Androsta-1,4-diene-3,17-dione

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Androstadiendion is negative with and without metabolic activation in a bacterial reverse mutation assay (Ames test) (Wollny, 1995). In addition, an Ames test (Reimann, 1996) and a HPRT assay in V79 cells (Wollny, 2013) revealed negeative results with the read-across substance androstendion.

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:

July 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

- only one experiment was performed

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Target gene:

Histidine gene locus

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254 induced male rat liver S9 mix

Test concentrations with justification for top dose:

33.3, 100, 333.3, 1000, 2500, 5000 µg/plate

Vehicle / solvent:

DMSO

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: without metabolic activation: Sodium azide, 4-Nitro-o-phenylenediamine, Methyl methane sulfonate; with metabolic activation: 2-Aminoanthracene

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

without metabolic activation: at 1000 µg/plate and above in strains TA 1535, TA 1537 and TA 102; with metabolic activation: at 5000 µg/plate in strain TA 1535 as well as at 1000 µg/plate and above in strains TA 1537 and TA 102

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Distinct toxic effects, evidenced by a reduction in the number of revertants and a reduced background growth at 5000 µg/plate, occurred in strains TA 1535, TA 1537 and TA 102 without metabolic activation from 1000 µg/plate up to 5000 µg/plate. With metabolic activation toxic effects occurred in strain TA 1535 at 5000 µg/plate and in strain TA 1537 and TA 102 from 1000 up to 5000 µg/plate.

 

No substantial increases in revertant colony numbers of any of the five tester strains were observed following treatment with ZK 4947 at any concentration level, either in the presence or absence of metabolic activation (S9 mix). There was also no tendency of higher mutation rates with increasing concentrations in the range below the generally acknowledged border of biological relevance.

 

Appropriate control mutagens were used as positive controls. They showed a distinct increase in induced revertant colonies.

Conclusions:

Interpretation of results (migrated information):
negative

Executive summary:

The mutagenic potential of the test substance was evaluated in a Salmonella/microsome test with the S. typhimurium strains TA 98, TA 100, TA 102, TA 1535 and TA 1537 in the presence and absence of S9 mix according to OECD TG 471. Evidence of mutagenic activity was not seen up to the maximum recommended dose level of 5000 µg/plate. No substantial increases in revertant colony numbers of any of the five tester strains were observed at any dose level in the presence and absence of metabolic activation. There was also no tendency of higher mutation rates with increasing concentrations in the range below the generally acknowledged border of biological relevance. Therefore, the test substance was considered to be non-mutagenic in the Salmonella typhimurium reverse mutation assay.

Reference 2

Endpoint:

in vitro gene mutation study in mammalian cells

Remarks:

Type of genotoxicity: gene mutation

Type of information:

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

Adequacy of study:

key study

Study period:

May to Aug 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

(1997)

GLP compliance:

yes (incl. QA statement)

Type of assay:

mammalian cell gene mutation assay

Target gene:

HPRT locus

Species / strain / cell type:

Chinese hamster lung fibroblasts (V79)

Details on mammalian cell type (if applicable):

- Type and identity of media: MEM with supplements; for the selection of mutant cells the medium was supplemented with 11 µg/mL 6-thioguanine.
- Properly maintained: yes
- Periodically "cleansed" against high spontaneous background: yes
- Periodically checked for karyotype stability: yes
- Periodically checked for Mycoplasma contamination: yes

Metabolic activation:

with and without

Metabolic activation system:

S9-Mix from the liver of phenobarbital/ß-naphthoflavone induced rats.

Test concentrations with justification for top dose:

Experiment I: treatment time 4 hours, with and without S9 mix 7.5, 15.0, 30.0, 60.0, 120.0, and 240.0 µg/mL
Experiment II: treatment time 4 hours, with S9 mix 7.5, 15.0, 30.0, 60.0, 120.0, 180.0, and 240.0 µg/mL; treatment time 24 hours, without S9 mix 1.89, 3.75, 7.5, 15.0, 30.0, 60.0, 90.0, and 120.0 µg/mL.

Vehicle / solvent:

DMSO
- Justification for choice of solvent/vehicle: The solvent was chosen due to its solubility properties and its relative non-toxicity to the cell cultures.

