p-tolyl acetate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Justification for type of information:

Data is from authoritative database

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Principles of method if other than guideline:

Biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of test substance p-tolyl acetate. The study was performed according to OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test).

GLP compliance:

not specified

Specific details on test material used for the study:

CAS number: 140-39-6
EC number: 205-413-1
- Name of test material (as cited in study report): 4-methylphenyl acetate
- Molecular formula (if other than submission substance): C9H10O2
- Molecular weight (if other than submission substance): 150.176 g/mol
- Smiles notation (if other than submission substance): c1(ccc(C)cc1)OC(C)=O
- InChI: 1S/C9H10O2/c1-7-3-5-9(6-4-7)11-8(2)10/h3-6H,1-2H3
- Substance type: Organic
- Physical state: Liquid

Oxygen conditions:

aerobic

Inoculum or test system:

not specified

Duration of test (contact time):

28 d

Parameter followed for biodegradation estimation:

other: BOD and ThOD

Key result

Parameter:

other: % degradation as per BOD and ThOD

Value:

84

Sampling time:

28 d

Remarks on result:

other: Other details not known

Details on results:

Test substance undergoes 84% degradation by BOD and ThOD parameter in 28 days.

Validity criteria fulfilled:

not specified

Interpretation of results:

readily biodegradable

Conclusions:

The percentage degradation of test substance was determined to 84% degradation by BOD and ThOD parameter in 28 days. Thus, based on percentage degradation, p-tolyl acetate is considered to be readily biodegradable in water.

Executive summary:

Biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of test substance p-tolyl acetate. The study was performed according to OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test) under aerobic conditions.The percentage degradation of test substance was determined to 84% degradation by BOD and ThOD parameter in 28 days. Thus, based on percentage degradation, p-tolyl acetate is considered to be readily biodegradable in nature.

Description of key information

Biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of test substance p-tolyl acetate (CAS no. 140-39-6) (GSBL database, 2016). The study was performed according to OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test) under aerobic conditions. The percentage degradation of test substance was determined to 84% degradation by BOD and ThOD parameter in 28 days. Thus, based on percentage degradation, p-tolyl acetate is considered to be readily biodegradable in nature.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

In different studies, p-tolyl acetate has been investigated for potential for biodegradation to a greater or lesser extent. These incude 1 experimental study from authoritative database along with 2 predicted data for the target compound p-tolyl acetate (CAS no. 140 -39 -6) and the 3 studies (from authoritative database) for its closest read across substance with logKow as the primary descriptor.

 

In a study from authoritative database(GSBL database, 2016) for target chemical p-tolyl acetate (CAS No. 140 -39 -6), biodegradation experiment was conducted for 28 days for evaluating the percentage biodegradability of test substance p-tolyl acetate. The study was performed according to OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test) under aerobic conditions. The percentage degradation of test substance was determined to 84% degradation by BOD and ThOD parameter in 28 days. Thus, based on percentage degradation, p-tolyl acetate is considered to be readily biodegradable in nature.

 

In another prediction for target chemical p-tolyl acetate(CAS No. 140-39-6) done using QSAR toolbox version 3.4 (2017), the test substance undergoes 69.5% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical p-tolyl acetate was estimated to be readily biodegradable in water.

 

Additional supporting data of biodegradation for target chemical p-tolyl acetate(CAS No. 140-39-6) is predicted using Estimation Programs Interface Suite (EPI suite, 2017) 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 p-tolyl acetate is expected to be readily biodegradable.

 

In a study reported for read across substance o-acetylsalicylic acid (CAS no. 50-78-2)which is having a percentage similarity of 50-60% with the target chemical p-tolyl acetate(J-CHECK, 2016), experiment was conducted for 28 days for evaluating the percentage biodegradability. Concentration of inoculum i.e, sludge used was 30 mg/l and initial substance conc. used in the study was 100 mg/l, respectively. At the beginning of the test, the pH of the test solution was adjusted. The percentage degradation of read across substance was determined to be 86, 97 and 100% degradation by BOD, TOC removal and HPLC parameter in 28 days. The read across substance was hydrolyzed to form Salicylic acid and Acetic acid in (Water + Test Substance) systems. Thus, based on percentage degradation, o-acetylsalicylic acid is considered to be readily biodegradable in nature.

 

In an additional study of read across substance Methyl acetoacetate (CAS no. 105-45-3) from authoritative database (J-CHECK, 2016), experiment was carried out for 14 days for evaluating the percentage biodegradability of the substance. Concentration of inoculum i.e, sludge used was 30 mg/l and initial substance conc. used in the study was 100 mg/l, respectively. The percentage degradation of read across substance was determined to be 78, 98 and 100% degradation by BOD, TOC removal and HPLC parameter in 14 days. Thus, based on percentage degradation, Methyl acetoacetate is considered to be readily biodegradable in nature.

 

Another biodegradation study was conducted for 28 days for read across substance Methyl acetoacetate (CAS no. 105-45-3) (HSDB, 2016). The study was performed according to OECD Guideline 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test). The percentage degradation of read across substance was determined to >90% degradation in 2 days. Thus, based on percentage degradation, Methyl acetoacetate is considered to be readily biodegradable in nature.

 

On the basis of above results for target chemical p-tolyl acetate(from gsbl authoritative database, OECD QSAR toolbox version 3.4 and EPI Suite) and for its read across substance (from authoritative database J-CHECK and HSDB), it can be concluded that the test substance p-tolyl acetate can be expected to be readily biodegradable in nature.