7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one

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:

according to guideline

Guideline:

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

Principles of method if other than guideline:

The prediction was done by using OECD QSAR tool box v3.4

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material: 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one
- IUPAC name: 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one
- Molecular formula: C11H12O2
- Molecular weight: 176.214 g/mole
- Smiles : c12c(CCC(C1)=O)ccc(c2)OC
- Inchl: 1S/C11H12O2/c1-13-11-5-3-8-2-4-10(12)6-9(8)7-11/h3,5,7H,2,4,6H2,1H3
- Substance type: Organic
- Physical state: Liquid (Light yellow to yellow)

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: % degradation BOD

Value:

18.12

Sampling time:

28 d

Remarks on result:

other: other details not available

Details on results:

The test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one undergoes 18.11 % degradation by considering BOD as parameter 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" )  and "c" )  and "d" )  and "e" )  and "f" )  and "g" )  and "h" )  and "i" )  and ("j" and ( not "k") )  )  and "l" )  and ("m" and "n" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Nucleophilic addition AND Nucleophilic addition >> Addition to carbon-hetero double bonds AND Nucleophilic addition >> Addition to carbon-hetero double bonds >> Ketones by Protein binding by OASIS v1.4

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Class 1 (narcosis or baseline toxicity) by Acute aquatic toxicity classification by Verhaar (Modified)

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as days - weeks by Biodeg primary (Biowin 4) ONLY

Domain logical expression index: "d"

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

Domain logical expression index: "e"

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

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Does NOT Biodegrade Fast by Biodeg probability (Biowin 7) ONLY

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as No superfragment by Superfragments ONLY

Domain logical expression index: "h"

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

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Fast by Bioaccumulation - metabolism half-lives ONLY

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Not known precedent reproductive and developmental toxic potential by DART scheme v.1.0

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Known precedent reproductive and developmental toxic potential OR Piperazine-, dioxane-, morpholine-, tetrahydrothiopyran-like derivatives and cyclohexanamine (17c) by DART scheme v.1.0

Domain logical expression index: "l"

Similarity boundary:Target: COc1ccc2CCC(=O)Cc2c1
Threshold=20%,
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 >= 102 Da

Domain logical expression index: "n"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 187 Da

Validity criteria fulfilled:

not specified

Interpretation of results:

not readily biodegradable

Conclusions:

The test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one undergoes 18.11 % degradation by considering BOD as parameter and Microorganisms as inoculum in 28 days.

Executive summary:

Biodegradability of test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one (CAS no. 4133 -34 -0) is predicted by using OECD QSAR tool box v. 3.4 using log Kow as primary descriptor. The test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one undergoes 18.11 % degradation by considering BOD as parameter  and Microorganisms as inoculum in 28 days. Based on percent biodegradability it is concluded that test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one is not readily biodegradable.

Description of key information

Biodegradability of test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one (CAS no. 4133 -34 -0) is predicted by using OECD QSAR tool box v. 3.4 using log Kow as primary descriptor. The test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one undergoes 18.11 % degradation by considering BOD as parameter  and Microorganisms as inoculum in 28 days. Based on percent biodegradability it is concluded that test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one is not readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

Predicted data for target compound 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one (CAS no. 4133 -34 -0) and supporting weight of evidence studies for its closest read across chemicals with log Kow as a primary descriptor were reviewed for the biodegradation endpoint which are summarized as below.

In first weight of evidence study the Biodegradability of test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one (CAS no. 4133 -34 -0) was predicted by using OECD QSAR tool box v. 3.4 using log Kow as primary descriptor. The test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one undergoes 18.11 % degradation by considering BOD as parameter and Microorganisms as inoculums in 28 days. Based on percent biodegradability it is concluded that test chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one is not readily biodegradable.

Another prediction was done by using the Estimation Programs Interface Suite (EPI suite, 2017) to estimate the biodegradation potential of the test compound 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one 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 Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical  7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one is expected to be not readily biodegradable.

The supporting weight of evidence study done from authoritative database ( J check, 2017) in this study the Biodegradation experiment was carried out of read across chemical 1-Chloro-2,5-dimethoxybenzene (CAS no. 2100-42-7) by taking activated sludge as inoculums at 30 mg/L concentration . The initial concentration of read across chemical taken was 100 mg/L. Biodegradation was analyzed by using two parameters namely BOD and HPLC. The study design was of standard type. Percent biodegradation of read across chemical 1-Chloro-2,5-dimethoxybenzene was observed to be 0.0 % by both BOD and HPLC parameters in 28 days. Therefore it is concluded that read across chemical 1-Chloro-2,5-dimethoxybenzene is not readily biodegradable.

Similarly, another supporting weight of evidence study done from same source as mentioned above ( J check, 2017)in this study the Biodegradation experiment was carried out of read across chemical 1-chloro-2-[(1-chloropropan-2-yl)oxy]propane (CAS no.108-60-1) by taking activated sludge as inoculums at 30 mg/L concentration. The initial concentration of read across chemical taken was 100 mg/L. Biodegradation was analyzed by using three parameters namely BOD, TOC and GC. The study design was of improved type for volatile substance. Percent biodegradation of read across chemical 1-chloro-2-[(1-chloropropan-2-yl)oxy]propane was observed to be 0.0 % by BOD and GC parameters and 6.0 % by TOC parameter in 28 days. Therefore it is concluded that read across chemical 1-chloro-2-[(1-chloropropan-2-yl)oxy]propane is not readily biodegradable.

On the basis of above results for target chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one (CAS no. 4133 -34 -0) from EPI suite 2017 and OECD QSAR tool box v3.4, 2017 and for its read across substances (from authoritative database) the target chemical 7-methoxy-1,2,3,4-tetrahydronaphthalen-2-one can be expected to be not readily biodegradable.