N-(N6-trifluoroacetyl-L-lysyl)-L-proline

Endpoint summary

Description of key information

N6-Trifluoroacetyl-L-IysyI-L-proline has no sensitizing properties on the skin of guinea pigs in a study conducted according to OECD TG 406. Thus, the test item does not need to be classified according to Regulation (EC) No 1272/2008 (CLP) and the Globally Harmonized System for Classification and Labelling of Chemicals (GHS).

The skin sensitizing proerties of the test item were investigated in a second study conducted according to OECD TG 406. Following epidermal challenge, neither treated nor control animals showed any changes at the exposed skin. In the animals of the control and treatment groups systemic toxic effects could not be detected. ε-Trifluoroacetyl-L-lysyl-L-proline has no sensitizing properties on the skin of guinea pigs

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1997-06-03 to 1997-08-20

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Version / remarks:

1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

Version / remarks:

1996

Deviations:

no

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

A valid GPMT conducted according to guideline is available, which is reliable without restrictions and adequate for classification and labelling purposes. Potency estimation is not mandatory when existing guideline and GLP conforming data are available, which were conducted before the new annex of the REACH Regulation entered into force. Moreover, no indication for skin sensitisation was observed in this study, thus, no dose response information is needed. For this reason and for reasons of animal welfare no additional LLNA was conducted.

Species:

guinea pig

Strain:

other: HsdPOC: DH

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Females (if applicable) nulliparous and non-pregnant: not specified
- Age at study initiation: Males 8 weeks; females 8 weeks
- Weight at study initiation: Males 397-463 g; females 399-494 g
- Housing: individually, in Macrolon cages type IV with Biological bedding, Hugro® 560, supplied by Hugro Vertrieb Deutschland G. Leugers, D-48268
Greven
- Diet (e.g. ad libitum): Standard diet ad libitum, ssniff® Ms-Z, complete diet for guinea pigs - breeding, supplied by ssniff Spezialdiaten GmbH, D-59494 Soest
- Water (e.g. ad libitum): ad libitum, Water was provided in drinking water quality from the Stadtwerke Halle (twice weekly ascorbic acid (vitamin C) was added), using a time switched drinking water system with drinking nipples.
- Acclimation period: At least five days
- Indication of any skin lesions: no

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19.5-21.5
- Humidity (%): 45-70
- Photoperiod (hrs dark / hrs light): 12/12

Route:

intradermal and epicutaneous

Vehicle:

physiological saline

Concentration / amount:

5% and 50%

Day(s)/duration:

Day 1 intradermal application, Day 8 epicutaneous application

Adequacy of induction:

non-irritant substance, but skin pre-treated with 10% SDS

Route:

epicutaneous, occlusive

Vehicle:

physiological saline

Concentration / amount:

50%

Day(s)/duration:

Day 22 for 24 h

No. of animals per dose:

Number of animals in test group: 10
Number of animals in negative control group: 12

Details on study design:

RANGE FINDING TESTS:
In preliminary tests, the concentrations for the lntracutaneous and for the epidermal applications during the induction phase as well as a non-irritating concentration for the epidermal application during the challenge phase were determined. The concentrations were:
induction phase: intradermal, non-irritating: 5%
epidermal, non-irritating: 50%
challenge phase: epidermal, non-irritating: 50%
MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: total 6 for intrdermal 1 for epicutaneous
- Exposure period: Day 1 to 8 and 8 to 22
- Test groups: intradermal
2 x FCA/physiological saline solution (1:1)
2 x test substance preparation
2 x test substance preparation/FCA (1:1)
epicutaneous
1 x 50% substance preparation
- Control group: Identical treatment, however, the vehicle was used instead of the test substance preparation.
- Site: Scapular area
- Frequency of applications: each applied once
- Concentrations: 5%/50%

B. CHALLENGE EXPOSURE
- No. of exposures: one
- Day(s) of challenge: 22
- Exposure period: 24h
- Test groups: all test groups (intrdermal and epicutaneous)
- Control group: dentical to treatment of animals of the test substance group. The control animals Nos. 1 - 3 and 4 - 6 were used.
- Site: Right flank (vehicle) Left flank (test substance preparation)
- Concentrations: 50%
- Evaluation (hr after challenge): 24 and 48 h

Positive control substance(s):

no

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

50%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 30%. No with. + reactions: 0.0. Total no. in groups: 10.0.

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

50%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 30%. No with. + reactions: 0.0. Total no. in groups: 10.0.

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

0%

No. with + reactions:

0

Total no. in group:

12

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 30%. No with. + reactions: 0.0. Total no. in groups: 12.0.

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

0%

No. with + reactions:

0

Total no. in group:

12

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 30%. No with. + reactions: 0.0. Total no. in groups: 12.0.

Key result

Reading:

other: first challenge

Group:

positive control

Dose level:

not reported

No. with + reactions:

3

Total no. in group:

10

Clinical observations:

erythema

Remarks on result:

positive indication of skin sensitisation

Remarks:

α- Hexylcinnamaldehyde was used as a positive control

Key result

Reading:

other: first challenge

Group:

positive control

Dose level:

not reported

No. with + reactions:

1

Total no. in group:

10

Clinical observations:

edema

Remarks on result:

positive indication of skin sensitisation

Remarks:

α- Hexylcinnamaldehyde was used as a positive control

Interpretation of results:

GHS criteria not met

Conclusions:

N6-Trifluoroacetyl-L-IysyI-L-proline has no sensitizing properties on the skin of guinea pigs in a study conducted according to OECD guideline 406 (1996). Thus, the test item does not need to be classified according to Regulation (EC) No 1272/2008 (CLP) and the Globally Harmonized System for Classification and Labelling of Chemicals (GHS).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

N6-Trifluoroacetyl-L-IysyI-L-proline has no sensitizing properties on the skin of guinea pigs in a study conducted according to OECD TG 406. Thus, the test item does not need to be classified according to Regulation (EC) No 1272/2008 (CLP) and the Globally Harmonized System for Classification and Labelling of Chemicals (GHS).