Registration Dossier
Registration Dossier
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: 433-730-7 | CAS number: 23926-51-4 L-THREONINETHYLESTER
- 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
Skin sensitisation
Link to relevant study records
- Endpoint:
- skin sensitisation: in vivo (non-LLNA)
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- May 12, 2000 - June 23, 2000
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Remarks:
- Minor deviations from protocol: acclimatisation period was slightly longer than envisaged in the protocol, and it was not considered likely to compromise the study integrity. The references in the protocol to study days from Day 7 onward are one day later than actually occurred in the study.
- Reason / purpose for cross-reference:
- reference to same study
- Reason / purpose for cross-reference:
- reference to other study
- Qualifier:
- according to guideline
- Guideline:
- EU Method B.6 (Skin Sensitisation)
- Deviations:
- yes
- Remarks:
- acclimatisation period, and references to study days.
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 406 (Skin Sensitisation)
- Deviations:
- yes
- Remarks:
- acclimatisation period, and references to study days.
- Qualifier:
- according to guideline
- Guideline:
- EPA OPPTS 870.2600 (Skin Sensitisation)
- Deviations:
- yes
- Remarks:
- acclimatisation period, and references to study days.
- Principles of method if other than guideline:
- NA
- GLP compliance:
- yes (incl. QA statement)
- Type of study:
- guinea pig maximisation test
- Justification for non-LLNA method:
- Study was performed before implementation of the LLNA test guideline.
- Specific details on test material used for the study:
- SOURCE OF TEST MATERIAL
- Source and lot/batch number of test material: 142-576-6
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: < 10 °C when not in use
TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Final dilution of a dissolved solid, stock liquid or gel: 1% m/v in purified water up to the maximum practical concentration of
25% m/v in purified water - Species:
- guinea pig
- Strain:
- Dunkin-Hartley
- Sex:
- female
- Details on test animals and environmental conditions:
- TEST ANIMALS
- Source: D Hall Ltd, Burton
- Age at study initiation: 4 to 6 weeks
- Weight at study initiation: 341 to 392g
- Housing: suspended polypropylene cages with open tops, solid floors and stainless steel mesh front panels, 5 animals/cage
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 7 days
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 25°C
- Humidity (%): 40 to 70% RH
- Air changes (per hr): 14 air changes per hour
- Photoperiod (hrs dark / hrs light): 12 hours illumination by fluorescent strip-lights
IN-LIFE DATES: From 3 April 2000 to 23 June 2000 - Route:
- intradermal
- Vehicle:
- water
- Concentration / amount:
- 4% m/v Threonineethylester
- Day(s)/duration:
- 2
- Route:
- epicutaneous, occlusive
- Vehicle:
- water
- Concentration / amount:
- 65% m/m Threonineethylester
- Day(s)/duration:
- 10
- Route:
- epicutaneous, occlusive
- Vehicle:
- water
- Concentration / amount:
- 10 and 20%
- Day(s)/duration:
- 1 day
- No. of animals per dose:
- Number of animals in test group: 10
Number of animals in negative control group: 5 - Details on study design:
- RANGE FINDING TESTS:
The first screening test (intradermal injection phase of induction):
- vehicle and six formulations.
