2,4,7,9-tetramethyldec-5-yne-4,7-diol

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

According to the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS) Part 3 Chapter 3.5 this substance is not causing concern to be mutgenetic/genetic toxic.

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: according to EC Directive 92/69/EEC and Regulation EC/440/2008 guideline methods under GLP conditions

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Metabolic activation system:

S-9 mix

Test concentrations with justification for top dose:

0, 10, 50, 100, 500, 1000, and 5000 ug/plate

Vehicle / solvent:

DMSO

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

Migrated to IUCLID6: Sodium azide, 2-Nitrofluorene, 2-Anthramine

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 1000 µg/plate and above

Vehicle controls validity:

valid

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 1000 µg/plate and above

Vehicle controls validity:

valid

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 1000 µg/plate and above

Vehicle controls validity:

valid

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 1000 µg/plate and above

Vehicle controls validity:

valid

Positive controls validity:

valid

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 1000 µg/plate and above

Vehicle controls validity:

valid

Positive controls validity:

valid

The 5000 ug/plate dose formulation appeared to be immiscible in the tubes and on the plates. Precipitate was also observed in the tubes and on the plates at a dose level of 5000 ug. However after the 48-hour incubation period the precipitate was no longer seen on the plates. Cytotoxicity, indicated by thinning of the background bacterial lawn and the formation of pinpoint nonrevertant colonies, was observed for all strains generally at dose levels of 1000 and 5000 ug/plate. 
No 2,4,7,9-tetramethyl-5-decyne-4,7-diol treatments of the test strains resulted in an increase in revertant numbers that was considered indicative of any mutagenic activity.

Conclusions:

No 2,4,7,9-tetramethyl-5-decyne-4,7-diol treatments of the test strains resulted in an increase in revertant numbers that was considered indicative of any mutagenic activity.

Executive summary:

2,4,7,9-Tetramethyl-5-decyne-4,7-diol was not mutagenic under the test conditions used in this bacterial assay. 2,4,7,9-tetramethyl-5-decyne-4,7-diol diluted in DMSO was examined for mutagenic activity in the Salmonella-Escherichia coli/microsome plate incorporation assay. The assay was performed using the standard plate incorporation procedure with S. typhimurium strains TA1535, TA1537, TA98, and TA100 and E. coli strain WP2 (uvrA) over a dose range of 10 to 5000 ug/plate in both the presence and absence of an Aroclor 1254-induced rat-liver metabolic activation system. The initial experiment used 5 percent (v/v) metabolic activation and the repeat experiment used 10 percent (v/v) metabolic activation. The 5000 ug/plate dose formulation appeared to be immiscible in the tubes and on the plates. Precipitate was also observed in the tubes and on the plates at a dose level of 5000 ug. However after the 48-hour incubation period the precipitate was no longer seen on the plates. Cytotoxicity, indicated by thinning of the background bacterial lawn and the formation of pinpoint nonrevertant colonies, was observed for all strains generally at dose levels of 1000 and 5000 ug/plate. No 2,4,7,9-tetramethyl-5-decyne-4,7-diol treatments of the test strains resulted in an increase in revertant numbers that was considered indicative of any mutagenic activity.

Reference 2

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: according to EC Directive 92/69/EEC and Regulation EC/440/2008 guideline methods under GLP conditions

Qualifier:

according to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

GLP compliance:

yes

Type of assay:

in vitro mammalian chromosome aberration test

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Test concentrations with justification for top dose:

19.5, 39.1, 78.1-78.3, 156.3, 312.5, 1250, and 3500 ug/ml

Vehicle / solvent:

DMSO

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: 312.5

Remarks on result:

other: other: CHO Cells

Remarks:

Migrated from field 'Test system'.

RS-Freetext:
In the cytotoxicity experiment, all of the cultures from the
top two dose levels exhibited a significant decrease in
confluency (0 to 25 percent) and therefore were not
harvested. For cultures exposed to the test article for 3 hr
in the presence or absence of MA, no significant reduction
in mitotic index was observed at dose levels of 312.5 ug/mL
and below. Cultures exposed for 21 hr to the test article at
312.5 ug/mL showed a significant reduction in mitotic index.
In the initial chromosome aberration experiment,
cytotoxicity was evident in cultures exposed to 312.5 ug/mL
under both MA conditions, so the cells were not harvested
for evaluation.

In both the initial chromosome aberration experiment and in
the replicate experiment, there was no statistically
significant increase in the number of cells with structural
aberrations at the three dose levels scored in both MA
conditions (39.1, 78.1, and 156.3 ug/mL).  The mitotic index
was comparable to that for the control and no increases in
polyploidy were observed in the presence or absence of MA.

Conclusions:

Interpretation of results (migrated information):
negative

This study was performed to evaluate the ability of 2,4,7,9-tetramethyl-5-decyne-4,7-diol to induce chromosome aberrations in Chinese hamster ovary (CHO) cells in the presence and absence of rat S-9 metabolic activation (MA).

