Pentyl formate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: screening tests

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Justification for type of information:

The supporting QMRF report has been attached

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

Principles of method if other than guideline:

The data is predicted using the OECD QSAR toolbox version 3.3 with logKow as the primary descriptor.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material: Pentyl formate
- Molecular formula: C6H12O2
- Molecular weight: 276.337 g/mol
- Smiles notation: C(COC=O)CCC
- InChl: 1S/C6H12O2/c1-2-3-4-5-8-6-7/h6H,2-5H2,1H3
- Substance type: Organic
- Physical state: Liquid

Oxygen conditions:

aerobic

Inoculum or test system:

other: Microorganisms

Duration of test (contact time):

28 d

Based on:

not specified

Parameter followed for biodegradation estimation:

other: BOD

Key result

Parameter:

other: BOD

Value:

88.4

Sampling time:

28 d

Remarks on result:

other: Other details not known

Details on results:

Test substance undergoes 88.4% degradation by BOD in 28 days.

The prediction was based on dataset comprised from the following descriptors: BOD
Estimation method: Takes average value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

((((((("a" or "b" or "c" or "d" or "e" )  and ("f" and ( not "g") )  )  and ("h" and ( not "i") )  )  and "j" )  and "k" )  and "l" )  and ("m" and "n" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Formic acid and formates by OECD HPV Chemical Categories

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Carboxylic acid ester by Organic Functional groups

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Carboxylic acid ester by Organic Functional groups (nested)

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] AND Aliphatic Carbon [-CH2-] AND Aliphatic Carbon [-CH3] AND Ester, aliphatic attach [-C(=O)O] AND Miscellaneous sulfide (=S) or oxide (=O) AND Olefinic carbon [=CH- or =C<] by Organic functional groups (US EPA)

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Carboxylic acid derivative AND Carboxylic acid ester by Organic functional groups, Norbert Haider (checkmol)

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as No alert found by DNA binding by OASIS v.1.3

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as AN2 OR AN2 >> Michael-type addition on alpha, beta-unsaturated carbonyl compounds OR AN2 >> Michael-type addition on alpha, beta-unsaturated carbonyl compounds >> Four- and Five-Membered Lactones OR AN2 >> Schiff base formation OR AN2 >> Schiff base formation >> Polarized Haloalkene Derivatives OR AN2 >> Shiff base formation after aldehyde release OR AN2 >> Shiff base formation after aldehyde release >> Specific Acetate Esters OR AN2 >> Shiff base formation for aldehydes OR AN2 >> Shiff base formation for aldehydes >> Haloalkane Derivatives with Labile Halogen OR AN2 >> Thioacylation via nucleophilic addition after cysteine-mediated thioketene formation OR AN2 >> Thioacylation via nucleophilic addition after cysteine-mediated thioketene formation >> Haloalkenes with Electron-Withdrawing Groups OR AN2 >> Thioacylation via nucleophilic addition after cysteine-mediated thioketene formation >> Polarized Haloalkene Derivatives OR Non-covalent interaction OR Non-covalent interaction >> DNA intercalation OR Non-covalent interaction >> DNA intercalation >> DNA Intercalators with Carboxamide Side Chain OR Radical OR Radical >> Generation of reactive oxygen species OR Radical >> Generation of reactive oxygen species >> Thiols OR Radical >> Radical mechanism by ROS formation (indirect) or direct radical attack on DNA OR Radical >> Radical mechanism by ROS formation (indirect) or direct radical attack on DNA >> Organic Peroxy Compounds OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitro Azoarenes OR SN1 OR SN1 >> Nucleophilic attack after carbenium ion formation OR SN1 >> Nucleophilic attack after carbenium ion formation >> Specific Acetate Esters OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitro Azoarenes OR SN2 OR SN2 >> Acylation OR SN2 >> Acylation >> Specific Acetate Esters OR SN2 >> Acylation involving a leaving group  OR SN2 >> Acylation involving a leaving group  >> Haloalkane Derivatives with Labile Halogen OR SN2 >> Alkylation, direct acting epoxides and related OR SN2 >> Alkylation, direct acting epoxides and related >> Epoxides and Aziridines OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation >> Haloalkenes with Electron-Withdrawing Groups OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom OR SN2 >> Alkylation, nucleophilic substitution at sp3-carbon atom >> Haloalkane Derivatives with Labile Halogen OR SN2 >> Alkylation, ring opening SN2 reaction OR SN2 >> Alkylation, ring opening SN2 reaction >> Four- and Five-Membered Lactones OR SN2 >> DNA alkylation OR SN2 >> DNA alkylation >> Alkylphosphates, Alkylthiophosphates and Alkylphosphonates OR SN2 >> Nucleophilic substitution at sp3 Carbon atom OR SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Specific Acetate Esters OR SN2 >> SN2 at sp3 and activated sp2 carbon atom OR SN2 >> SN2 at sp3 and activated sp2 carbon atom >> Polarized Haloalkene Derivatives by DNA binding by OASIS v.1.3

