-41-2) was estimated to be 18.66 L/kg wet-wt at 25 deg. c.

 

Another weight of evidence study was done by using Bio-concentration Factor (v12.1.0.50374) module of Advanced Chemistry Development/I-lab predictive module (2017) in this study the Bio-concentration Factor at range pH 1-14  of the chemical 3-(bromomethyl)benzonitrile estimated to be 36.3 dimensionless.

Next weight of evidence study was done from SciFinder database of American Chemical Society (ACS, 2017) in this study the Bioconcentration factor (BCF) for test chemical 3-(bromomethyl)benzonitrile was predicted in aquatic organisms at pH 1-10 and temperature 25 °C .The Bioconcentration factor (BCF) of test substance 3-(bromomethyl)benzonitrile at pH 1-10 and temperature 25 °C was estimated to be 29.3 dimensionless.

 

Further the Bioconcentration factor (BCF) for test chemical 3-(bromomethyl)benzonitrile was predicted in aquatic organisms by Chemspider- ACD/PhysChem Suite of Royal Society of Chemistry (RCS, 2017) at pH 5.5 and pH 7.4.The Bioconcentration factor (BCF) of test substance 3-(bromomethyl)benzonitrile at pH 5.5 and pH 7.4 was estimated to be 46.82 dimensionless. 

Last predicted data study was done 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 3-(bromomethyl)benzonitrile was estimated to be 7.73 dimensionless . The predicted BCF result was based on the 5 OECD principles.

 

Next weight of evidence study was experimental study done from authoritative database (HSDB, 2017) for structurally similar read across chemical. The BCF value of read across chemical 1-(bromomethyl)-3-methylbenzene (CAS no. 620-13-3) estimated was 85 dimensionless by using log Kow of 3.43 and regression derived equation and it is far less than 2000 criteria so it is concluded that read across chemical 1-(bromomethyl)-3-methylbenzene is non bioaccumulative.

 

Similarly one more experimental study has been conducted from same source as mentioned in above study for another read across chemical. In this study the BCF value of read across 2-phenylacetonitrile (CAS no. 140-29-4) estimated was 9.0 dimensionless by using log Kow of 1.56 and regression derived equation and it is far less than 2000 criteria so it is concluded that read cross chemical 2-phenylacetonitrile is non bioaccumulative.

On the basis of above results for target chemical 3-(bromomethyl)benzonitrile (CAS No. 28188-41-2) (From EPI suite, ACD labs, Sci Finder database, CompTox Chemistry Dashboard and ChemSpider, 2017) it can be concluded that the BCF value of test substance 3-(bromomethyl)benzonitrile ranges from 7.73 to 46.82 dimensionless which does not exceed the bioconcentration threshold of 2000, indicating that the chemical 3-(bromomethyl)benzonitrile is not expected to bioaccumulate in the food chain.

Transport and Distribution:

Adsorption/desorption:

Various predicted data for the target compound of3-(bromomethyl)benzonitrile (CAS No. 28188-41-2)and supporting experimental weight of evidence studies for its structurally similar read across chemical were reviewed for the Adsorption end point are summarized as below.

In first weight of evidence study the Soil Adsorption Coefficient i.e. Koc value of test chemical 3-(bromomethyl)benzonitrile (CAS No. 28188-41-2) was estimated using Estimation Program Interface (EPI suite, 2017) KOCWIN Program (v2.00) as 293.5 L/kg (log Koc= 2.4675) by means of MCI method at 25 deg. C.

In another weight of evidence study the Soil Adsorption Coefficient i.e Koc value of test substance 3-(bromomethyl)benzonitrile (CAS no. 28188 -41 -2) was estimated using Adsorption Coefficient module (v12.1.0.50374) program of Advanced Chemistry Development /I-lab predictive module as Koc 456 dimensionless (log Koc= 2.6589).

 

Next weight of evidence study was done by using Sci Finder database of Ameriacn Chemical Socirty (ACS, 2017) in this study the soil adsorption co-efficient i.e.,  Koc value of test chemical 3-(bromomethyl)benzonitrile (CAS no. 28188 -41 -2) was estimated to be 391 ( log Koc =2.5921) at pH 1-10 at temperature 25 deg.C.

 

Further, by using Chemspider-ACD/Phy chem suite of Royal Society Of Chemistry (RCS, 2017) the soil adsorption co-efficient i.e., Koc value of test substance 3-(bromomethyl)benzonitrile (CAS no. 28188 -41 -2) was estimated to be 546.17 dimensionless (log Koc= 2.7373) at pH 5.5 and 7.4 and temperature 25 deg.C

 

Last predicted data study was 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 3-(bromomethyl)benzonitrile (CAS no. 28188 -41 -2) was estimated to be 130 L/kg (log Koc = 2.1139) .The predicted KOC result was based on the 5 OECD principles. Thus based on the result it is concluded that the test substance 3-(bromomethyl)benzonitrile has low sorption to soil and sediment and therefore have moderate migration potential to ground water.

 

Next weight of evidence study was experimental study done for structurally similar read across chemical from authoritative database (HSDB, 2017) in this study the Koc value for read across chemical 1-(bromomethyl)-3-methylbenzene (CAS no. 620-13-3) was determined by using a structure estimation method based on molecular connectivity indices. The estimated Koc value was 710 dimensionless and log Koc is 2.8512 this log Koc value suggests that  read across chemical 1-(bromomethyl)-3-methylbenzene is expected to have moderate sorption to soil and sediment and therefore has slow migration potential to ground water.

 

Last weight of evidence study was also experimental study for another read across chemical from same source as mentioned in above study (HSDB, 2017) in this study the Koc value for read across chemical 2-phenylacetonitrile (CAS no.140-29-4) was determined by using a log Kow of 1.56 and a regression-derived equation. The estimated Koc value was 170 dimensionless and log Koc is 2.2304 this log Koc value suggests that  read across chemical 2-phenylacetonitrile is expected to have low sorption to soil and sediment and therefore have moderate migration potential to ground water.

 

On the basis of above results for target chemical 3-(bromomethyl)benzonitrile(CAS No. 28188-41-2) (from EPI suite, ACD labs, Sci Finder database, Comptox chemistry dashboard and Chemspider 2017) and for its read across chemicals (From authoritative database HSDB) it can be concluded that the log Koc value of test chemical 3-(bromomethyl)benzonitrile ranges from 2.1139 to 2.7373 indicating that the chemical 3-(bromomethyl)benzonitrile has low to moderate sorption to soil and sediment and therefore it has moderate to slow migration potential to ground water.