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EC number: 200-795-6 | CAS number: 73-22-3
- 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
Skin sensitisation
Administrative data
- Endpoint:
- skin sensitisation: in vivo (LLNA)
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 2007-02-14 to 2007-02-21
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- other: GLP study according to OECD guideline 429 (adopted 2002)
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 2 007
- Report date:
- 2007
Materials and methods
Test guideline
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
- Deviations:
- no
- GLP compliance:
- yes
- Type of study:
- mouse local lymph node assay (LLNA)
Test material
- Reference substance name:
- L-tryptophan
- EC Number:
- 200-795-6
- EC Name:
- L-tryptophan
- Cas Number:
- 73-22-3
- Molecular formula:
- C11H12N2O2
- IUPAC Name:
- L-tryptophan
- Test material form:
- solid: particulate/powder
- Remarks:
- migrated information: powder
Constituent 1
In vivo test system
Test animals
- Species:
- mouse
- Strain:
- CBA
- Sex:
- female
- Details on test animals and environmental conditions:
- Source: Harlan Italy s.r.l.
Weight: 16-20 g
Age: ca. 7-8 weeks
Acclimatisation period: 5 days
Housing: individually in polycarbonate cages with a stainless steel mesh lid
Diet: 4RF18 ad libitum
Water: ad libitum
Environmental conditions:
Temperature (°C): 22 ± 2
Relative humidity (%): 55 ± 15
Photoperiod (hrs dark / hrs light): 12 / 12 by fluorescent tubes
Air changes (per hr): 15-20
Study design: in vivo (LLNA)
- Vehicle:
- acetone/olive oil (4:1 v/v)
- Concentration:
- 0 (vehicle controls), 5, 10 and 25% (w/v)
- No. of animals per dose:
- 5 females
- Details on study design:
- Each group of mice was treated for 3 consecutive days by topical application to the dorsal surface of each ear with 25 μl of the appropriate concentration of the test or control item. The application volume was spread over the entire dorsal surface of the ear. Animals of the negative control group received the selected vehicle only, given by the same route of administration as the test item. Five days after the first treatment, 20 μCi of [3]H-methyl thymidine diluted in sterile phosphate buffered saline were administered to each animal by intravenous injection in the tail vein. The dose volume was 250 μl. Approximately five hours later, the animals were sacrificed and the auricular lymph nodes were excised from each animal. 3H-methyl thymidine incorporation was measured by a β-scintillation counter in the prepared cell suspensions.
- Positive control substance(s):
- hexyl cinnamic aldehyde (CAS No 101-86-0)
- Statistics:
- The significance of the differences amongst groups was assessed by analysis of variance. Differences between the treated group and the control group were assessed by Dunnett's test using a pooled error variance. The homogeneity of the data was verified by Bartlett's test before Dunnett's test. If data were found to be inhomogeneous a Modified t test (Cochran and Cox) was applied. The mean values, standard deviations and statistical analysis were calculated from the actual values in the computer without rounding off.
Results and discussion
- Positive control results:
- In the group treated with the positive control item, the increase in [3]HTdR incorporation was clearly observed. The calculated SI was > 3 at the tested dose-level (SI = 20.45).
In vivo (LLNA)
Resultsopen allclose all
- Parameter:
- SI
- Remarks on result:
- other: 5% group: 0.77 10% group: 0.7 25% group: 1.64 positive control group: 20.45
- Parameter:
- other: disintegrations per minute (DPM)
- Remarks on result:
- other: Mean dpm/animal or dpm/node: vehicle control group: 224 / 112.2 5% group: 171.4 / 86 10% group: 155.8 / 78.2 25% group: 366.6 / 192.4 positive control group: 4580.6 / 2290.6
Applicant's summary and conclusion
- Interpretation of results:
- not sensitising
- Remarks:
- Migrated information Criteria used for interpretation of results: EU
- Conclusions:
- The potential of L-tryptophan to induce skin sensitisation was assessed by using the murine local lymph node assay in a GLP study according to OECD guideline 429. Five groups, each of 5 female mice, were treated with the test item at concentrations of 5, 10 and 25%, with the reference item alpha-Hexylcinnamaldehyde at the concentration of 25%, and with the vehicle alone (Acetone/olive oil 4:1). No statistically significant increase in [3]HTdR incorporation was observed in animals treated with the test item when compared to the negative control group. The calculated SI was lower than 3 at all dose-levels tested. Reliability check was positive as expected. No reaction, indicating a potential systemic effect, was observed after treatment at any of the dose-levels investigated. No signs of local irritation were observed at application sites.
Therefore, it can be concluded that L-tryptophan did not elicit any sensitisation response.
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