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: ethylmethanesulfonate (EMS; 1.2 mM), 7,12-dimethylbenzanthracene (DMBA; 4.3 µM)

Remarks:

EMS was used without and DMBA with metabolic activation

Details on test system and experimental conditions:

PRE-TEST: Test item concentrations ranged between 15.0 ¿g/mL and 1920 ¿g/mL in the pre-experiment. As result no relevant toxic effect occurred up to the maximum concentration tested with and without metabolic activation following 4 hour treatment. A transient reduction of the cloning efficiency to 44.1 % at 480 ¿g/mL without metabolic activation was judged as precipitation artefact rather than true cytotoxicity as the cloning efficiency was back to normal at higher concentrations. Following 24 hours treatment without metabolic activation cytotoxic effects occurred at 120 ¿g/mL and above.

METHOD OF APPLICATION: in medium
Approximately 1.5×10exp6 (single culture) and 5×102 cells (in duplicate) were seeded in plastic culture flasks. The cells were grown for 24 hours prior to treatment. After 24 hours the medium was replaced with serum-free medium containing the test item, either without S9 mix or with 50 ¿l/mL S9 mix. Concurrent solvent and positive controls were treated in parallel. After 4 hours this medium was replaced with complete medium following two washing steps with "saline G". In the second experiment the cells were exposed to the test item for 24 hours in complete medium, supplemented with 10 % FBS, in the absence of metabolic activation.
Three or four days after treatment 1.5×10exp6 cells per experimental point were sub-cultivated in 175 cm² flasks containing 30 mL medium. Following the expression time of 7 days five 80 cm² cell culture flasks were seeded with about 3 - 5×10exp5 cells each in medium containing 6-TG. Two additional 25 cm² flasks were seeded with approx. 500 cells each in non-selective medium to determine the viability.
The cultures were incubated at 37 °C in a humidified atmosphere with 1.5 % CO2 for about 8 days. The colonies were stained with 10 % methylene blue in 0.01 % KOH solution.
The stained colonies with more than 50 cells were counted. In doubt the colony size was checked with a preparation microscope.

DURATION
- Exposure duration: 4 hours
- Expression time (cells in growth medium): 7 days
- Selection time: 8 days

DETERMINATION OF CYTOTOXICITY
- Method: cloning efficiency

Evaluation criteria:

A test item is classified as positive if it induces either a concentration-related increase of the mutant frequency or a reproducible and positive response at one of the test points. A test item producing neither a concentration-related increase of the mutant frequency nor a reproducible positive response at any of the test points is considered non-mutagenic in this system.
A positive response is described as follows: A test item is classified as mutagenic if it reproducibly induces a mutation frequency that is three times above the spontaneous mutation frequency at least at one of the concentrations in the experiment. The test item is classified as mutagenic if there is a reproducible concentration-related increase of the mutation frequency. Such evaluation may be considered also in the case that a threefold increase of the mutant frequency is not observed. However, in a case by case evaluation this decision depends on the level of the corresponding solvent control data. If there is by chance a low spontaneous mutation rate within the laboratory¿s historical control data range, a concentration-related increase of the mutations within this range has to be discussed. The variability of the mutation rates of solvent controls within all experiments of this study was also taken into consideration.

Statistics:

A linear regression (least squares) was performed to assess a possible dose dependent increase of mutant frequencies.

Key result

Species / strain:

Chinese hamster lung fibroblasts (V79)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

No substantial and reproducible dose dependent increase of the mutation frequency was observed in both main experiments. Appropriate reference mutagens, used as positive controls, induced a distinct increase in mutant colonies and thus, showed the sensitivity of the test system and the activity of the metabolic activation system.

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH and osmolarity: There was no relevant shift of pH and osmolarity of the medium even at the maximum concentration of the test item.
- Water solubility: The maximum concentration of the pre-experiments (1920 ¿g/mL) was based on the solubility properties of the test item in DMSO and aqueous medium.
- Precipitation: No precipitation of the test item was observed up to the maximum analyzable concentration in both main experiments. In the pre-experiments precipitation occurred at 120 ¿g/mL and above after 4 hours treatment with and without metabolic activation, and at 480 ¿g/mL and above following 24 hours treatment without metabolic activation.