- range of concentrations from 1% m/v in purified water up to the maximum practical concentration of 25%m/v in purifed water, 0.1mL per site
-Site: scapular zone of the denuded dorsum
The second screening test (topical application phase of induction):
- four formulations
- range of concentrations: from 20 to 65% m/m in purified water, approx 1mL
- preparation: intradermal injection of FCA into the suprascular dorsom 11 days prior to application of the test formualtion
- application: occluded, four 25x25mm lint pads
-Site: suprascapular dorsum
The third screening test (topical application at challenge):
- four formulations
- range of concentaiotns: from 1 to 20% m/m in purified water, approx 1mL
- preparation: intradermal injection of FCA into the suprascular dorsom 18 days prior to application of the test formualtion
- application: occluded, four 25x25mm lint pads
MAIN STUDY
A1. INDUCTION EXPOSURE-intradermal
- No. of exposures: 3 paired injections
- Exposure period: NA
- Test groups: FCA, L-TEE 4%m/v in purified water, L-TEE 4%m/v in FCA
- Control group: FCA, purifed water, 50% v/v purified water in FCA
- Site: Dorsal : Anterior, Middle, Posterior
- Frequency of applications: once
- Duration: NA
- Concentrations: 0.1 mL per site
A2. INDUCTION EXPOSURE-topical
- No. of exposures: 1
- Exposure period: 48 hours
- Test groups: 65% m/m L-TEE in purifed water
- Control group: purifed water alone
- Site: Dorsal
- Frequency of applications: once
- Duration: 48 hours
- Concentrations: 2 mL
B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: Day 21
- Exposure period: 24 hours
- Test groups: no
- Control group: 20% m/m L-TEE in purifed water, 10% m/m L-TEE in purifed water
- Site: left flank, right flank
- Concentrations: 1 mL
- Evaluation (hr after challenge): 24 and 48 hours after removal of the dressings - Challenge controls:
- None
- Positive control substance(s):
- no
- Positive control results:
- NA
- Reading:
- 1st reading
- Hours after challenge:
- 24
- Group:
- test chemical
- Dose level:
- 10 %
- No. with + reactions:
- 7
- Total no. in group:
- 10
- Clinical observations:
- 1, 1, 1S, 1HQ, 1SQ, 1, 2S
- Remarks on result:
- other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 10 %. No with. + reactions: 7.0. Total no. in groups: 10.0. Clinical observations: 1, 1, 1S, 1HQ, 1SQ, 1, 2S.
- Reading:
- 1st reading
- Hours after challenge:
- 24
- Group:
- test chemical
- Dose level:
- 20 %
- No. with + reactions:
- 10
- Total no. in group:
- 10
- Clinical observations:
- 2HS, 2, HES#, 2, 1, 2HQ, 2SQ, 2SQ, 1, 2SH. #: Erythema score not possible to assess due to hardened, scabbed test site
- Remarks on result:
- other: see Remark
- Remarks:
- Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 20 %. No with. + reactions: 10.0. Total no. in groups: 10.0. Clinical observations: 2HS, 2, HES#, 2, 1, 2HQ, 2SQ, 2SQ, 1, 2SH. #: Erythema score not possible to assess due to hardened, scabbed test site.
- Reading:
- 2nd reading
- Hours after challenge:
- 48
- Group:
- test chemical
- Dose level:
- 10 %
- No. with + reactions:
- 9
- Total no. in group:
- 10
- Clinical observations:
- 1HQ, 0QS, 0Q, 0Q, 1QS, 2QS, 0Q, 1Q, 2QS
- Remarks on result:
- other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 10 %. No with. + reactions: 9.0. Total no. in groups: 10.0. Clinical observations: 1HQ, 0QS, 0Q, 0Q, 1QS, 2QS, 0Q, 1Q, 2QS.
- Reading:
- 2nd reading
- Hours after challenge:
- 48
- Group:
- test chemical
- Dose level:
- 20 %
- No. with + reactions:
- 10
- Total no. in group:
- 10
- Clinical observations:
- 1QS, 1HQ, HES#, 1QS, 1Q, 1HQS, 2QS, 1QS, 1Q, 2QS. #: Erythema score not possible to assess due to hardened, scabbed test site.
- Remarks on result:
- other: see Remark
- Remarks:
- Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 20 %. No with. + reactions: 10.0. Total no. in groups: 10.0. Clinical observations: 1QS, 1HQ, HES#, 1QS, 1Q, 1HQS, 2QS, 1QS, 1Q, 2QS. #: Erythema score not possible to assess due to hardened, scabbed test site. .
