3',6'-bis(diethylamino)spiro[isobenzofuran-1(3H),9'-[9H]xanthene]-3-one

Endpoint summary

Description of key information

Repeated dose toxicity: oral
Since no compound related adverse effects on rats are observed, the no observed adverse effect level (NOAEL) relating to repeated dose for the given test material 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one is estimated to be 742.11 mg/kg/day via oral route of administration.

Repeated dose toxicity: inhalation
A short-term toxicity study does not need to be conducted because exposure of humans via inhalation in production and/or use is not likely as based on the provided thorough and rigorous exposure assessment.

Repeated dose toxicity: dermal
The acute toxicity value for substance 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one (as provided in section 7.2.3) is >2000 mg/kg body weight. The substance was also found to be not irritating to skin. Also, given the use of the chemical as dye compound; repeated exposure by the dermal route is unlikely. Thus, it is expected that substance 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one shall not exhibit 28 day repeated dose toxicity by the dermal route. In addition, there is no dermal absorption data as well as no data available that suggests that substance 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one shall exhibit repeated dose toxicity by the dermal route. Hence this end point was considered for waiver.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: oral

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:

Data is predicted by OECD QSAR Toolbox version 3.3. The supporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

Data is predicted by OECD QSAR Toolbox version 3.3.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of the test material: 3',6'-bis(diethylamino)spiro[isobenzofuran-1(3H),9'-[9H]xanthene]-3-one
- Molecular formula: C28H30N2O3
- Molecular weight: 442.556 g/mol
- Substance type: Organic
- Smiles: C12(c3c(Oc4c1ccc(c4)N(CC)CC)cc(N(CC)CC)cc3)c1c(cccc1)C(O2)=O

Species:

rat

Strain:

not specified

Sex:

not specified

Route of administration:

oral: unspecified

Vehicle:

not specified

Analytical verification of doses or concentrations:

not specified

Frequency of treatment:

not specified

Remarks:

not specified

Control animals:

not specified

Details on study design:

not specified

Positive control:

not specified

Observations and examinations performed and frequency:

not specified

Sacrifice and pathology:

not specified

Other examinations:

not specified

Statistics:

not specified

Clinical signs:

effects observed, treatment-related

Mortality:

not specified

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

not specified

Food efficiency:

not specified

Water consumption and compound intake (if drinking water study):

not specified

Ophthalmological findings:

not specified

Haematological findings:

not specified

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Behaviour (functional findings):

not specified

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

not specified

Neuropathological findings:

not specified

Histopathological findings: non-neoplastic:

not specified

Histopathological findings: neoplastic:

not specified

Other effects:

not specified

Key result

Dose descriptor:

NOAEL

Effect level:

742.12 mg/kg bw/day (actual dose received)

Based on:

not specified

Sex:

not specified

Basis for effect level:

body weight and weight gain

clinical signs

Critical effects observed:

not specified

The prediction was based on dataset comprised from the following descriptors: NOAEL
Estimation method: Takes average value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

((((((("a" or "b" )  and ("c" and ( not "d") )  )  and ("e" and ( not "f") )  )  and "g" )  and "h" )  and "i" )  and ("j" and "k" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as SN1 AND SN1 >> Nitrenium Ion formation AND SN1 >> Nitrenium Ion formation >> Tertiary aromatic amine by DNA binding by OECD

Domain logical expression index: "b"

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: "c"

Referential boundary: The target chemical should be classified as No alert found by DNA binding by OASIS v.1.3

