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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 200-274-3 | CAS number: 56-45-1
- 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
Endpoint summary
Administrative data
Description of key information
Key value for chemical safety assessment
Acute toxicity: via oral route
Link to relevant study records
- Endpoint:
- acute toxicity: oral
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: GLP guideline study with acceptable restrictions
- Qualifier:
- according to guideline
- Guideline:
- other: Kouseisho-21 Yakuhatsu-424
- GLP compliance:
- yes
- Test type:
- standard acute method
- Limit test:
- yes
- Species:
- rat
- Strain:
- Sprague-Dawley
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- - Sprague-Dawley strain SPF rats [Crl:CD(SD)]
- Test period: 2007.10.17 - 2008.01.31 - Route of administration:
- oral: gavage
- Vehicle:
- not specified
- Doses:
- 2000 mg/kg b.w.
- No. of animals per sex per dose:
- 5
- Control animals:
- not specified
- Details on study design:
- L-Serine was administrated once each to groups of 5 males and 5 female Sprague-Dawley strain SPF rats [Crl:CD(SD)] at one dose level of
2,000 mg/kg. - Sex:
- male/female
- Dose descriptor:
- LD50
- Effect level:
- > 2 000 mg/kg bw
- Based on:
- test mat.
- Mortality:
- No death occurred in males and females in any test article group. Therefore, the lethal dose level was estimated to be higher than 2,000 mg/kg for
L-serine. - Clinical signs:
- other: There were no abnormalities in clinical signs in any male or female animal during the observation period.
- Gross pathology:
- There were no abnormalities in the external appearance, or in organs/tissues in the cranial, thoracic or abdominal regions in any male or female
animals. - Interpretation of results:
- study cannot be used for classification
- Remarks:
- Migrated information
- Conclusions:
- Based on the results of the study report, it was estimated that the toxicity of L-serine was extremely low.
Reference
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed
Acute toxicity: via dermal route
Endpoint conclusion
- Endpoint conclusion:
- no study available
Additional information
Acute oral toxicity
In an acute oral toxicity GLP study according to OECD 420, groups of Sprague-Dawley rats (5/sex) were given a single oral dose of test item at doses of 2000 mg/kg bw. All animals survived and no toxicity (differences in body weight, feed consumption, clinical observations, gross organ necroscopy) could be observed. The resulting oral LD50 is >2000 mg/kg bw.
This result was confirmed in another published acute oral toxicity study according to OCED420 (van de Mortel 2010).
However, the true LD50 is much higher. This is clearly demonstrated by the results of a 13 -week subchronic oral toxicity study published by Kaneko et al. (2009) in which 3000 mg/kg bw was the NOEL for L-serine. In an older study which was performed prior to GLP the LD50 was determined to be 14 (12.8 -15.3) g/kg bw. The study was well documented and acceptable for assessment.
These results clearly indicate the very low acute toxicity of this amino acid.
Acute inhalative toxicity
No data on acute inhalation toxicity for L-serine is available. Significant exposure of humans via inhalation is unlikely taking into account the vapour pressure and the particle size of the substance, while exposure of humans via skin contact is likely.
However, there is an in vivo OECD 403 GLP-guideline study available for L-threonine. L-Serine and L-threonine belong to the group of polar amino acids as their side chains are polar but not charged. Their chemical structure is very similar with both having the same set of functional groups. The only difference between the two molecules is that L-threonine contains one additional methyl group in the amino acid side chain. Both substances have a low molecular weight, nearly identical logKow values (~-3) and also very similar pKa values. In addition to the similar physico-chemical properties also the toxicological and ecotoxicological/fate data indicate a very low toxicity (if any) of both substances for the environment (toxicity for aquatic organisms) as well as a very low toxicity for human health (toxicity to experimental animals). The absence of significant toxicity is not surprising as both substances are ubiquitous occurring substances (also in body fluids of animals and humans) which serve as building blocks for protein synthesis in all animals (including humans). Due to the very similar chemical structure resulting in very similar physico-chemical properties and a very low (eco)toxicity profile of both substances it is justified to fulfil the data requirement with regard to inhalative toxicity for L-serine by a read-across approach from available data for L-threonine.
The aim of the available limit test with L-threonine was to obtain information on the acute inhalative toxicity following a single 4 hour exposure of rats. No signs of toxicity were observed at 5.15 +/-0.1 mg test substance/l.
Acute dermal toxicity
No data on acute dermal toxicity for L-serine is available. The substance is of very low systemic toxicity as no systemic effects were observed in limit acute oral toxicity studies (2000 mg/kg bw) as well as in repeated dose toxicity studies (3000 mg/kg bw). The LD50 for the acute oral toxicity was 14000 mg/kg bw. Due to this very low toxicity and the fact that L-serine with high water solubility and a log P value well below 0 may be too hydrophilic to cross the lipid rich environment of the stratum corneum it is highly improbable that an acute dermal toxicity study would result in any toxicity. Therefore and for animal welfare reasons no further acute dermal toxicity study is justified and the dermal LD50 is assumed to be > 2000 mg/kg bw.
Justification for classification or non-classification
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.