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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 202-594-9 | CAS number: 97-61-0
- 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
Developmental toxicity / teratogenicity
Administrative data
- Endpoint:
- developmental toxicity
- Type of information:
- experimental study
- Adequacy of study:
- other information
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: see 'Remark'
- Remarks:
- Screening test method. Restrictions: compared to OECD 414 low number of dams and reduced scope of examination of malformations (number of fetuses and number of tissues reduced). Acceptable for assessment because a total of 15 structurally related acids were tested.
Data source
Referenceopen allclose all
- Reference Type:
- publication
- Title:
- Unnamed
- Year:
- 1 994
- Report date:
- 1994
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 1 991
- Report date:
- 1991
Materials and methods
- Principles of method if other than guideline:
- Method: other: Screening acc. to Chernoff, N. and Kavlock, J. Toxicol. Environ. Health, 10, 541-550, 1982
- GLP compliance:
- not specified
- Limit test:
- no
Test material
- Reference substance name:
- 2-methylvaleric acid
- EC Number:
- 202-594-9
- EC Name:
- 2-methylvaleric acid
- Cas Number:
- 97-61-0
- Molecular formula:
- C6H12O2
- IUPAC Name:
- 2-methylpentanoic acid
- Details on test material:
- - Source: Chem. Dynamics Corp., not further specified
Constituent 1
Test animals
- Species:
- rat
- Strain:
- Sprague-Dawley
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: Charles River Laboratories, Raleigh, NC, USA
- Time mated
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22.2 +/- 1°C
- Humidity (%): 50 +/- 10%
- Photoperiod (hrs dark / hrs light): 12/12
Administration / exposure
- Route of administration:
- oral: gavage
- Vehicle:
- corn oil
- Details on exposure:
- VEHICLE
- Justification for use and choice of vehicle (if other than water): low water solubility
- Concentration in vehicle: 375 and 500 mg/mL
- Amount of vehicle (if gavage): 1 mL/kg bw - Analytical verification of doses or concentrations:
- not specified
- Details on mating procedure:
- Time-mated animals
- Duration of treatment / exposure:
- Gestation days 6 - 15
- Frequency of treatment:
- once per day
- Duration of test:
- Duration of test: up to post-natal day 6
Doses / concentrations
- Remarks:
- Doses / Concentrations:
0, 187.5 and 250 mg/kg bw and day
Basis:
actual ingested
- No. of animals per sex per dose:
- Controls: 20
Treated: 15 - Control animals:
- yes, concurrent vehicle
- Details on study design:
- Sex: female
- Dose selection rationale: based on the results on maternal toxicity of pilot studies using non-gravid rats. The high dose was expected to produce moderate maternal toxicity and the low dose was 75% of the high dose.
Examinations
- Maternal examinations:
- CAGE SIDE OBSERVATIONS: Yes
- Time schedule: at least daily
- Results: report, table 1
DETAILED CLINICAL OBSERVATIONS: No data
BODY WEIGHT: Yes
- Time schedule for examinations: GD 6, 8, 10, 13, 16, and 20
POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day 6
- Organs examined: uterine implantation sites - Ovaries and uterine content:
- The ovaries and uterine content was examined after termination: Yes / No / No data
Examinations included:
- Gravid uterus weight: No data
- Number of corpora lutea: No data
- Number of implantations: Yes - Fetal examinations:
- - External examinations: Yes: all per litter
- Soft tissue examinations: Yes: half per litter
- Skeletal examinations: Yes: 2 per litter; one per sex if possible
- Head examinations: No - Statistics:
- Dams that died or had only one implant were excluded from statistics. General linear model was used. Visceral alterations in fetuses were only examined in dead pups and were therefore excluded from statistics. When a significant treatment effect was detected by analysis of variance, Student’s t-test was used to identify significantly different groups.