In the cytotoxicity assay, CHO cells were exposed to 2,4,7,9-tetramethyl-5-decyne-4,7-diol at concentrations of 19.5, 78.3, 312.5, 1250, and 3500 ug/ul in both the absence and presence of MA. A high dose of 3500 ug/ul was used based on the limit of solubility of the test article in dimethylsulfoxide (DMSO). Cells were exposed to the test article in the absence of MA for 3 and 21 hr and in the presence of MA for 3 hr. At 21 hr after exposure initiation, cells were harvested and evaluated. All of the cultures from the top two dose levels exhibited a significant decrease in confluency (0 to 25 percent) and therefore were not harvested. For cultures exposed to the test article for 3 hr in the presence or absence of MA, no significant reduction in mitotic index was observed at dose levels of 312.5 ug/ul and below. Cultures exposed for 21 hr to the test article at 312.5 ug/ul showed a significant reduction in mitotic index.

Based on the cytotoxicity results, the initial chromosome aberration study was performed by exposing CHO cells for 3 hr to 2,4,7,9-tetramethyl-5-decyne-4,7-diol at concentrations of 19.5, 39.1, 78.1, 156.3, and 312.5 ug/ul in both the absence and presence of MA. At 21 hr after initiation of exposure, cells were harvested and evaluated. Cytotoxicity was evident in cultures exposed to 312.5 ug/ul under both MA conditions, so the cells were not harvested for evaluation. In cultures at the three dose levels scored in both MA conditions (39.1, 78.1, and 156.3 ug/ul), there was no statistically significant increase in the number of cells with structural aberrations and the mitotic index was comparable to that for the control. No increases in polyploidy were observed in the presence or absence of MA.

The dose levels for the replicate experiment were based on the results of the cytotoxicity experiment (-MA) and the initial experiment (+MA) which indicated cytotoxicity and a significant reduction in confluency at the 312.5 ug/ul dose level. The replicate experiment was performed by exposing CHO cells for 21 hr to the test article at concentrations of 9.8, 19.5, 39.1, 78.1, and 156.3 ug/ul in the absence of MA and for 3 hr at concentrations of 19.5, 39.1, 78.1, and 156.3 ug/ul in the presence of MA. At 21 hr after initiation of exposure, cells were harvested and evaluated. At the three dose levels scored in both MA conditions (39.1, 78.1, and 156.3 ug/ul), there was no statistically significant increase in the number of cells with structural aberrations and the mitotic index was comparable to that for the control. No increases in polyploidy were observed in the presence or absence of MA.

Executive summary:

This study was performed to evaluate the ability of 2,4,7,9-tetramethyl-5-decyne-4,7-diol to induce chromosome aberrations in Chinese hamster ovary (CHO) cells in the presence and absence of rat S-9 metabolic activation (MA). In the cytotoxicity assay, CHO cells were exposed to 2,4,7,9-tetramethyl-5-decyne-4,7-diol at concentrations of 19.5, 78.3, 312.5, 1250, and 3500 ug/ul in both the absence and presence of MA. A high dose of 3500 ug/ul was used based on the limit of solubility of the test article in dimethylsulfoxide (DMSO). Cells were exposed to the test article in the absence of MA for 3 and 21 hr and in the presence of MA for 3 hr. At 21 hr after exposure initiation, cells were harvested and evaluated. All of the cultures from the top two dose levels exhibited a significant decrease in confluency (0 to 25 percent) and therefore were not harvested. For cultures exposed to the test article for 3 hr in the presence or absence of MA, no significant reduction in mitotic index was observed at dose levels of 312.5 ug/ul and below. Cultures exposed for 21 hr to the test article at 312.5 ug/ul showed a significant reduction in mitotic index. Based on the cytotoxicity results, the initial chromosome aberration study was performed by exposing CHO cells for 3 hr to 2,4,7,9-tetramethyl-5-decyne-4,7-diol at concentrations of 19.5, 39.1, 78.1, 156.3, and 312.5 ug/ul in both the absence and presence of MA. At 21 hr after initiation of exposure, cells were harvested and evaluated. Cytotoxicity was evident in cultures exposed to 312.5 ug/ul under both MA conditions, so the cells were not harvested for evaluation. In cultures at the three dose levels scored in both MA conditions (39.1, 78.1, and 156.3 ug/ul), there was no statistically significant increase in the number of cells with structural aberrations and the mitotic index was comparable to that for the control. No increases in polyploidy were observed in the presence or absence of MA. The dose levels for the replicate experiment were based on the results of the cytotoxicity experiment (-MA) and the initial experiment (+MA) which indicated cytotoxicity and a significant reduction in confluency at the 312.5 ug/ul dose level. The replicate experiment was performed by exposing CHO cells for 21 hr to the test article at concentrations of 9.8, 19.5, 39.1, 78.1, and 156.3 ug/ul in the absence of MA and for 3 hr at concentrations of 19.5, 39.1, 78.1, and 156.3 ug/ul in the presence of MA. At 21 hr after initiation of exposure, cells were harvested and evaluated. At the three dose levels scored in both MA conditions (39.1, 78.1, and 156.3 ug/ul), there was no statistically significant increase in the number of cells with structural aberrations and the mitotic index was comparable to that for the control. No increases in polyploidy were observed in the presence or absence of MA.

