Anisyl 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:

according 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: (4-methoxyphenyl)methyl formate
- Molecular formula: C9H10O3
- Molecular weight: 166.175 g/mol
- Smiles notation: c1(ccc(OC)cc1)COC=O
- InChl: 1S/C9H10O3/c1-11-9-4-2-8(3-5-9)6-12-7-10/h2-5,7H,6H2,1H3
- 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:

75

Sampling time:

28 d

Remarks on result:

other: Other details not known

Details on results:

Test substance undergoes 75% 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" )  and "e" )  and "f" )  and "g" )  and "h" )  and "i" )  and "j" )  and ("k" and "l" )  )

Domain logical expression index: "a"

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

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Alkylarylether OR Aromatic compound OR Carboxylic acid derivative OR Carboxylic acid ester OR Ether by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "c"

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

Domain logical expression index: "d"

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

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Not calculated by Biodeg BioHC half-life (Biowin) ONLY

Domain logical expression index: "f"

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

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Biodegrades Fast by Biodeg probability (Biowin 1) ONLY

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Biodegrades Fast by Biodeg probability (Biowin 2) ONLY

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Biodegrades Fast by Biodeg probability (Biowin 5) ONLY

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Biodegrades Fast by Biodeg probability (Biowin 7) ONLY

Domain logical expression index: "k"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 108 Da

Domain logical expression index: "l"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 343 Da

Validity criteria fulfilled:

not specified

Interpretation of results:

readily biodegradable

Conclusions:

The test chemical (4-methoxyphenyl)methyl formate was estimated to be readily biodegradable in water.

Executive summary:

Biodegradability of (4 -methoxyphenyl)methyl formate (CAS no. 122 -91 -8) is predicted using QSAR toolbox version 3.3 with logKow as the primary descriptor. Test substance undergoes 75% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical (4 -methoxyphenyl)methyl formate was estimated to be readily biodegradable in water.

Description of key information

Biodegradability of (4 -methoxyphenyl)methyl formate (CAS no. 122 -91 -8) is predicted using QSAR toolbox version 3.3 (2017) with logKow as the primary descriptor. Test substance undergoes 75% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical (4 -methoxyphenyl)methyl 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 (4-methoxyphenyl)methyl formate(CAS No. 122-91-8) and supporting weight of evidence studies 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 prediction done by SSS (2017) using OECD QSAR toolbox version 3.3 with logKow as the primary descriptor, percentage biodegradability of test chemical (4-methoxyphenyl)methyl formate(CAS No. 122-91-8) was estimated.Test substance undergoes 75% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical (4 -methoxyphenyl)methyl 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 compound(4-methoxyphenyl)methyl formate(CAS No. 122-91-8) 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 chemical (4-methoxyphenyl)methyl formate is expected to be readily biodegradable.

 

In a supporting weight of evidence study from authoritative database (J-CHECK, 2017) for the read across chemical 1,2-dimethoxybenzene (CAS no. 91-16-7), biodegradation experiment was conducted for 14 days for evaluating the percentage biodegradability of read across substance 1,2-dimethoxybenzene. 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 substance 1,2 -dimethoxybenzene was determined to be 95, 96 and 100% degradation by BOD, TOC removal and HPLC parameter in 14 days. Thus, based on percentage degradation, 1,2-dimethoxybenzene is considered to be readily biodegradable in nature.

 

Another biodegradation study was conducted for evaluating the percentage biodegradability of read across substance Ethoxybenzene (CAS no. 103-73-1) using an electrolytic respirometer (HSDB, 2017). The percentage degradation of substance ethoxybenzene was determined to be 52 -69% by BOD parameter after a lag of 6.25 days.  Thus, based on percentage degradation, ethoxybenzene is considered to be readily biodegradable in nature.