- Indices:
- not calculated
- Historical control data:
- Indenpendent controls (n=20) were run for each of the 15 test substances, i.e. a total of 300 control animals was analysed
Results and discussion
Results: maternal animals
Maternal developmental toxicity
- Details on maternal toxic effects:
- Maternal toxic effects:yes
Details on maternal toxic effects:
% animals affected:
Controls: rales (5). Body weight change (g) GD 6-20: 58.4; n=18
375 mg/kg bw /d: rales (100); dyspnea (40), motor depression (13), death (213. Body weight change (g) GD 6-20: 29.3 (reduced; p<0.001); n=11
500 mg/kg bw /d: rales (87), dyspnea (60), motor depression (73), death (53). Body weight change (g) GD 6-20: 30.5 (reduced; p<0.001), n=9
Effect levels (maternal animals)
- Dose descriptor:
- LOAEL
- Effect level:
- 187.5 mg/kg bw/day
- Basis for effect level:
- other: maternal toxicity
Results (fetuses)
- Details on embryotoxic / teratogenic effects:
- Embryotoxic / teratogenic effects:no effects
Details on embryotoxic / teratogenic effects:
No effect on perinatal loss, pup weight, but trend at the high dose level without gaining a level of statistical significance. No malformations.
Effect levels (fetuses)
- Dose descriptor:
- NOAEL
- Effect level:
- 250 mg/kg bw/day
- Basis for effect level:
- other: teratogenicity
Fetal abnormalities
- Abnormalities:
- not specified
Overall developmental toxicity
- Developmental effects observed:
- not specified
Any other information on results incl. tables
2-MP; development
Dose |
No dams |
No. implants |
No. live pups |
Perinatal loss (%) (means) |
Pup weight (g) |
||
PD1 |
PD6 |
PD1 |
PD6 |
||||
0 |
18 |
12.8 |
12.1 |
11.4 |
10.7 |
7.1 |
14.2 |
187.5 |
11 |
12.4 |
11.3 |
11.2 |
10.7 |
7.0 |
14.0 |
250 |
9 |
13.4 |
12.0 |
11.8 |
19.9 |
7.0 |
13.7 |
PD1, PD 6 = postnatal day 1 and 6, respectively
Skeletal findings 2-MP (T02102)
Skeletal findings |
Dose level (mg(kg bw and day) |
||
0 |
187.5 |
250 |
|
No pups (litters) examined |
36 (18) |
22 (11) |
16 (8) |
Rudimentary lumbar rib |
10 (7) |
10 (8) |
3 (2) |
Bilobed centrum |
3 (3) |
2 (2) |
1 (1) |
Extra sternebra |
2 (2) |
1 (1) |
0 |
Applicant's summary and conclusion
- Conclusions:
- In a Chernoff/Kavlock screening assay, 2-methylpentanoic acid was not reprotoxic in female Sprague Dawley rats at maternally toxic doses
- Executive summary:
2-methylpentanoic acid was tested in a Chernoff/Kavlock screening assay using pregnant Sprague Dawley rats (20 controls, treated rats 15 per dose level). The test substance was administered in corm oil (1 mL/kg bw) at 187.5 and 250 mg/kg bw. The doses were selected based on the maternal toxicity observed in non-gravid females in preceding studies. Clinical signs, body weight, and pre-implantation loss in dams was recorded. Foetal weight at birth and at day 6 was recorded. Histopathology on the pups was performed on a screening level as follows:
Dead pups: soft tissue alterations
Externally malformed pups: skeletal and/or soft tissue alterations as indicated by the gross findings
Surviving pups: skeletal alterations in 2 pups per litter (one per sex).The results indicate maternal toxicity at both dose levels, with mortalities of 13% and 27%, respectively, and with clinical signs and significantly reduced body weight gain during pregnancy in the surviving dams. Peri-natal loss and pup weight at birth or postnatal day 6 was not affected; there was a trend for effects at the high dose level without gaining statistical significance. Treatment-related malformations were not reported (Narotsky, Francis, and Kavlock, 1994).
The study protocol used was a screening protocol for developmental toxicity. The study is not comparable with current screening methods (OECD 412 or 422) or the specific developmental toxicity protocol (OECD 414). It can, however, be used in a weight of evidence approach because the publication reports the results for a total of 15 acids (13 of these branched) what allows to read across the results to isovaleric acid. Other than isovaleric acid, 2-methylpentanoic acid bears the methyl group at the 2-position. The authors found developmental toxicity only with those acids bearing a side chain at the 2-position, with a side chain lengths of 2 or more carbons.
The study is considered to be valid with restrictions.
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.