Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-)

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: Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-)
- Molecular formula: C30H18FeN3O6.Na
- Molecular weight: 595.3222 g/mol
- Smiles notation: [Na+].[Fe+2].[O-]\N=C\1/C(=O)C=Cc2ccccc12.[O-]\N=C\3/C(=O)C=Cc4ccccc34.[O-]\N=C\5/C(=O)C=Cc6ccccc56
- InChI: 1S/3C10H7NO2.Fe.Na/c3*12-9-6-5-7-3-1-2-4-8(7)10(9)11-13;;/h3*1-6,13H;;/q;;;+2;+1/p-3/b3*11-10-;;
- Substance type: Organic
- Physical state: Solid

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:

19.6

Sampling time:

28 d

Remarks on result:

other: Other details not known

Details on results:

Test substance undergoes 19.6% 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" )  and "c" )  and "d" )  and ("e" and "f" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Michael Addition OR Michael Addition >> Quinoide type compounds OR Michael Addition >> Quinoide type compounds >> Quinone methide(s)/imines; Quinoide oxime structure; Nitroquinones, Naphthoquinone(s)/imines  by Protein binding by OASIS v1.3

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Michael addition OR Michael addition >> Polarised Alkenes OR Michael addition >> Polarised Alkenes >> Polarised alkene - ketones OR Michael addition >> Quinones and Quinone-type Chemicals OR Michael addition >> Quinones and Quinone-type Chemicals >> Quinone-imine by Protein binding by OECD

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Not bioavailable by Lipinski Rule Oasis ONLY

Domain logical expression index: "d"

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

Domain logical expression index: "e"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 315 Da

Domain logical expression index: "f"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 605 Da

Validity criteria fulfilled:

not specified

Interpretation of results:

not readily biodegradable

Conclusions:

The test chemical Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) was estimated to be not readily biodegradable in water.

Executive summary:

Biodegradability of Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) (CAS no. 16143-80-9) is predicted using OECD QSAR toolbox version 3.3 with logKow as the primary descriptor. Test substance undergoes 19.6% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) was estimated to be not readily biodegradable in water.

Description of key information

Biodegradability of Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) (CAS no. 16143-80-9) is predicted using OECD QSAR toolbox version 3.3 (2017) with logKow as the primary descriptor. Test substance undergoes 19.6% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) 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

Predicted data for the target compound Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) (CAS No. 16143-80-9) and various supporting weight of evidence studies for its read across substance 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, Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-)(CAS No. 16143-80-9)was estimated.Test substance undergoes 19.6% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) was estimated to be not readily biodegradable in water.

 

In a supporting weight of evidence study from peer reviewed journal (U. Pagga and O. Brown, 1986) for the read across chemical1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-((4-sulfo-1-naphthalenyl)azo)-, trisodium salt (CAS no. 2611-82-7),biodegradation experiment was carried out for 48 days for evaluating the percentage biodegradation of the read across chemical 1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-((4-sulfo-1-naphthalenyl)azo)-, trisodium salt using modified OECD Guideline 302B. Activated sludge was used as a test inoculum. The sources of the activated sludge were treatment plants conveniently located to the laboratories carrying out the test. These treatment plants received communal and/or industrial wastewater. Concentration of inoculum i.e, activated sludge used was 0.5 g/l and initial test substance conc. used in the study was 100 mg/l. Analytical methods involve the measurement of extinction at absorption maximum 412 nm and DOC (dissolved organic carbon).The percentage degradation of substance 1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-((4-sulfo-1-naphthalenyl)azo)-, trisodium salt was determined to be 5% by DOC removal. Based on the limit values for classification of Static Test – the test chemical was classified in CATEGORY ‘D’. Thus, the substance 1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-((4-sulfo-1-naphthalenyl)azo)-, trisodium salt is considered to be not readily biodegradable in nature.