ADDITIONAL INFORMATION ON CYTOTOXICITY:
Cytotoxic effects indicated by a relative cloning efficiency I or relative cell density below 50 % of the corresponding solvent control were noted at 120 ¿g/mL in the first main experiment without metabolic activation. In the presence of metabolic activation no cytotoxicity was observed at the maximum analyzable concentration of 120 ¿g/mL. At the next higher concentration of 240 ¿g/mL exceedingly severe cytotoxic effects precluded analysis of any data on mutagenicity. In the second experiment cytotoxicity as described above occurred at 180 ¿g/mL with and at 120 ¿g/mL without metabolic activation. The recommended cytotoxic range of approximately 10-20 % relative cloning efficiency I or relative cell density was covered with and without metabolic activation.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Conclusions:

negative

Executive summary:

The test item did not induce substantial and reproducible dose dependent increase of the mutation frequency in a mammalian cell gene mutation assay (HPRT) according to OECD TG 476. In this assay two independent experiments were conducted with V79 cells being treated for either 4 hours with and without metabolic activation or 24 hours without metabolic activation. Appropriate reference mutagens, used as positive controls, induced a distinct increase in mutant colonies and thus, showed the sensitivity of the test system and the activity of the metabolic activation system. Therefore, the substance was considered to be non-mutagenic in the specified test.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Description of key information

A micronucleus test in male rats revealed negative results with the read-across substance androstendion (NTP, 2010). A second micronucleus testin mice, in which androstenedion was administered by gavage for 3 months, were negative in males but judged to be equivocal in females due to a small increase (two-fold over background) in micronucleated normochromatic erythrocytes observed at the highest dose administered (50 mg/kg) (NTP, 2010).

Link to relevant study records

Reference

Reference 1

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

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

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study (supervised by NTP); published data without detailed documentation

Qualifier:

according to guideline

Guideline:

other: NTP laboratory health and safety guidelines

Qualifier:

according to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Principles of method if other than guideline:

The study was performed according to standard three-exposure protocol as described by Shelby et al., Environ. Mol. Mutagen. 21, 1993, 160-179.

Cited from report: "These are the basic guidelines for arriving at an overall assay result for assays performed by the National Toxicology Program. Statistical as well as biological factors are considered. For an individual assay, the statistical procedures for data analysis have been described in the preceding protocols. There have been instances, however, in which multiple aliquots of a chemical were tested in the same assay, and different results were obtained among aliquots and/or among laboratories. Results from more than one aliquot or from more than one laboratory are not simply combined into an overall result. Rather, all the data are critically evaluated, particularly with regard to pertinent protocol variations, in determining the weight of evidence for an overall conclusion of chemical activity in an assay. In addition to multiple aliquots, the in vitro assays have another variable that must be considered in arriving at an overall test result. In vitro assays are conducted with and without exogenous metabolic activation. Results obtained in the absence of activation are not combined with results obtained in the presence of activation; each testing condition is evaluated separately." The summary table in the Abstract of the Technical Report presents a result that represents a scientific judgement of the overall evidence for activity of the chemical in an assay.

GLP compliance:

not specified

Type of assay:

micronucleus assay

Species:

rat

Strain:

Fischer 344

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Strain: F344/N
no further data in NTP TR 560

Route of administration:

oral: gavage

Vehicle:

- Vehicle(s)/solvent(s) used: corn oil

Details on exposure:

Preliminary range-finding studies were performed. Factors affecting dose selection included chemical solubility and toxicity and the extent of cell cycle delay induced by androstenedione exposure.

Duration of treatment / exposure:

3 days; The animals were killed 24 hours after the third dosing and bone marrow samples prepared.

Frequency of treatment:

three times at 24-hour interval

Post exposure period:

24 hours

Remarks:

Doses / Concentrations:
312.5 and 625 mg/kg bw
Basis:
actual ingested
exposure: 3 days

No. of animals per sex per dose:

5

Control animals:

yes, concurrent vehicle

Positive control(s):

The positive control animals received injections of cyclophosphamide (15 or 25 mg/kg).

Tissues and cell types examined:

The animals were killed 24 hours after the third dosing, and blood smears were prepared from bone marrow cells obtained from the femurs. Air-dried smears were fixed and stained. 2000 polychromatic erythrocytes (PCEs; reticulocytes) were scored for the frequency of micronucleated cells in each of up to five animals per dose group. In addition, the percentage of PCEs among the total erythrocyte population in the bone marrow was scored for each dose group as a measure of toxicity.

Evaluation criteria:

In the micronucleus test, an individual trial is considered positive if the trend test P value is less than or equal to 0.025 or if the P value for any single dosed group is less than or equal to 0.025 divided by the number of dosed groups. A final call of positive for micronucleus induction is preferably based on reproducibly positive trials. Ultimately, the final call is determined by the scientific staff after considering the results of statistical analyses, the reproducibility of any effects observed, and the magnitudes of those effects.

