Registration Dossier
Registration Dossier
Data platform availability banner - registered substances factsheets
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Diss Factsheets
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 200-822-1 | CAS number: 74-93-1
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Genetic toxicity: in vivo
Administrative data
- Endpoint:
- in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus
- Remarks:
- Type of genotoxicity: chromosome aberration
- Adequacy of study:
- other information
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: GLP guideline study
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 1 997
- Report date:
- 1997
Materials and methods
Test guideline
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
- GLP compliance:
- yes
- Type of assay:
- micronucleus assay
Test material
- Reference substance name:
- Methanethiol
- EC Number:
- 200-822-1
- EC Name:
- Methanethiol
- Cas Number:
- 74-93-1
- Molecular formula:
- CH4S
- IUPAC Name:
- methanethiol
Constituent 1
Test animals
- Species:
- mouse
- Strain:
- Swiss Webster
- Sex:
- male/female
Administration / exposure
- Route of administration:
- inhalation
- Duration of treatment / exposure:
- 6 hours
Doses / concentrations
- Remarks:
- Doses / Concentrations:
0, 114, 258 and 512 ppm
Basis:
Results and discussion
Test results
- Sex:
- male/female
- Genotoxicity:
- negative
- Toxicity:
- yes
- Vehicle controls validity:
- valid
- Negative controls validity:
- not applicable
- Positive controls validity:
- valid
Any other information on results incl. tables
DOSE RANGE FINDING EXPERIMENT
No significant differences as observed between terminal and
pre-exposure body weights of each of the treatment groups at
each of the sacrifice times.
Clinical signs observed included shallow breathing at the
fourth hour of exposure at 112 ppm, shallow breathing at the
third hour of exposure at 374 and 570 ppm with hypoactivity
at the mid and high dose levels in all mice when observed
after completion of exposure. Two male mice were found dead
near the end of the second hour and during the sixth hour of
exposure at 570 ppm. Any mouse showing clinical signs
appeared normal on Day 2. Surviving mice were sacrificed
approximately 72 hours after the inhalation exposure, and
cytotoxicity was determined based on the ratio of
RNA-positive erythrocytes (PCEs) to total red blood cells
(RBCs) in both peripheral blood and bone marrow smears. No
significant PCE suppression was observed in any of the
methyl mercaptan treatment groups when compared to the air
control group in either peripheral blood or bone marrow.
DEFINITIVE EXPERIMENT
Clinical observations in this experiment included shallow
breathing and hypoactivity at the fourth and fifth hours,
respectively, of exposure at 258 ppm in all mice. All mice
at 258 ppm appeared normal on Day 2 and on all subsequent
experiment days. Shallow breathing at the third and fourth
hours of exposure, and hypoactivity at the fifth hour of
exposure were observed at 512 ppm in all mice. One female
mouse was found dead after 2 hours of exposure at 512 ppm,
and two female and two male mice were found dead at 512 ppm
on Day 2. All surviving mice at 512 ppm appeared normal on
Day 2 and on all subsequent experiment days. Mice treated
with 114 ppm methyl mercaptan, air control, or urethane
appeared normal throughout the experiment.
The percentages of PCEs among RBCs in groups treated with
methyl mercaptan did not differ significantly from those of
the air control groups in any of the dose groups for either
sex.
In male mice (Table 1), none of the individual dose groups
had a statistically significant increase in MN frequency. Using
the Cochran-Armitage test for a trend in binomial
proportions, a statistically significant upward trend in
micronucleus (MN) frequency was observed in female mice
(Table 2) sacrificed at 24 hr after exposure to the methyl mercaptan.
However, the MN frequency in the control group was lower
than the laboratory historical value (0.21%) for females of
this strain of mice, and none of the individual dose groups
had a statistically significant increase in MN frequency.
Applicant's summary and conclusion
- Conclusions:
- Interpretation of results (migrated information): negative
- Executive summary:
A mouse micronucleus assay was conducted with methanethiol inhalation exposure to male and female Swiss Webster mice according to the OECD 474 Guideline. The mice (15/sex/group) were exposed (nose-only) to methanethiol via inhalation at 0, 114, 258 and 512 ppm for 6 hours. A positive control group of male mice was exposed to urethane concurrently with the treated groups. Five mice/sex were sacrificed at 24, 48 and 72 hours after the single exposure and bone marrow was evaluated for cytotoxicity and micronucleus formation. One female mouse was found dead after 2 hours of 512 ppm exposure and 4 mice (2 males and 2 females) in the 512 ppm were found dead on Day 2. At 24 hours, there was a statistically-significant upward trend in micronuclei in females, but comparison of individual doses to controls did not yield statistically-significant differences and the control group value was lower than the laboratory historical mean The mean average value for the historical controls was determined on 11 studies performed between 1990 and 1994 and using in total 120 male and 120 female mice. It was concluded that methanethiol did not induce chromosome mutations under the conditions of this study.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.