2-octadecyl-1H-thioxantheno[2,1,9-def]isoquinoline-1,3(2H)-dione

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Justification for type of information:

QSAR prediction: migrated from IUCLID 5.6

Qualifier:

equivalent or similar to guideline

Guideline:

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

Principles of method if other than guideline:

Prediction is done using QSAR Toolbox version 3.3

GLP compliance:

not specified

Oxygen conditions:

not specified

Inoculum or test system:

other: microorganisms

Duration of test (contact time):

28 d

Parameter followed for biodegradation estimation:

other: BOD

Parameter:

other: BOD

Value:

0.167

Sampling time:

28 d

Remarks on result:

other: Other details not known.

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 ( not "f") )  )  and "g" )  and ("h" and "i" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Aryl AND Biphenyl AND Fused carbocyclic aromatic AND Fused saturated heterocycles AND Imide AND Naphtalene AND Quinolone/ Quinolinedione/ Isoquinolinedione AND Sulfide by Organic Functional groups

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Non-covalent interaction AND Non-covalent interaction >> DNA intercalation AND Non-covalent interaction >> DNA intercalation >> Polycyclic Aromatic Hydrocarbon and Naphthalenediimide Derivatives AND SN1 AND SN1 >> Alkylation after metabolically formed carbenium ion species AND SN1 >> Alkylation after metabolically formed carbenium ion species >> Polycyclic Aromatic Hydrocarbon and Naphthalenediimide Derivatives AND SN2 AND SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation AND SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation >> Polycyclic Aromatic Hydrocarbon and Naphthalenediimide Derivatives by DNA binding by OASIS v.1.4

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as SN1 AND SN1 >> Iminium Ion Formation AND SN1 >> Iminium Ion Formation >> Aliphatic tertiary amines by DNA binding by OECD

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Acylation AND Acylation >> Direct Acylation Involving a Leaving group AND Acylation >> Direct Acylation Involving a Leaving group >> Acetates by Protein binding by OECD

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Non binder, MW>500 by Estrogen Receptor Binding

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Moderate binder, NH2 group OR Non binder, impaired OH or NH2 group OR Non binder, non cyclic structure OR Non binder, without OH or NH2 group OR Strong binder, OH group OR Weak binder, NH2 group by Estrogen Receptor Binding

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Not calculated by Hydrolysis half-life (Kb, pH 8)(Hydrowin) ONLY

Domain logical expression index: "h"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 516 Da

Domain logical expression index: "i"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 630 Da

Validity criteria fulfilled:

not specified

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The test substance 2-Octadecyl-1H-thioxantheno(2,1,9-def)isoquinoline-1,3(2H)-dione is estimate to be not-readily biodegradable under test conditions.

Executive summary:

Biodegradation in water ability was predicted for the test substance 2-Octadecyl-1H-thioxantheno(2,1,9-def)isoquinoline-1,3(2H)-dione (CAS no. 27870 -92 -4) using the SSS QSAR prediction model. The ready biodegradability of the test substance 2-Octadecyl-1H-thioxantheno(2,1,9-def)

isoquinoline-1,3(2H)-dione was estimated as 0.166% in 28 days by using BOD parameter. This result indicates that 2-Octadecyl-1H-thioxantheno(2,1, 9 -def)isoquinoline-1, 3(2H)-dione was estimated to be not readily biodegradable in water.

Description of key information

Biodegradation in water ability was predicted (SSS QSAR Prediction model, 2016) for the test substance 2-Octadecyl-1H-thioxantheno(2,1,9-def)isoquinoline-1,3(2H)-dione (CAS no. 27870-92-4) using the SSS QSAR prediction model. The ready biodegradability of the test substance 2-Octadecyl-1H-thioxantheno(2,1,9-def)isoquinoline-1,3(2H)-dione was estimated as 0.166% in 28 days by using BOD parameter. This result indicates that 2-Octadecyl-1H-thioxantheno(2,1, 9 -def)isoquinoline-1, 3(2H)-dione was estimated to be not readily biodegradable in water. 