Statistics:

The frequency of micronucleated cells among PCEs was analyzed by a statistical software package that tested for increasing trend over dose groups with a one-tailed Cochran-Armitage trend test, followed by pairwise comparisons between each dosed group and the control group (Integrated Laboratory Systems (ILS), Micronucleus Data Management and Statistical Analysis Software, Version 1.4. ILS, Inc., P.O. Box 13501, Research Triangle Park, NC 277071990, 1990). In the presence of excess binomial variation, as detected by a binomial dispersion test, the binomial variance of the Cochran-Armitage test was adjusted upward in proportion to the excess variation.

Key result

Sex:

male

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

In vivo, no significant increases in the frequencies of micronucleated PCEs (reticulocytes) were observed in bone marrow of male F344/N rats administered androstenedione (312.5 or 625 mg/kg) by gavage once daily for 3 days. No significant changes in the percentages of PCEs among total erythrocytes were seen in the rats, suggesting no androstenedione-associated toxicity in the bone marrow.

Conclusions:

negative

Executive summary:

Cited from NTP-report:

"No significant increases in the frequencies of micronucleated polychromatic erythrocytes, indicators of chromosomal damage, were observed in bone marrow of male rats administered androstenedione by gavage once daily for 3 consecutive days."

Reference 2

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

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

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study (supervised by NTP); published data without detailed documentation

Qualifier:

according to guideline

Guideline:

other: NTP laboratory health and safety guidelines

Principles of method if other than guideline:

A detailed discussion of this assay is presented by MacGregor et al., Fundam. Appl. Toxicol. 14, 1990, 513-522.

Cited from report: "These are the basic guidelines for arriving at an overall assay result for assays performed by the National Toxicology Program. Statistical as well as biological factors are considered. For an individual assay, the statistical procedures for data analysis have been described in the preceding protocols. There have been instances, however, in which multiple aliquots of a chemical were tested in the same assay, and different results were obtained among aliquots and/or among laboratories. Results from more than one aliquot or from more than one laboratory are not simply combined into an overall result. Rather, all the data are critically evaluated, particularly with regard to pertinent protocol variations, in determining the weight of evidence for an overall conclusion of chemical activity in an assay. In addition to multiple aliquots, the in vitro assays have another variable that must be considered in arriving at an overall test result. In vitro assays are conducted with and without exogenous metabolic activation. Results obtained in the absence of activation are not combined with results obtained in the presence of activation; each testing condition is evaluated separately." The summary table in the Abstract of the Technical Report presents a result that represents a scientific judgement of the overall evidence for activity of the chemical in an assay.

GLP compliance:

not specified

Type of assay:

micronucleus assay

Species:

mouse

Strain:

not specified

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
no further data in NTP TR 560

Route of administration:

oral: gavage

Vehicle:

methylcellulose

Duration of treatment / exposure:

3 months

Frequency of treatment:

once daily

Post exposure period:

24 hours

Remarks:

Doses / Concentrations:
1 to 50 mg/kg bw
Basis:
actual ingested
exposure: 3 month

No. of animals per sex per dose:

5

Control animals:

yes, concurrent vehicle

Positive control(s):

none

Tissues and cell types examined:

At the end of the 3-month toxicity study (see chapter repeated dose toxicity for further results), peripheral blood samples were obtained from male and female mice. Smears were immediately prepared and fixed in absolute methanol. The methanol-fixed slides were stained with acridine orange and coded. Slides were scanned to determine the frequency of micronuclei in 2000 normochromatic erythrocytes (NCEs) in each of five animals per dose group. In addition, the percentage of PCEs among the total erythrocyte population was determined as a measure of bone marrow toxicity.

Evaluation criteria:

In the micronucleus test, an individual trial is considered positive if the trend test P value is less than or equal to 0.025 or if the P value for any single dosed group is less than or equal to 0.025 divided by the number of dosed groups. A final call of positive for micronucleus induction is preferably based on reproducibly positive trials. Ultimately, the final call is determined by the scientific staff after considering the results of statistical analyses, the reproducibility of any effects observed, and the magnitudes of those effects.