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Non binder, non cyclic structure by Estrogen Receptor Binding

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Non binder, impaired OH or NH2 group OR Non binder, MW>500 OR Non binder, without OH or NH2 group OR Strong binder, OH group by Estrogen Receptor Binding

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Esters by Acute aquatic toxicity MOA by OASIS ONLY

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Bioavailable by Lipinski Rule Oasis ONLY

Domain logical expression index: "l"

Similarity boundary:Target: CCCCCOC=O
Threshold=10%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "m"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 100 Da

Domain logical expression index: "n"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 200 Da

Validity criteria fulfilled:

not specified

Interpretation of results:

readily biodegradable

Conclusions:

The test chemical Pentyl formate was estimated to be readily biodegradable in water.

Executive summary:

Biodegradability of Pentyl formate (CAS no. 638 -49 -3) is predicted using OECD QSAR toolbox version 3.3 with logKow as the primary descriptor. Test substance undergoes 88.4% degradation by BOD in 28 days.Thus, based on percentage degradation, the test chemical Pentyl formate was estimated to be readily biodegradable in water.

Description of key information

Biodegradability of Pentyl formate (CAS no. 638 -49 -3) is predicted using OECD QSAR toolbox version 3.3 (2017) with logKow as the primary descriptor. Test substance undergoes 88.4% degradation by BOD in 28 days.Thus, based on percentage degradation, the test chemical Pentyl formate was estimated to be readily biodegradable in water.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

Various predicted data for the target compound Pentyl formate(CAS No. 638-49-3) 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 3.3 with logKow as the primary descriptor, percentage biodegradability of test chemical,Pentyl formate(CAS No. 638-49-3)was estimated. Test substance undergoes 88.4% degradation by BOD in 28 days.Thus, based on percentage degradation, the test chemical Pentyl formate was estimated to be readily biodegradable in water.

 

In another prediction using the Estimation Programs Interface Suite (EPI suite, 2017), the biodegradation potential of the test compoundPentyl formate(CAS No. 638-49-3)in the presence of mixed populations of environmental microorganisms was estimated. 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  Pentyl formate is expected to be readily biodegradable.

 

In a supporting weight of evidence study from peer reviewed journal (Kenneth S. Price et. al, 1974) for the read across chemical 1,3-dimethyl butyl acetate (CAS no. 108-84-9), biodegradation study was conducted for 20 days for evaluating the percentage biodegradability of read across substance1,3-dimethyl butyl acetate. Initial test substance conc. used in the study was 3, 7 and 10 mg/l, respectively. Domestic sewage, non-adapted 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. However, an oxygen meter that permitted correction for high salinity water was used for DO determinations where instrumental analysis was performed. 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 1,3-dimethyl butyl acetate was determined to be 11, 22, 52 and 67% degradation in 5, 10, 15 and 20 days, respectively. Thus, based on percentage degradation,1,3-dimethyl butyl acetate was considered to be readily biodegradable in nature.

 

Another biodegradation study was conducted for 14 days for evaluating the percentage biodegradability of read across substance sec-butyl acetate (CAS no. 105 -46 -4) (J-CHECK, 2017). 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 test substance formed acetic acid and sec-butanol in the test solution. The percentage degradation of substance sec-butyl acetate was determined to be 86, 94 and 100% by BOD, TOC removal and GC parameter in 14 days. Thus, based on percentage degradation, sec-butyl acetate is considered to be readily biodegradable in nature.

 

For another read across chemical 2-ethylhexyl acetate (CAS no. 103-09-3) from secondary source (OECD SIDS, 2010), biodegradation experiment was conducted for 28 days for evaluating the percentage biodegradability of read across substance 2 -ethylhexyl acetate. The study was performed according to OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test) under aerobic conditions. Municipal wastewater activated sludge was used as a test inoculum for the study. The percentage degradation of substance 2 -ethylhexyl acetate was determined to be 16, 49, 66 and 70% by CO2 evolution parameter in 3, 7, 12 and 28 days, respectively. Thus, based on percentage degradation, 2 -ethylhexyl acetate is considered to be readily biodegradable in nature.

 

On the basis of above results for target chemical Pentyl formate (from OECD QSAR toolbox version 3.3 and EPI suite, 2017) and for its read across substance (from peer reviewed journal, authoritative database J-CHECK and secondary source OECD SIDS), it can be concluded that the test substance Pentyl formatecan be expected to be readily biodegradable in nature.