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

The predicted data for the test compound2-Octadecyl-1H-thioxantheno(2,1,9-def)isoquinoline-1,3(2H)-dione(CAS No. 27870-92-4) and the study for its read across substance were reviewed for the biodegradation end point which are summarized as below:

Biodegradation in water ability was predicted (SSS QSAR Prediction model, 2016) for the test substance 2-Octadecyl-1H-thioxantheno

(2,1,9-def)isoquinoline-1,3(2H)-dione (CAS no. 27870-92-4) using the SSS QSAR prediction model. The ready biodegradability of the test substance 2-Octadecyl-1H-thioxantheno(2,1,9-def)isoquinoline-1,3(2H)-dione was estimated as 0.166% in 28 days by using BOD parameter. This result indicates that 2-Octadecyl-1H-thioxantheno(2,1, 9 -def)isoquinoline-1, 3(2H)-dione was estimated to be not readily biodegradable in water.

 

Estimation Programs Interface Suite (EPI suite, 2016) was run to predict the biodegradation potential of the test compound 2-Octadecyl-1H- thioxantheno(2,1,9-def)isoquinoline-1,3(2H)-dione (CAS No. 27870 -92 -4). The screening test ready biodegradability of the substance was calculated using the software BIOWIN v4.10. The results indicate that 2-Octadecyl-1H-thioxantheno(2,1,9-def)isoquinoline-1,3(2H)- dione is not expected to be readily biodegradable in nature.

Biodegradation study was conducted for 15 days (K. YOSHIMURA et. al; 1980) for evaluating the percentage biodegradability of test substanceTri-n-octylamine. Biodegradation tests were carried out with an oxygen consumption measuring apparatus (Ohkura Coulometer) at 25°C. The basal medium was the JIS (Japanese Industrial Standards) BUD diluent prepared by adding 3 ml each of solution A, B, C and D to 987 ml of deionized water. The incubation chamber includes an incubation flask with a magnetic stirrer and a small vessel for carbon dioxide absorbent.Colorimetric, total organic carbon (TOC) and CO 2 production measurements. The colorimetric measurement was carried out according to Auerbach's method (Bromophenol Blue), whereas the TOC measurement was with a Beckman TOC analyzer.C02production was measured according to Ito's method. Activated sludge was obtained from a municipal sewage plant that treated domestic sewage in Tokyo. Concentration of inoculum i.e, activated sludge used was 30 mg/l and initial test substance conc. used in the study was 100 mg/l. The percentage degradation of test substance was found to be in the range of 0% by BOD/ThOD in 15 days. Thus, the substanceTri-n-octylamineis not expected to be readily biodegradable in water.

Biodegradation study was conducted (J-CHECK, 2016) for 14 days for evaluating the percentage biodegradability of test substance Tri-n-octylamine. Concentration of inoculum i.e; sludge used was 100 mg/l and initial test substance conc. used in the study was 30 mg/l. The percentage degradation of test substancewas found to be 0% by BOD and 12% by GC in 14 days. Thus, the substance Tri-n-octylamine is not expected to be readily biodegradable in water.

 

Biodegradation study was conducted for 14 days for evaluating the percentage biodegradability of test substanceTri-n-octylamine [Environmental Fate Data Base (EFDB), 2016]. Concentration of inoculum i.e; activated sludge used was 30 mg/l and intial test substance concentration used in the study was 100 mg/l. The percentage degradation of test substance was found to be in the range of 0-29% by BOD in 14 days at a temperature of 25°C and pH 7.0. Thus, the substance Tri-n-octylamineis not expected to be readily biodegradable in water.

 

On the basis of above results for target and read across substance, it can be concluded that the test substance 2-Octadecyl-1H-thioxantheno

(2,1,9-def)isoquinoline-1,3(2H)-dione can be expected to be not readily biodegradable in nature.