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as AN2 OR AN2 >> Michael-type addition on alpha, beta-unsaturated carbonyl compounds OR AN2 >> Michael-type addition on alpha, beta-unsaturated carbonyl compounds >> Four- and Five-Membered Lactones OR AN2 >> Shiff base formation after aldehyde release OR AN2 >> Shiff base formation after aldehyde release >> Specific Acetate Esters OR Non-covalent interaction OR Non-covalent interaction >> DNA intercalation OR Non-covalent interaction >> DNA intercalation >> DNA Intercalators with Carboxamide Side Chain OR Non-covalent interaction >> DNA intercalation >> Fused-Ring Primary Aromatic Amines OR Non-specific OR Non-specific >> Incorporation into DNA/RNA, due to structural analogy with  nucleoside bases    OR Non-specific >> Incorporation into DNA/RNA, due to structural analogy with  nucleoside bases    >> Specific Imine and Thione Derivatives OR Radical OR Radical >> Generation of ROS by glutathione depletion (indirect) OR Radical >> Generation of ROS by glutathione depletion (indirect) >> Haloalkanes Containing Heteroatom OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Fused-Ring Primary Aromatic Amines OR Radical >> Radical mechanism via ROS formation (indirect) >> Nitroarenes with Other Active Groups OR Radical >> Radical mechanism via ROS formation (indirect) >> Single-Ring Substituted Primary Aromatic Amines OR Radical >> Radical mechanism via ROS formation (indirect) >> Specific Imine and Thione Derivatives OR SN1 OR SN1 >> Alkylation after metabolically formed carbenium ion species OR SN1 >> Alkylation after metabolically formed carbenium ion species >> Polycyclic Aromatic Hydrocarbon Derivatives OR SN1 >> Nucleophilic attack after carbenium ion formation OR SN1 >> Nucleophilic attack after carbenium ion formation >> Specific Acetate Esters OR SN1 >> Nucleophilic attack after diazonium or carbenium ion formation OR SN1 >> Nucleophilic attack after diazonium or carbenium ion formation >> Nitroarenes with Other Active Groups OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> Fused-Ring Primary Aromatic Amines OR SN1 >> Nucleophilic attack after metabolic nitrenium ion formation >> Single-Ring Substituted Primary Aromatic Amines OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation OR SN1 >> Nucleophilic attack after reduction and nitrenium ion formation >> Nitroarenes with Other Active Groups OR SN1 >> Nucleophilic substitution on diazonium ions OR SN1 >> Nucleophilic substitution on diazonium ions >> Specific Imine and Thione Derivatives OR SN2 OR SN2 >> Acylation OR SN2 >> Acylation >> Specific Acetate Esters OR SN2 >> Alkylation, direct acting epoxides and related OR SN2 >> Alkylation, direct acting epoxides and related >> Epoxides and Aziridines OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation >> Polycyclic Aromatic Hydrocarbon Derivatives OR SN2 >> Alkylation, ring opening SN2 reaction OR SN2 >> Alkylation, ring opening SN2 reaction >> Four- and Five-Membered Lactones OR SN2 >> Direct acting epoxides formed after metabolic activation OR SN2 >> Direct acting epoxides formed after metabolic activation >> Quinoline Derivatives OR SN2 >> Nucleophilic substitution at sp3 Carbon atom OR SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Haloalkanes Containing Heteroatom OR SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Specific Acetate Esters OR SN2 >> SN2 at an activated carbon atom OR SN2 >> SN2 at an activated carbon atom >> Quinoline Derivatives OR SN2 >> SN2 attack on activated carbon Csp3 or Csp2 OR SN2 >> SN2 attack on activated carbon Csp3 or Csp2 >> Nitroarenes with Other Active Groups by DNA binding by OASIS v.1.3

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as SN1 AND SN1 >> Nitrenium Ion formation AND SN1 >> Nitrenium Ion formation >> Tertiary aromatic amine by DNA binding by OECD

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Michael addition OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Alkyl phenols OR Michael addition >> P450 Mediated Activation to Quinones and Quinone-type Chemicals >> Hydroquinones OR No alert found OR SN1 >> Iminium Ion Formation OR SN1 >> Iminium Ion Formation >> Aliphatic tertiary amines OR SN1 >> Nitrenium Ion formation >> Aromatic azo OR SN1 >> Nitrenium Ion formation >> Aromatic nitro OR SN1 >> Nitrenium Ion formation >> Unsaturated heterocyclic azo by DNA binding by OECD

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as No superfragment by Superfragments ONLY

Domain logical expression index: "h"

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

Domain logical expression index: "i"

Similarity boundary:Target: CCN(CC)c1ccc2c(c1)Oc1cc(N(CC)CC)ccc1C21c2ccccc2C(=O)O1
Threshold=30%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization

Domain logical expression index: "j"

Parametric boundary:The target chemical should have a value of log Kow which is >= 0.642

Domain logical expression index: "k"

Parametric boundary:The target chemical should have a value of log Kow which is <= 8.73

Conclusions:

Since no compound related adverse effects on rats are observed, the no observed adverse effect level (NOAEL) relating to repeated dose for the given test material 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one is estimated to be 742.11 mg/kg/day via oral route of administration.

Executive summary:

The repeated dose toxicity of 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one  to rats was estimated using QSAR Toolboox version 3.3. Since no compound related adverse effects on rats are observed, the no observed adverse effect level (NOAEL) relating to repeated dose for the given test material 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one  is estimated to be 742.11 mg/kg/day via oral route of administration.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

742.11 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

Data is of k2 reliability and predicted by QSAR toolbox.

