Ethoxybis(pentane-2,4-dionato-O,O')(propan-2-olato)titanium

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Read across valid as the substance tested is also titanate complex with acetylacetone, degrading in water to form simple alcohols and acetylacetone.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.5100 - Bacterial Reverse Mutation Test (August 1998)

Principles of method if other than guideline:

No deviation from guideline.

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Target gene:

Gene of histidine in Salmonella typhimurium and gene of tryptophan in Escherichia coli.

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Additional strain / cell type characteristics:

other: all with rfa- and deletion of uvr B gene. In strain TA98 and TA100, presence of R factor plasmid pKM101 enhances chemical and UV-induced mutagenesis via an increase in the error-prone repair pathway.

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

rat-liver homogenate activation system (S9)

Test concentrations with justification for top dose:

Eight concentrations of the test item (1.5, 5, 15, 50, 150, 500, 1500 and 5000 µg/plate) were assayed in triplicate against each tester strain, using the direct plate incorporation method.

The maximum concentration used for testing was 5000 µg/plate as the toxicity in Experiment 1 was not severe enough to preclude testing up to
the maximum recommended dose level.

Vehicle / solvent:

Vehicle(s)/solvent(s) used: Acetone
Supplier: Fisher Scientific
Batch number (purity) 1719831 (>99%) Exp Jul 2022

Justification for choice of solvent/vehicle: the test substance was immiscible in sterile distilled water and dimethyl sulphoxide but was fully miscible in acetone at 100 mg/mL.

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

9-aminoacridine

N-ethyl-N-nitro-N-nitrosoguanidine

benzo(a)pyrene

other: 2-Aminoanthracene (2AA)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium; in agar (plate incorporation); preincubation;

DURATION
- Preincubation period: 37 +/-3°C for 20 minutes with shaking
- Exposure duration: 37 +/-3°C for 48 hours.

NUMBER OF REPLICATIONS: 3

Evaluation criteria:

There are several criteria for determining a positive result. Any, one, or all of the following can be used to determine the overall result of the study:
1. A dose-related increase in mutant frequency over the dose range tested (De Serres and Shelby, 1979).
2. A reproducible increase at one or more concentrations.
3. Biological relevance against in-house historical control ranges.
4. Statistical analysis of data as determined by UKEMS (Mahon et al., 1989).
5. Fold increase greater than two times the concurrent solvent control for any tester strain (especially if accompanied by an out-of-historical range response (Cariello and Piegorsch, 1996)).

A test item will be considered non-mutagenic (negative) in the test system if the above
criteria are not met.

Statistics:

Statistical significance was confirmed by using Dunnetts Regression Analysis (* = p < 0.05) for those values that indicate statistically significant increases in the frequency of revertant colonies compared to the concurrent solvent control. Values that the program concluded as statistically significant but were within the in-house historical profile were not reported.

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Conclusions:

The target substance does not have mutagenic effect based on studies read-across from structural analogue.

Reference 2

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017 Jul 31 to 2017 Sep 22

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.5100 - Bacterial Reverse Mutation Test (August 1998)

Principles of method if other than guideline:

No deviation from guideline.

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Supplier: Borica Co., Ltd.
- Lot number: 200520P
- Expiration date of the lot/batch: 2018-Feb-20
- CAS number: 94233-27-9

Target gene:

Gene of histidine in Salmonella typhimurium and gene of tryptophan in Escherichia coli.

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Additional strain / cell type characteristics:

other: all with rfa- and deletion of uvr B gene. In strain TA98 and TA100, presence of R factor plasmid pKM101 enhances chemical and UV-induced mutagenesis via an increase in the error-prone repair pathway.

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

rat-liver homogenate activation system (S9)

Test concentrations with justification for top dose:

Eight concentrations of the test item (1.5, 5, 15, 50, 150, 500, 1500 and 5000 µg/plate) were assayed in triplicate against each tester strain, using the direct plate incorporation method.

The maximum concentration used for testing was 5000 µg/plate as the toxicity in Experiment 1 was not severe enough to preclude testing up to
the maximum recommended dose level.

