Pentene, 2,4,4-trimethyl-, sulfurized

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 (as cited in study report): Pentene, 2,4,4-trimethyl-, sulfurized
- Molecular formula :C24H50S8
- Molecular weight: 595.144 g/mol
- Substance type: Organic
- Physical state: Liquid

Oxygen conditions:

aerobic

Inoculum or test system:

other: Microorganisms

Duration of test (contact time):

28 d

Parameter followed for biodegradation estimation:

other: BOD

Key result

Parameter:

other: BOD

Value:

24.6

Sampling time:

28 d

Remarks on result:

other: Other details not known

Details on results:

Test substance undergoes 24.6% 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 "g" )  and "h" )  and ("i" and ( not "j") )  )  and "k" )  and ("l" and "m" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Alkane branched with quaternary carbon OR Sulfide, poly OR tert-Butyl by Organic Functional groups ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Alkane branched with quaternary carbon OR Overlapping groups OR Sulfide, poly OR tert-Butyl by Organic Functional groups (nested) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Alkane branched with quaternary carbon OR Overlapping groups OR Sulfide, poly OR tert-Butyl by Organic Functional groups (nested) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] OR Aliphatic Carbon [-CH2-] OR Aliphatic Carbon [-CH3] OR Disulfide [-SS-] OR Suflur, di- or poly suflur attach [S] OR Tertiary Carbon by Organic functional groups (US EPA) ONLY

Domain logical expression index: "e"

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

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Does NOT Biodegrade Fast by Biodeg probability (Biowin 2) ONLY

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Does NOT Biodegrade Fast by Biodeg probability (Biowin 5) ONLY

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Does NOT Biodegrade Fast by Biodeg probability (Biowin 6) ONLY

Domain logical expression index: "i"

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

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as AN2 OR AN2 >> Schiff base formation by aldehyde formed after metabolic activation OR AN2 >> Schiff base formation by aldehyde formed after metabolic activation >> Geminal Polyhaloalkane Derivatives OR AN2 >> Shiff base formation for aldehydes OR AN2 >> Shiff base formation for aldehydes >> Geminal Polyhaloalkane Derivatives OR Radical OR Radical >> Generation of ROS by glutathione depletion (indirect) OR Radical >> Generation of ROS by glutathione depletion (indirect) >> Haloalkanes Containing Heteroatom OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Geminal Polyhaloalkane Derivatives OR SN2 OR SN2 >> Acylation involving a leaving group  OR SN2 >> Acylation involving a leaving group  >> Geminal Polyhaloalkane Derivatives OR SN2 >> Acylation involving a leaving group after metabolic activation OR SN2 >> Acylation involving a leaving group after metabolic activation >> Geminal Polyhaloalkane Derivatives OR SN2 >> Alkylation, direct acting epoxides and related OR SN2 >> Alkylation, direct acting epoxides and related >> Epoxides and Aziridines OR SN2 >> DNA alkylation OR SN2 >> DNA alkylation >> Vicinal Dihaloalkanes OR SN2 >> Internal SN2 reaction with aziridinium and/or cyclic sulfonium ion formation (enzymatic) OR SN2 >> Internal SN2 reaction with aziridinium and/or cyclic sulfonium ion formation (enzymatic) >> Vicinal Dihaloalkanes OR SN2 >> Nucleophilic substitution at sp3 Carbon atom OR SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Haloalkanes Containing Heteroatom OR SN2 >> Nucleophilic substitution at sp3 carbon atom after thiol (glutathione) conjugation OR SN2 >> Nucleophilic substitution at sp3 carbon atom after thiol (glutathione) conjugation >> Geminal Polyhaloalkane Derivatives by DNA binding by OASIS v.1.3

Domain logical expression index: "k"

Similarity boundary:Target: CC(C)(C)CC(C)(C)SSSSCC(C)(CC(C)(C)C)SSSSC(C)(C)CC(C)(C)C
Threshold=50%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "l"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 280 Da

Domain logical expression index: "m"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 635 Da

Validity criteria fulfilled:

not specified

Interpretation of results:

inherently biodegradable

Conclusions:

The test chemical Pentene, 2,4,4-trimethyl-, sulfurized was estimated to be not readily biodegradable in water.

