Registration Dossier

Administrative data

Description of key information

L-Cystine was found to be non-irritating in in-vivo skin and eye irritation tests.

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
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: OECD Guideline study performed under GLP conditions
Qualifier:
according to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Species:
rabbit
Strain:
New Zealand White
Type of coverage:
semiocclusive
Preparation of test site:
shaved
Vehicle:
water
Controls:
not required
Amount / concentration applied:
0,5 g
Duration of treatment / exposure:
4 hours
Observation period:
72 hours after patch removal
Number of animals:
3
Details on study design:
The untreated side served as control.
Irritation parameter:
erythema score
Basis:
animal #1
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
erythema score
Basis:
animal #2
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
erythema score
Basis:
animal #3
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
edema score
Basis:
animal #1
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
edema score
Basis:
animal #2
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
edema score
Basis:
animal #3
Time point:
other: 24 - 72 h
Score:
ca. 0
Other effects:
no specific findings
Interpretation of results:
not irritating
Remarks:
Migrated information Criteria used for interpretation of results: OECD GHS
Conclusions:
Under the conditions of the present study, the single dermal application of the test item L-Cystine to three rabbits at a dose of 0.5 g showed neither irritant nor corrosive effects.
Executive summary:

Under the conditions of the present study, the single dermal application of the test item L-Cystine to three rabbits at a dose of 0.5 g showed neither irritant nor corrosive effects.

Neither mortalities nor significant clinical signs of toxicity were observed.

In conformity with the EC criteria for classification and labelling requirements for dangerous substances and preparations according to Annex VI of Commission Directive 2001/59/EC, the test item L-Cystine does not have to be classified and has no obligatory labelling requirement for skin irritation.

According to Annex I of Regulation (EC) 1272/2008, the test item L-Cystine does not have to be classified and has no obligatory labelling requirement for skin irritation.

According to GHS (Globally Harmonized Classification System), the test item L-Cystine has no obligatory labelling requirement for skin irritation.

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
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: OECD Guideline study performed under GLP conditions
Qualifier:
according to
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Species:
rabbit
Strain:
New Zealand White
Vehicle:
unchanged (no vehicle)
Controls:
not required
Amount / concentration applied:
0,1 g
Duration of treatment / exposure:
The treated eye was not rinsed 24 hours after the application.
Observation period (in vivo):
The animals were observed for 72 hours after dosing.
Number of animals or in vitro replicates:
3
Details on study design:
The untreated contralateral eye served as control.
Irritation parameter:
conjunctivae score
Basis:
animal #1
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
conjunctivae score
Basis:
animal #2
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
conjunctivae score
Basis:
animal #3
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
chemosis score
Basis:
animal #1
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
chemosis score
Basis:
animal #2
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
chemosis score
Basis:
animal #3
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
iris score
Basis:
animal #1
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
iris score
Basis:
animal #2
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
iris score
Basis:
animal #3
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
cornea opacity score
Basis:
animal #1
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
cornea opacity score
Basis:
animal #2
Time point:
other: 24 - 72 h
Score:
ca. 0
Irritation parameter:
cornea opacity score
Basis:
animal #3
Time point:
other: 24 - 72 h
Score:
ca. 0
Other effects:
Neither mortality nor significant clinical signs of toxicity were observed.
Interpretation of results:
not irritating
Remarks:
Migrated information Criteria used for interpretation of results: OECD GHS
Conclusions:
Under the conditions of the present study, a single ocular application of the test item L-Cystine at a dose of 0,1 g produced irritant effects, which were fully reversible within 72 hours.
Executive summary:

Under the conditions of the present study, a single ocular application of the test item L-Cystine to rabbits at a dose of 0.1 g produced irritant effects, which were fully reversible within 72 hours. Neither mortalities nor significant clinical signs of toxicity were observed.

In conformity with the EC criteria for classification and labelling requirements for dangerous substances and preparations according to Annex VI of Commission Directive 2001/59/EC, the test item L-Cystine has no obligatory labelling requirement for eye irritation.

According to Annex I of Regulation (EC) 1272/2008, the test item L-Cystine has no obligatory labelling requirement for eye irritation.

According to GHS (Globally Harmonized Classification System) the test item L-Cystine has no obligatory labelling requirement for eye irritation.

Neither mortality nor significant clinical signs of toxicity were observed.

The test item L-Cystine has no obligatory labelling requirement for eye irritation.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Under the conditions of an OECD 404 study, the single dermal application of the test item L-Cystine to three rabbits at a dose of 0.5 g showed neither irritant nor corrosive effects. Neither mortalities nor significant clinical signs of toxicity were observed.

Under the conditions of an OECD 405 study, a single ocular application of the test item L-Cystine to rabbits at a dose of 0.1 g produced irritant effects, which were fully reversible within 72 hours. Neither mortalities nor significant clinical signs of toxicity were observed.


Justification for selection of skin irritation / corrosion endpoint:
In vivo guideline study according OECD 404.

Justification for selection of eye irritation endpoint:
In vivo guideline study according OECD 405.

Justification for classification or non-classification

L-Cystine has no obligatory labelling requirement for skin irritation.

L-Cystine has no obligatory labelling requirement for eye irritation.