- Reading:
- 1st reading
- Hours after challenge:
- 24
- Group:
- negative control
- Dose level:
- 10 %
- No. with + reactions:
- 0
- Total no. in group:
- 5
- Clinical observations:
- no observations
- Remarks on result:
- other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 10 %. No with. + reactions: 0.0. Total no. in groups: 5.0.
- Reading:
- 1st reading
- Hours after challenge:
- 24
- Group:
- negative control
- Dose level:
- 20 %
- No. with + reactions:
- 0
- Total no. in group:
- 5
- Clinical observations:
- no observations
- Remarks on result:
- other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 20 %. No with. + reactions: 0.0. Total no. in groups: 5.0.
- Reading:
- 2nd reading
- Hours after challenge:
- 48
- Group:
- negative control
- Dose level:
- 10 %
- No. with + reactions:
- 0
- Total no. in group:
- 5
- Clinical observations:
- no observations
- Remarks on result:
- other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 10 %. No with. + reactions: 0.0. Total no. in groups: 5.0.
- Reading:
- 2nd reading
- Hours after challenge:
- 48
- Group:
- negative control
- Dose level:
- 20 %
- No. with + reactions:
- 1
- Total no. in group:
- 5
- Clinical observations:
- no observations
- Remarks on result:
- other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 20 %. No with. + reactions: 1.0. Total no. in groups: 5.0. Clinical observations: 0D.
- Reading:
- 2nd reading
- Hours after challenge:
- 48
- Group:
- positive control
- Dose level:
- 4% (intradermal), 60% (topocal) - 60 and 30% for challenge phase
- No. with + reactions:
- 8
- Total no. in group:
- 10
- Clinical observations:
- No information
- Remarks on result:
- positive indication of skin sensitisation
- Interpretation of results:
- sensitising
- Conclusions:
- The skin sensitisation potential of L-TEE was evaluated using the challenge procedure. The study was performed following Magnusson and Kligman procedures. The results indicated that all ten animals gave a positive response indicative of delayed contact hypersensitivity.
Based on the results of this study, the level of positive responses to challenge with L-TEE was sufficient for the risk phrase R43 “May cause sensitisation by skin contact” to be required under the terms of the General Classification and Labelling Requirements for Dangerous Substances and Preparations, as stated in Annex V to Commission Directive 96/54/EC. - Executive summary:
This study was conducted to assess the potential of L-TEE to elicit skin sensitisation (delayed contact hypersensitivity) in the guinea pig following Magnusson and Kligman procedures. Ten test and five control animals were used in this study. Based on the results of the preliminary studies, the following dose levels were chosen:
- Intradermal injection: 4% m/v L-TEE in purified water and/or adjuvant
- Topical induction: 65% m/m L-TEE in purified water
- Challenge application: 10 and 20% m/m L-TEE in purified water
L-TEE elicited a positive response, indicative of skin sensitisation (delayed contact hypersensitivity) in all ten test animals following the challenge application.
Based on the results of this study, the level of positive responses to challenge with L-TEE was sufficient for the risk phrase R43 “May cause sensitisation by skin contact”.
Reference
None
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed (sensitising)
- Additional information:
The skin sensitisation potential of L-TEE was evaluated using the challenge procedure. The study was performed following Magnusson and Kligman procedures (OECD 406). The results indicated that all ten animals gave a positive response indicative of delayed contact hypersensitivity.
Justification for selection of skin sensitisation endpoint:
Key study
Respiratory sensitisation
Endpoint conclusion
- Endpoint conclusion:
- no study available
Justification for classification or non-classification
Based on the results of the skin sensitisation potential study, the level of positive responses to challenge with L-TEE was sufficient for the risk phrase R43 “May cause sensitisation by skin contact” to be required under the terms of the General Classification and Labelling Requirements for Dangerous Substances and Preparations, as stated in Annex V to Commission Directive 96/54/EC.
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.
