Dialuminium tris[2-(2,4,5,7-tetrabromo-6-oxido-3-oxoxanthen-9-yl)benzoate]

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)

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:

Prediction is done using OECD QSAR Toolbox version 3.4 with logKow as the primary descriptor.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material (as cited in study report):Di aluminium tris [2-(2,4,5,7-tetrabromo-6-oxido-3-oxoxanthen-9-yl)benzoate]
- Molecular formula :C20H8Br4O5.2/3Al
- Molecular weight :1991.5992 g/mol
- InChl :1S/3C20H8Br4O5.2Al/c3*21-11-5-9-17(13(23)15(11)25)28-18-10(6-12(22)16(26)14(18)24)20(9)8-4-2-1-3-7(8)19(27)29-20;;/h3*1-6,25-26H;;/q;;;2*+3/p-6
- Substance type:Organic
- Physical state:Solid

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: BOD

Value:

6.4

Sampling time:

28 d

Remarks on result:

other: Other details not known.

Details on results:

Test substance Di aluminium tris [2-(2,4,5,7-tetrabromo-6-oxido-3-oxoxanthen-9-yl)benzoate] undegoes 6.4% degradation by BOD 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" or "c" )  and "d" )  and ("e" and ( not "f") )  )  and ("g" and ( not "h") )  )  and ("i" and "j" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Phenolphthaleins AND Phenols (Acute toxicity) AND Phenols (Chronic toxicity) by US-EPA New Chemical Categories

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Phenols (Chronic toxicity) by US-EPA New Chemical Categories

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as AN2 AND AN2 >> Michael-type addition to quinoid structures  AND AN2 >> Michael-type addition to quinoid structures  >> Substituted Phenols by Protein binding by OASIS v1.4

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Does NOT Biodegrade Fast by Biodeg probability (Biowin 2) ONLY

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, OH grooup OR Non binder, impaired OH or NH2 group OR Strong binder, OH group OR Very strong binder, OH group OR Weak binder, OH group by Estrogen Receptor Binding

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Halogens AND Non-Metals by Groups of elements

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Alkali Earth by Groups of elements

Domain logical expression index: "i"

Parametric boundary:The target chemical should have a value of Molecular weight which is >= 531 Da

Domain logical expression index: "j"

Parametric boundary:The target chemical should have a value of Molecular weight which is <= 784 Da

Validity criteria fulfilled:

not specified

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The test chemical Dialuminium tris(2-(2,4,5,7-tetrabromo-6-oxido-3-oxoxanthen-9-yl)benzoate) was estimated to be not readily biodegradable in water.

Executive summary:

Biodegradability of Dialuminium tris(2-(2,4,5,7-tetrabromo-6-oxido-3-oxoxanthen-9-yl)benzoate) is predicted using OECD QSAR toolbox version 3.4 with logKow as the primary descriptor (2017). Test substance undegoes 6.4% degradation by BOD parameter and microrganisms as inoculum in 28 days.The test chemical Di aluminium  tris [2-(2,4,5,7-tetrabromo-6-oxido-3-oxoxanthen-9-yl)benzoate] was estimated to be not readily biodegradable in water.

Description of key information

Biodegradability of Dialuminium tris(2-(2,4,5,7-tetrabromo-6-oxido-3-oxoxanthen-9-yl)benzoate) is predicted using QSAR toolbox version 3.4 with log Kow as the primary descriptor (2017). Test substance undegoes 6.4% degradation by BOD in 28 days.The test chemical Dialuminium tris(2 -(2,4,5,7 -tetrabromo-6 -oxido-3 -oxoxanthen-9 -yl)benzoate) 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 target and various study of its read across substance were reviewed for the biodegradation end point which are summarized as below:

Biodegradability of target chemical Dialuminium tris(2-(2,4,5,7-tetrabromo-6-oxido-3-oxoxanthen-9-yl)benzoate) (CAS no. 15876 -39 -8) is predicted using QSAR toolbox version 3.4 with logKow as the primary descriptor (2017). Test substance undegoes 6.4% degradation by BOD in 28 days.The test chemical Dialuminium tris(2 -(2,4,5,7 -tetrabromo-6 -oxido-3 -oxoxanthen-9 -yl)benzoate) was estimated to be not readily biodegradable in water.

In a weight of evidence study from peer reviewed journal (U. Pagga and O. Brown, 1986), aerobic degradation of Eosim (CAS no. 17372 -87 -1) was studied (U. Pagga and O. Brown, 1986) by a modification of the OECD Guideline 302B used as the static test method. The main variations from the OECD method were the extension of the test period from 28 to 42 days and, because the test time was relatively long, the weekly feeding of the sludge by most of the participating laboratories. The sources of the activated sludge were treatment plants conveniently located to the laboratories carrying out the test. Each week 100 mg/l of yeast extract was used for the feeding of the test inoculum. Conc. of the test chemical and inoculum used for the study was 100 mg/l and 0.5g/l, respectively. Detection method involve the determination of extinction at absorption maximum of 412 nm and DOC (dissolved organic carbon). The DOC elimination of the test chemical was found to be -3% after 42 days. Based on the criteria for evaluation of the static test results, Acid red 87 was in Category D, which signifies that the test chemical was found to not readily biodegradable in nature at the end of 42 days.