 

In a supporting weight of evidence study from peer reviewed journal (DEAN P. O'GRADY et. al, 1985) for read across substanceDiethyl phthalate (CAS no. 84-66-2), biodegradation experiment was conducted for evaluating the percentage biodegradability of read across substance Diethyl phthalate. The study was performed according to Semicontinuous activated sludge test (SCAS test) followed by a 19 day OECD Guideline 301 A (Ready Biodegradability: DOC Die Away Test), respectively. Acclimated activated sludge was used as a test inoculum. After the sludge was acclimated to the synthetic sewage feed and the dissolved organic carbon removal efficiency remained at >70%, test substance Diethyl phthalate and diethylene glycol feeding began, and then the draw-and fill procedure was maintained over a 3 -week period. Test chemical Diethyl phthalate was added to a single unit, using an acetone stock solution (<200 µl of acetone added) to provide a concentration of 1 mg/liter during week 1 and 3 mg/liter during weeks 2 and 3. After the 3 -week draw-and-fill period, the suspended solids in each of the two SCAS units were adjusted to 1,000 mg per unit (500 mg/liter). During the 3 -week draw-and-fill phase, 24 -h SCAS Diethyl phthalate biodegradation was determined once each week in the middle of the week by analyzing a 50 -ml aliquot from each unit after feeding of test chemical and synthetic sewage and after a 23 -h aeration period. Aeration was maintained and samples were taken on days 0, 1, 2, 3, 4, 5, 9, 12, 15, and 19 or until >90% degradation was observed on two consecutive sampling days. The extraction and analysis of chemical Diethyl phthalate was carried out. The difference in concentration for the two aliquots was reported as percent biodegradation. At the beginning of week 3, the single unit was split into two units and the 24-h biodegradation in each unit was determined in the middle of the week. Dissolved organic carbon was measured in all units including the diethylene glycol control. Standard addition of Diethyl phthalate to 50-ml portions of sludge and extraction and analysis demonstrated that the percent recoveries were high (mostly >90%). Diethyl phthalate was appeared to biodegrade fairly rapidly during the draw-and-fill phase of the experiment. The percentage degradation of substance Diethyl phthalate was determined to be greater than 94.8% by DOC removal parameter after a period of 24 hrs. Thus, based on percentage degradation, Diethyl phthalate is considered to be readily biodegradable in nature.

 

For the sameread across substance Diethyl phthalate (CAS no. 84-66-2) from secondary source (High Production Volume (HPV) Challenge Program, 2017), biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of read across substance Diethyl phthalate. The study was performed according to OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test) under aerobic conditions at a temperature of 22⁰C and pH of 7.0-7.2, respectively. Domestic sewage, soil and mineral medium was used as a test inoculum. Inoculum was aged for 2 weeks prior to test initiation. Initial test substance conc. used in the study was 20 mg/l. A glucose (at 20 mg/l) and blank was also tested during the study. 2L Erlenmeyer flasks were used as test vessels. The test chemical was added to flasks containing medium and inoculum. The flask were incubated and shaken in the dark for 28 days. Three replicates for CO2 evaluation and 4 replicates for primary degradation were tested. The CO2 production was captured in barium hydroxide solution. Primary biodegradation was determined at the beginning, middle and end by GC FID of entire contents of one replicate. A glucose and blank were also tested. The pH at initiation was 7.0 to 7.2. Test flasks were shaken at a rate of 120 rpm at 22 +/2 deg C. Primary degradation is expressed as the loss of initial test substance and Ultimate biodegradation is expressed as the percentage of ThC02 in each flask. The percentage degradation of substance Diethyl phthalate was determined to be 94.6% by theoretical CO2 evolution parameter in 28 days. Thus, based on percentage degradation, Diethyl phthalate is considered to be readily biodegradable in nature.

 

On the basis of above results for target chemical(4-methoxyphenyl)methyl formate(from OECD QSAR toolbox version 3.3 and EPI suite, 2017) and for its read across substance (from authoritative database J-CHECK, HSDB, peer reviewed journals and secondary source), it can be concluded that the test substance (4-methoxyphenyl)methyl formate can be expected to be readily biodegradable in nature.