Repeated dose toxicity: inhalation - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: inhalation

Data waiving:

exposure considerations

Justification for data waiving:

a short-term toxicity study does not need to be conducted because exposure of humans via inhalation in production and/or use is not likely as based on the provided thorough and rigorous exposure assessment

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: dermal

Data waiving:

other justification

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Repeated dose toxicity: oral
The predicted data for target substance 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one (CAS 509-34-2) and the experimental study for its read across substance disodium 3-oxo-3H-spiro[2-benzofuran-1,9'-xanthene]-3',6'-diolate (CAS 518-47-8)has been investigated for potential of toxicity following repeated exposure via oral route and is presented below as a weight of evidence approach for classification of the target substance:

The repeated toxicity of 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one  to rats was estimated using QSAR Toolboox version 3.3. Since no compound related adverse effects on rats are observed, the no observed adverse effect level (NOAEL) relating to repeated dose for the given test material 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one  is estimated to be 742.11 mg/kg/day via oral route of administration.

In a short term toxicity study, CD Sprague-Dawley female rats were treated with structurally similar substance D&C YELLOW NO. 8 (CAS No. 518-47-8) in the concentration of 0, 100, 500 and 1500 mg/kg body weight/ day by oral gavage (Fd Chem. Toxic, Vol. 24, No. 8, pp. 819 823, 1986). Six rats died during the dosing period at 1500 mg/kg bw/day and Orange discoloration of the urine was observed in all the treated rats as compared to control. Similarly, green discoloration of the amniotic fluid and green colored small intestines were observed at 1500 mg/kg bw/day and green discoloration of the amniotic fluid was observed at 100 and 500 mg/kg bw/day treated rats as compared to control. There were slight reductions in body-weight gains in the high-dose group, compared with controls, throughout the dosing period. Therefore, NOAEL was considered to be 500 mg/kg body weight /day when CD Sprague-Dawley female rats were treated repeatedly with D&C YELLOW No. 8 orally by gavage from day 6 to 19 of gestation.

Yet in another study for the same structurally similar substance and from same source (Fd Chem. Toxic, Vol. 24, No. 8, pp. 819 823, 1986), Dutch Belted female Rabbits were treated with D&C YELLOW NO. 8 (CAS No. 518 -47 -8) in the concentration of 0, 30, 100 and 250 mg/kg body weight/ day by oral gavage.One rabbits died each in 30 and 250 mg/kg bw/day including control. One rabbit was aborted on day 28 of gestation at 250 mg/kg bw/day as compared to control. Pneumonia was observed in three rabbit which were died. Orange discoloration of the urine was observed in all the treated rabbits between days 7 and 28 of gestation as compared to control. In addition, no effects were observed on body weight and body weight gain and gross pathology of treated rabbits as compared to control. There were no biologically meaningful or statistically significant differences in the mean numbers of corpora lutea, total implantations+ early or late resorptions, viable foetuses, foetal sex distribution or mean foetal body weight in any of the treated groups as compared to the control group. At 30 and 100 mg/kg bw/day, malformations were observed in two foetuses from two litters. However, these values fell within the ranges of historical control data. Therefore, NOAEL was considered to be 250 mg/kg body weight /day when Dutch Belted female Rabbits were treated repeatedly with D&C YELLOW NO. 8 orally by gavage from day 6 to 27 of gestation.

On the basis of evidence from above studies, it can be presumed that there is no potential of target substance to be harmful to rat/rabbit following repeated exposure. Also, the substance didn’t show any specific target organ toxicity. Hence, based on the above study summarized with oral routes and by applying weight of evidence approach it can be concluded that 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one is not classified as toxic on Repeated dose exposure via oral route.

Repeated dose toxicity: inhalation
A short-term toxicity study does not need to be conducted because exposure of humans via inhalation in production and/or use is not likely as based on the provided thorough and rigorous exposure assessment.

Repeated dose toxicity: dermal
The acute toxicity value for substance 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one (as provided in section 7.2.3) is >2000 mg/kg body weight. The substance was also found to be not irritating to skin. Also, given the use of the chemical as dye compound; repeated exposure by the dermal route is unlikely. Thus, it is expected that substance 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one shall not exhibit 28 day repeated dose toxicity by the dermal route. In addition, there is no dermal absorption data as well as no data available that suggests that substance 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one shall exhibit repeated dose toxicity by the dermal route. Hence this end point was considered for waiver.

Justification for classification or non-classification

Based on the above study summarized with oral routes and by applying weight of evidence approach it can be concluded that 3',6'-bis(diethylamino)-3H-spiro[2-benzofuran-1,9'-xanthen]-3-one is not classified as toxic on Repeated dose exposure via oral route.