Vehicle / solvent:

Vehicle(s)/solvent(s) used: Acetone
Supplier: Fisher Scientific
Batch number (purity) 1719831 (>99%) Exp Jul 2022

Justification for choice of solvent/vehicle: the test substance was immiscible in sterile distilled water and dimethyl sulphoxide but was fully miscible in acetone at 100 mg/mL.

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

9-aminoacridine

N-ethyl-N-nitro-N-nitrosoguanidine

benzo(a)pyrene

other: 2-Aminoanthracene (2AA)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium; in agar (plate incorporation); preincubation;

DURATION
- Preincubation period: 37 +/-3°C for 20 minutes with shaking
- Exposure duration: 37 +/-3°C for 48 hours.

NUMBER OF REPLICATIONS: 3

Evaluation criteria:

There are several criteria for determining a positive result. Any, one, or all of the following can be used to determine the overall result of the study:
1. A dose-related increase in mutant frequency over the dose range tested (De Serres and Shelby, 1979).
2. A reproducible increase at one or more concentrations.
3. Biological relevance against in-house historical control ranges.
4. Statistical analysis of data as determined by UKEMS (Mahon et al., 1989).
5. Fold increase greater than two times the concurrent solvent control for any tester strain (especially if accompanied by an out-of-historical range response (Cariello and Piegorsch, 1996)).

A test item will be considered non-mutagenic (negative) in the test system if the above
criteria are not met.

Statistics:

Statistical significance was confirmed by using Dunnetts Regression Analysis (* = p < 0.05) for those values that indicate statistically significant increases in the frequency of revertant colonies compared to the concurrent solvent control. Values that the program concluded as statistically significant but were within the in-house historical profile were not reported.

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Conclusions:

The test substance was considered to be non-mutagenic under the conditions of this test.

Executive summary:

The test substance was tested according to OECD guideline 471 "Bacterial Reverse Mutation Test".Salmonella typhimuriumstrains TA1535, TA1537, TA98 and TA100 andEscherichia colistrain WP2uvrAwere treated with the test item using both the Ames plate incorporation and pre-incubation methods at up to eight dose levels (1.5, 5, 15, 50, 150, 500, 1500 and 5000 µg/plate), in triplicate, both with and without the addition of a rat liver homogenate metabolizing system (10% liver S9 in standard co-factors).

The test substance was not mutagenic either with or without metabolic activation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

AMES test on the target substance showed no mutagenic effect either with or without metabolic activation.

As the target substance hydrolyses rapidly (half-life < 30 minutes) the intrinsic properties are related to hydrolysis products of the target substance. The hydrolysis products include ethanol, 2-propanol, acetylacetone and non-hazardous titanium dioxide. This information is used as a supporting evidence on the toxicity of the target substance in CSA.

 

Pentane-2,4-dione  

In vitro: No mutagenic effects were seen in the Ames test (except slightly mutagenic effect in theSalmonella typhimuriumstrain TA104) and in the HPRT -assay. A positive clastogenic effect in CHO cells was observed in the absence of metabolic activation.

in vivo:Allin vivogenotoxicity studies conducted in rats and mice by inhalation did neither increase the number of structural or numerical aberrations nor the number of micronuclei. In contrast 2,4-pentanedione was shown to produce statistically significant increases in the incidence of micronucleated PCEs in mice but not in rats after i.p. administration. Concerning effects on germ cells a dominant lethal assay showed slight effects on fertility parameters in the (untreated) pregnant females mated with substance treated males being exposed via the inhalation pathway, which are regarded as a consequence of an unusual low control value. In an in vivo mouse spermatogonia assay 2,4-pentanedione did not produce chromosomal aberrations after oral administration to male mice at a dose close to the MTD. Overall 2,4-pentanedione shows a direct clastogenic potential in vitro which is not expressed in vivo by the inhalational route. (UNEP SIDS, Pentane-2,4-dione)

 

Based on these findings, the target substance was considered no mutagenic potential.

Justification for classification or non-classification

Based on AMES study on the target substance and the weight of evidence approach of in vitro/vivo studies on the hydrolysis products, there is no need for classification of the substance for mutagenic effects in accordance with the criteria of CLP Regulation