For the same read across chemical Eosin (CAS no. 17372 -87 -1), Degradation of test chemical Eosin was studied (Laura Carmen Apostol et. al; 2012) using non-acclimated anaerobic granular sludge under anaerobic conditions. Non-acclimated anaerobic granular sludge was collected from wastewater treatment plant of ‘‘Central de Cervejas’’, Vialonga, Portugal. The volatile suspended solids content of the biomass was determined as 0.0943 g VSS g^-1. Eosin Y was screened for biodegradation using an anaerobic granular biomass. The biomass, 0.94g/l VSS (Volatile suspended solids), the substrate and macronutrients in a total volume of 50 ml of medium, that was buffered at a pH of 7 ± 0.2 with NaHCO₃(2.5 g L-1). As macronutrients, 2.8 g/L NH₄Cl, 2.5 g/L; KH₂PO₄, 1 g/L MgSO₄.7H₂O and 0.06 g/L CaCl₂were added. Volatile fatty acids (VFAs: acetic, propionic, and butyric acid, 1:10:10) were supplemented as electron source for the reduction (2 g COD L-¹). After the pre-incubation period, the dye was added with a syringe from the stock solution to a final concentration of 0.3mM. After the pre-incubation period, the dye was added with a syringe from the stock solution to a final concentration of 0.3 mM. The serum bottles were further incubated at 37°C in a rotary shaker at 120 rpm, for 1 day. All the experiments were prepared in triplicate. For the anaerobic biological dye degradation, batch assays were performed in the same conditions as the dye degradation assay. The effect of biomass concentration on decolorization was evaluated. Biomass concentrations (0.94, 1.89, 3.77, and 4.71 g/l VSS) were assayed. Color decrease was monitored spectrophotometricaly in a 96-well plate reader . Compounds were eluted at a flow rate of 0.7 ml/ min and at room temperature, with a linear gradient of mobile phase from 10 to 100 % of solvent A, over 15 min, followed by isocratic condition with 100 % of solvent A over 10 min. Compounds elution was monitored at λmax of the dye and 230 nm. Samples were withdrawn (300 µL), at select intervals, samples were centrifuged at 5000 rpm for 10 min to remove the biomass and diluted, with the same buffer as of the reaction, to obtain less than one absorbance unit (AU), due to the high absorbance of the dye, even at low concentrations biomass. The decolorization (%) of Eosin B was merely 7% in the screening assay.

In a weight of evidence of another read across chemical Phoxine B (CAS no. 18472 -87 -2), the biodegradability of phloxine B was studied (Yasuhide TONOGAI et. al; 1978) using methods: Aerobic degradability, Warburg method and BOD measurement. Return activated sludge was obtained from the municipal sewage treatment plant, Nakahama, Osaka. Synthetic sewage preparation: Glucose peptone and potassium dihydrogen phosphate, 30g each, were dissolved in 1 liter water and the pH was adjusted to pH 7.0 with sodium hydroxide. Seeded Dilution water: To 1 liter, 10 ml of supernatant of sludge was added. Aerobic biodegradation assay: To 750ml of sludge (MLSS ca, 3,000 ppm) 250 ml of O.03 M dye solution was added, and bubbled with air sufficiently at 20°C. 5ml sample was taken out once a day. After sampling 5ml of synthetic sewage was added to the mixture. Each sample was filtered through filter paper and diluted twenty times prior to the spectrophotometric measurement at the absorption maximum within the visible range. The decrease of dyes concentration was expressed in terms of percent to the initial absorption. The experiment was carried out for 10 days. Oxygen uptake of sludge [Warburg Method]- 2.0 ml of sludge, 0.2 ml of 1000 ppm dye solution, and 0.2 ml of 20% potassium hydroxide were pipetted into the vessel, the side arm and central well, respectively. The sludge and the dye solution were mixed and the vessel was shaken at 25°C. The oxygen uptake was measured. The oxygen uptake by sludge alone was subtracted from those by dyes addition.

Determination of BOD – Dye solution (10, 20, and 40 ppm) were prepared with the seeded dilution water and kept at 20°C (Japanese Industrial Standards Committee, 1971). The dissolved oxygen contents were measured by a dissolved oxygen meter, because of the coloration of the solutions.As there is no regulation on the color of the effluent by the Water Pollution Control Law, discharge of coloring materials is regulated by only BOD or COD. The COD, BOD and absorbance at 245 and 545 nm (representing ultraviolet and the visible absorbance) of Phloxine B was studied. During 10 days of the aerobic experiment, the absorbance of dye solution was measured once day for 10 days. Food Red No. 104 was scarcely decreased. Free acids of Red No.104, was precipitated due to the slight acidity (pH 6-7) of the solution. Based on the results obtained from the studies, it can be concluded that Phloxine B is not readily biodegradable under aerobic conditions. Phloxine B was found to be non- biodegradable in the anaerobic test also performed.

 

On the basis of above results of various study for test chemical and for its read across substance, it can be concluded that the test substance

Dialuminium tris(2-(2,4,5,7-tetrabromo-6-oxido-3-oxoxanthen-9-yl)benzoate) is not expected to be readily biodegradable in nature.