Executive summary:

Biodegradability of Pentene, 2,4,4-trimethyl-, sulfurized (CAS no. 68515 -88 -8) is predicted using QSAR toolbox version 3.3 with logKow as the primary descriptor. Test substance undergoes 24.6% degradation by BOD in 28 days.Thus, based on percentage degradation, the test chemical Pentene, 2,4,4 -trimethyl-, sulfurized was estimated to be not readily biodegradable in water. But as the percentage degradation of the chemical is greater than 20% (i.e reported as 24.6%), chemical can be considered as inherently biodegradable in nature.

Description of key information

Biodegradability of Pentene, 2,4,4-trimethyl-, sulfurized (CAS no. 68515 -88 -8) is predicted using QSAR toolbox version 3.3 with logKow as the primary descriptor (2017). Test substance undergoes 24.6% degradation by BOD in 28 days.Thus, based on percentage degradation, the test chemical Pentene, 2,4,4 -trimethyl-, sulfurized was estimated to be not readily biodegradable in water. But as the percentage degradation of the chemical is greater than 20% (i.e reported as 24.6%), chemical can be considered as inherently biodegradable in nature.

Key value for chemical safety assessment

Biodegradation in water:

inherently biodegradable

Additional information

2 predicted data for the target compound Pentene, 2,4,4-trimethyl-, sulfurized (CAS no. 68515-88-8) and the total 2 weight of evidence studies (from authoritative database) for its closest read across substance with logKow as the primary descriptor were reviewed for the biodegradation end point which are summarized as below:

 

In a predicted data done by SSS (2017) using QSAR toolbox version 3.3 with logKow as the primary descriptor, percentage biodegradability of test chemical 4 Pentene, 2,4,4-trimethyl-, sulfurized (CAS no. 68515-88-8) was estimated. Test substance undergoes 24.6% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical Pentene, 2,4,4 -trimethyl-, sulfurized was estimated to be not readily biodegradable in water. But as the percentage degradation of the chemical is greater than 20% (i.e reported as 24.6%), chemical can be considered as inherently biodegradable in nature.

 

In another prediction using the Estimation Programs Interface Suite (EPI suite, 2017), the biodegradation potential of the test compound Pentene, 2,4,4-trimethyl-, sulfurized (CAS no. 68515-88-8) 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 Pentene, 2,4,4 -trimethyl-, sulfurized is expected to be not readily biodegradable.

 

Biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of read across substance tridodecyl trithiophosphite (CAS no. 1656 -63 -9) (J-CHECK, 2016). 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 test substance was determined to be 0% and 23% by BOD and GC parameter in 28 days. Thus, based on percentage degradation, tridodecyl trithiophosphite is considered to be not readily biodegradable in nature. But as the percentage degradation of the chemical is greater than 20% (i.e reported as 23% by GC parameter), chemical can be considered as inherently biodegradable in nature.

 

Another supporting weight of evidence study of biodegradation was conducted for 28 days for evaluating the percentage biodegradability of read across substance 2,6,10,15,19,23 -hexamethyltetracosane (CAS no. 111 -01 -3) (J-CHECK, 2016). 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 test substance was determined to be 36% and 51% by BOD and GC parameter in 28 days. Thus, based on percentage degradation, 2,6,10,15,19,23 -hexamethyltetracosane is considered to be not readily biodegradable in water. But as the percentage degradation of the chemical is greater than 20% (i.e reported as 36% and 51%), chemical can be considered as inherently biodegradable in nature.

 

On the basis of above results for target chemicalPentene, 2,4,4-trimethyl-, sulfurized (from OECD QSAR toolbox version 3.3 and EPI Suite) and for its read across substance (from authoritative database J-CHECK), it can be concluded that the test substance Pentene, 2,4,4-trimethyl-, sulfurized can be expected to be inherently biodegradable in nature.