Reference 3

Endpoint:

in vitro gene mutation study in mammalian cells

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: according to EC Directive 92/69/EEC and Regulation EC/440/2008 guideline methods under GLP conditions

Qualifier:

according to guideline

Guideline:

OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)

GLP compliance:

yes

Type of assay:

mammalian cell gene mutation assay

Species / strain / cell type:

mouse lymphoma L5178Y cells

Details on mammalian cell type (if applicable):

- Type and identity of media:
- Periodically "cleansed" against high spontaneous background: yes

Metabolic activation:

with and without

Metabolic activation system:

S9

Test concentrations with justification for top dose:

8.83 to 2260 µg/ml

Vehicle / solvent:

DMSO

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

ethylmethanesulphonate

Remarks:

Migrated to IUCLID6: ethylmethanesulphonate in in the absence of of metabolic activation; cyclophosphamide in the presence of metabolic activation

Species / strain:

mouse lymphoma L5178Y cells

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not determined

Vehicle controls validity:

valid

Positive controls validity:

valid

Additional information on results:

Two independent experiments wre performed. In Experiment 1, L5178Y TK +/- 3.7.2c mouse lymphoma cells (heterozyous at the thymidine kinase locus) were treated with the test material at up to eight dose levels, in duplicate, together with vehicle (solvent) and positive controls using 4 -hour exposure groups both in the asence and presence of metabolic activation (2% S9). In experiment 2, the cells were treated with the test material at up to eight dose levels using a 4 -hour exposure group in the absence of metabolic activation.
The dose range of test material was selected following the results of a preliminary toxicity test and for the first experiment was 4.38 to 140 µg/ml in the absence of metabolic activation, and 17.5 to 280 µg/ml in the presence of metabolic activation. For the second experiment the dose range was 4.38 to 140 µg/ml in the absence of metabolic activation, and 17.5 to 210 µg/ml in the presence of metabolic activation.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results (migrated information):
negative non-mutagenic

The test material was considered to be non-mutagenic to L5178Y cells under the conditions of the test.

Executive summary:

Introduction:

The study was conducted according to a method that was designed to assess the potential mutagenicity of the test material on the thymidine kinase, TK +/-, locus of the L5178Y mouse lymphoma cell line, >>The method used meets the requirements of the OECD (476) and the Method B17 of Commission Regulation (EC) No. 440/2008 of 30 May 2008.

Methods:

Two independent experiments wre performed. In Experiment 1, L5178Y TK +/- 3.7.2c mouse lymphoma cells (heterozyous at the thymidine kinase locus) were treated with the test material at up to eight dose levels, in duplicate, together with vehicle (solvent) and positive controls using 4 -hour exposure groups both in the asence and presence of metabolic activation (2% S9). In experiment 2, the cells were treated with the test material at up to eight dose levels using a 4 -hour exposure group in the absence of metabolic activation.

The dose range of test material was selected following the results of a preliminary toxicity test and for the first experiment was 4.38 to 140 µg/ml in the absence of metabolic activation, and 17.5 to 280 µg/ml in the presence of metabolic activation. For the second experiment the dose range was 4.38 to 140 µg/ml in the absence of metabolic activation, and 17.5 to 210 µg/ml in the presence of metabolic activation.

Results:

THe maximum dose level used in the mutagenicity test was limited by test material-induced toxicity. Precipitate of the test material was not observed at any of the dose levels in the mutagenicity test. The vehicle (solvent) controls had acceptable mutant frequency values that were within the normal range for the L5178Y cel line at the TK +/- locus. The positive control materials induced marked increases in the mutant frequency indicating the satisfactory perfomance of the test and of the activity of the metabolising system.

The test material did not induce any toxicologically significant dose-related increases in the mutant frequency at any dose level, either with or without metabolic activation, in either the first or the second experiment.

Conclusion:

The test material was considered to be non-mutagenic to L5178Y cells under the conditions of the test.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Mode of Action Analysis / Human Relevance Framework

There is no evidence for species specific effects of the substance. Therefore, the results of the in vitro data are regarded as relevant for humans. 

Additional information

Additional information from genetic toxicity in vitro:

The test material was considered to be non-mutagenic according to the test conditions as given in OCED guidelines 471, 473 and 476.

Justification for selection of genetic toxicity endpoint
This study contains data which meets the criteria set forth in Regulation EC No. 440/2008 for filling REACH endpoints. The data is generated in a reliable laboratory using established protocols. It is supported by studies following OECD TG 471 and 473.

Justification for classification or non-classification

According to the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS) Part 3 Chapter 3.5 this substance is not causing concern to be mutgenetic/genetic toxic.