 

For the same read across chemical1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-((4-sulfo-1-naphthalenyl)azo)-, trisodium salt (CAS no. 2611-82-7), biodegradation study was conducted for evaluating the percentage biodegradability of read across substance 1,3 -Naphthalenedisulfonic acid, 7 -hydroxy-8 -((4 -sulfo-1 -naphthalenyl)azo)-, trisodium salt (Toshihide Saito et. al, 1984). Activated sludge was used as a test inoculum obtained from municipal sewage. Test substance of conc. 500 mg/l was prepared and diluted as needed. The COD measurement was performed by the potassium dichromate reflux method based on Japanese Industrial Standards. In the BOD measurement, a sample solution was taken into a container. Then JIS-BOD testing solutions, i.e. 3 ml of A solution and 1 ml of B, C, D solutions were added to the sample solution, respectively. Then 5 ml of the supernatant of the municipal sewage activated sludge was added to the sample solution and diluted to 300 ml with water. Immediately, the BOD-time curve was recorded at 20~ using an Ohkura OM-200I type coulometer. The TOC measurement was carried out by a Yanagimoto TOC-ILW.BOD5, COD, ThOD and TOC value of the test chemical 1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-((4-sulfo-1-naphthalenyl)azo)-, trisodium salt was determined to be 0.021, 0.65, 1.23 and 0.20 g/g, respectively. The BOD5/TOC ratio of chemical 1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-((4-sulfo-1-naphthalenyl)azo)-, trisodium salt was determined to be 0.11 (i.e. ranges in between 0.08-0.89), indicating that the chemical is highly resistant to aerobic biodegradation. Thus, based on this value BOD5/TOC value, it can be concluded that the chemical 1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-((4-sulfo-1-naphthalenyl)azo)-, trisodium salt is not readily biodegradable in nature.

 

In an another supporting weight of evidence study from authoritative database (J-CHECK, 2017), biodegradation experiment was conducted for 14 days for evaluating the percentage biodegradability of read across substance 2,4 -di-tert-butyl-6 -(5 -chloro-2H-benzotriazol-2 -yl)phenol (CAS no.3864 -99 -1). 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 2,4 -di-tert-butyl-6 -(5 -chloro-2H-benzotriazol-2 -yl)phenol was determined to be 0 and 1% by BOD and GC parameter in 14 days. Thus, based on percentage degradation, 2,4 -di-tert-butyl-6 -(5 -chloro-2H-benzotriazol-2 -yl)phenol is considered to be not readily biodegradable in nature.

 

Another biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of read across substance 2 -tert-butyl-6 -(5 -chloro-2H-benzotriazol-2 -yl)-4 -methylphenol (CAS no. 3896 -11 -5) (OECD SIDS, 2009). The study was performed according to OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I)) and other guideline “Biodegradability study of Chemical Substances by Microorganisms; Testing Methods relating New Chemical Substances" under aerobic conditions at a temperature of 25 +/-1°C, respectively. Mixture of sewage, soil and natural water was used as a test inoculum for the study. Sludge from four sewage treatment plants, surface water and shoreline soil (which was in contact with the atmosphere) from three rivers, one lake and two marine sites was collected. 500 mL of each of the filtrate of the activated sludge collected from the sites described above and 5 L of the filtrate of the old activated sludge used for the study until that time was mixed to obtain 10 L of mixture. The pH was adjusted to 7.0+/-1.0 and aerated in a culture tank. Approximately 30 minutes after aeration ceased, approximately 1/3 of the total volume was removed and replace with dechlorinated water. The mixture was re-aerated and synthetic sewage added so that the concentration of supernatant exchange fluid was set to 0.1%. Initial test substance conc. used in the study was 100 mg/l, respectively. Analytical methods used for the study was HPLC. Aniline was used as a reference substance for the study. The percentage degradation of substance 2 -tert-butyl-6 -(5 -chloro-2H-benzotriazol-2 -yl)-4 -methylphenol was determined to be 0% by O2 consumption and test mat. analysis parameter in 28 days, respectively. Percentage degradation of aniline after 7 and 14 days obtained by BOD were 64 % and 76 % respectively, confirming the validity of the study. Thus, based on percentage degradation, 2 -tert-butyl-6 -(5 -chloro-2H-benzotriazol-2 -yl)-4 -methylphenol is considered to be not readily biodegradable in nature.

 

On the basis of above results for target chemicalSodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-)(from OECD QSAR toolbox version 3.3, 2017) and for its read across substance (from peer reviewed journals, authoritative database J-CHECK and secondary source OECD SIDS), it can be concluded that the test substance Sodium tris(1,2-naphthoquinone 1-oximato-O,O')ferrate(1-) can be expected to be not readily biodegradable in nature.