Statistics:

The results were tabulated as the mean of the pooled results from all animals within a treatment group plus or minus the standard error of the mean. The frequency of micronucleated cells among NCEs was analyzed by a statistical software package that tested for increasing trend over dose groups with a one-tailed Cochran-Armitage trend test, followed by pairwise comparisons between each dosed group and the control group (Integrated Laboratory Systems (ILS), Micronucleus Data Management and Statistical Analysis Software, Version 1.4. ILS, Inc., P.O. Box 13501, Research Triangle Park, NC 277071990, 1990). In the presence of excess binomial variation, as detected by a binomial dispersion test, the binomial variance of the Cochran-Armitage test was adjusted upward in proportion to the excess variation.

Key result

Sex:

male

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

not applicable

Key result

Sex:

female

Genotoxicity:

ambiguous

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

not applicable

Additional information on results:

Following 3 months of androstenedione administration (1 to 50 mg/kg) by gavage, no increase in the frequency of micronucleated NCEs was seen in peripheral blood samples from male B6C3F1 mice. In female mice, a small increase in the frequency of micronucleated NCEs was observed at the highest dose tested (50 mg/kg); although not significantly elevated above the vehicle control (P=0.0142), this increase resulted in a significant trend (P=0.001), and the test in female mice was judged to be equivocal.
No significant changes in the percentages of PCEs among total erythrocytes were seen in mice, suggesting no androstenedione-associated toxicity in the bone marrow.

Conclusions:

equivocal

Executive summary:

Cited from NTP report:

"Results of a peripheral blood erythrocyte micronucleus test in mice, in which androstenedione was administered by gavage for 3 months, were negative in males but judged to be equivocal in females due to a small increase (twofold over background) in micronucleated normochromatic

erythrocytes observed at the highest dose administered (50 mg/kg)."

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

The mutagenic potential of androstadiendion was evaluated in a Salmonella/microsome test with the S. typhimurium strains TA 98, TA 100, TA 102, TA 1535 and TA 1537 in the presence and absence of S9 mix according to OECD TG 471 (Wollny, 1995). Evidence of mutagenic activity was not seen up to the maximum recommended dose level of 5000 µg/plate. No substantial increases in revertant colony numbers of any of the five tester strains were observed at any dose level in the presence and absence of metabolic activation. There was also no tendency of higher mutation rates with increasing concentrations in the range below the generally acknowledged border of biological relevance. Therefore, the test substance was considered to be non-mutagenic in the Salmonella typhimurium reverse mutation assay. The structural analogue substance androstendion did also not show a mutagenic potential in an Ames test with the S. typhimurim strains TA 98, TA 100, TA 102, TA 1535 and TA 1537 (Reimann, 1996) when tested up to the highest recommended dose level of 5000 µg/plate in the absence or presence of metabolic activation (OECD TG 471).

For androstadiendion (CAS No. 897-06-3) no HPRT or MNT in vivo data are available. Therefore, HPRT and MNT in vivo data of androstendion (CAS No.63-05 -8) were used. A search for structure-analogue substances using the QSAR Toolbox 3.3.5 recommended androstendion as one out of 11 category substances for a read-across approach (for details see QSAR OECD Toolbox Report on Androstadiendion attached in chapter 7, Endpoint Summary: Toxicological information).

Androstendion did not induce a substantial or reproducible dose dependent increase of the mutation frequency in a mammalian cell gene mutation assay (HPRT) according to OECD TG 476 (Wollny, 2013). In this assay two independent experiments were conducted with V79 cells being treated for either 4 hours with and without metabolic activation or 24 hours without metabolic activation. The substance was considered to be non-mutagenic in the specified test.

In addition, no significant increases in the frequencies of micronucleated polychromatic erythrocytes - indicators of chromosomal damage - were observed in bone marrow of male rats administered androstenedion by gavage once daily for 3 consecutive days (NTP, 2010). Results of a peripheral blood erythrocyte micronucleus test in mice, in which androstenedion was administered by gavage for 3 months, were negative in males but judged to be equivocal in females due to a small increase (two-fold over background) in micronucleated normochromatic erythrocytes observed at the highest dose administered (50 mg/kg) (NTP, 2010).

In summary, both androstendion and androstadiendion are considered to be non-genotoxic based on in vitro (Ames, HPRT) and in vivo (MNT) genotoxicity studies.

Justification for classification or non-classification

Based on the study results with androstadiendion and the read-across substance androstendion a classification according to Regulation (EC) No. 1272/2008 (CLP) is not required.