Registration Dossier

Administrative data

Description of key information

L-Threonine mother liquor was tested for skin irritation in a GLP study according to OECD guideline 404. Neither erythema nor edema was seen in any rabbit (PDII = 0) and there were also no clinical signs of systemic toxicity.
L-Threonine mother liquor was tested for eye irritation in a GLP study according to OECD guideline 405. The primary irritation index was 0, i.e. the test substance caused no eye irritation. There were also no clinical signs of systemic toxicity.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records
Reference
Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1993
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP study according to OECD guideline 404 (1981)
Qualifier:
according to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Deviations:
no
Qualifier:
according to
Guideline:
other: Commission Directive 92/32/EEC
GLP compliance:
yes
Species:
rabbit
Strain:
other: White russian (Albino)
Details on test animals and environmental conditions:
TEST ANIMALS
-Source: ASTA Medica AG, Halle, Germany
-Age at study initiation: 10 months
-Weight at study initiation: 2430 – 2800 g
-Housing: individually
-Certified diet ad libitum
-Tap water ad libitum
-Acclimation period: At least one day under test conditions before application of the test substance

ENVIRONMENTAL CONDITIONS
According to guideline
Type of coverage:
occlusive
Preparation of test site:
shaved
Vehicle:
unchanged (no vehicle)
Controls:
other: Opposite area of the dorsal skin was treated in the same way but without test substance
Amount / concentration applied:
TEST MATERIAL
-Amount(s) applied: 0.5 mL liquid test item
-Concentration: undiluted liquid test substance
Duration of treatment / exposure:
4 h
Observation period:
1, 24, 48, and 72 h after patch removal
Number of animals:
2 females and 1 male
Details on study design:
One day before treatment the dorsal skin area was clipped. 0.5 mL of the test substance was given on the left of the vertebral column, covered with a patch (6.25 cm2) and bandaged for complete occlusion. After 4 h exposure the dressing was removed and the remaining test substance was washed off.
Scoring system according to Guideline.
The examination included also the occurrence of clinical symptoms (systemic toxicity).
Duration of observation period: 3 days.
Irritation parameter:
primary dermal irritation index (PDII)
Basis:
mean
Time point:
other: 1 - 72 h
Score:
0
Max. score:
4
Remarks on result:
other: No erythema, eschar and edema in any animal at any time point.
Irritant / corrosive response data:
Neither erythema nor edema was seen in any rabbit.
Other effects:
No clinical signs of systemic toxicity were observed in the animals during the study.
Interpretation of results:
not irritating
Remarks:
Migrated information Criteria used for interpretation of results: OECD GHS
Conclusions:
L-Threonine mother liquor was tested for skin irritation in a GLP study according to OECD guideline 404. Neither erythema nor edema was seen in any rabbit (PDII = 0) and there were also no clinical signs of systemic toxicity.
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records
Reference
Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1993
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP study according to OECD guideline 405 (1987)
Qualifier:
according to
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
Deviations:
no
Qualifier:
according to
Guideline:
other: Commission Directive 92/32/EEC
GLP compliance:
yes
Species:
rabbit
Strain:
other: White russian (Albino)
Details on test animals or tissues and environmental conditions:
TEST ANIMALS
-Source: ASTA Medica AG, Halle, Germany
-Age at study initiation: 12 months
-Weight at study initiation: 2070 – 3410 g
-Housing: individually
-Certified diet ad libitum
-Tap water ad libitum
-Acclimation period: At least one day under test conditions before application of the test substance

ENVIRONMENTAL CONDITIONS
According to guideline
Vehicle:
unchanged (no vehicle)
Controls:
other: The other eye was not treated and acted as control.
Amount / concentration applied:
TEST MATERIAL
-Amount: 0.1 mL
-Concentration (if solution): undiluted
Duration of treatment / exposure:
eyes were not rinsed
Observation period (in vivo):
Scoring 1, 24, 48, and 72 h after instillation
Number of animals or in vitro replicates:
1 female and 2 males
Details on study design:
Application of 0.1 mL of the test substance into the conjunctival sac of the right eye.
Scoring: According to Guideline
Tool used to assess score: Varta Cliptrix diagnostic-lamp
Attention was paid also on the occurrence of clinical symptoms (systemic toxic effects)
Irritation parameter:
overall irritation score
Basis:
mean
Time point:
other: 72 h
Score:
0
Max. score:
110
Remarks on result:
other: In one animal hyperemia of the conjunctiva was recorded at the application day.
Irritant / corrosive response data:
The primary irritation index was zero, i.e. the test substance caused no eye irritation in rabbits.
Other effects:
No clinical signs of systemic toxicity were observed in the animals during the study.
Interpretation of results:
not irritating
Remarks:
Migrated information Criteria used for interpretation of results: OECD GHS
Conclusions:
L-Threonine mother liquor was tested for eye irritation in rabbits in a GLP study according to OECD guideline 405. The primary irritation index was zero, i.e. the test substance caused no eye irritation. There were also no clinical signs of systemic toxicity.
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Skin irritation was tested in a GLP study according to OECD guideline 404 (adopted 1981). Two female and one male rabbit received dermal occlusive application of 0.5 mL of the undiluted test item to the shaved intact left flank. The duration of treatment was four hours and scoring of skin reactions was performed 1, 24, 48 and 72 hours after removal of the dressing. Neither erythema nor edema was seen in any rabbit (PDII = 0) and there were also no clinical signs of systemic toxicity.

Eye irritation was tested in a GLP study according to OECD guideline 405 (adopted 1987). One female and two male rabbits received each instillations of 0.1 mL of the undiluted test item into the conjunctival sac; no washing of the eyes was performed. Eyes were scored 1, 24, 48 and 72 hours after instillation. The primary irritation index was 0, i.e. the test substance caused no eye irritation. There were also no clinical signs of systemic toxicity.

Justification for classification or non-classification