L-Tyrosine, 3,5-dinitro-

Endpoint summary

Description of key information

Due to the physical chemical properties in vitro studies were not applicable for this substance.

An in vivo study on skin sensitisation potential according to OECD 429 (LLNA test) was conducted. The test substance was found to be non sensitizing.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Reference 1

Endpoint:

skin sensitisation: in vitro

Data waiving:

other justification

Justification for data waiving:

an in vitro skin sensitisation study does not need to be conducted because the available in vitro test methods are not applicable for the substance and therefore an in vivo skin sensitisation study was conducted

Reference 2

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

For in vitro tests, the test item is insoluble in all solvent indicated by the respective OECD guidelines at the required concentrations. Under these circumstances, in vitro skin sensitization testing in accordance with OECD 442C, OECD 442D and OECD 422E of L-Tyrosine, 3,5-dinitro- (wet product) was not possible. Other validated in vitro tests on skin sensitization are not available at present.

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

Strain:

CBA/Ca

Sex:

female

Details on test animals and environmental conditions:

The animals were housed in IVC polycarbonate cages (5 animals per cage) suspended on stainless steel racks, in a room equipped with central air-conditioning. The room temperature was within the range of 22 ± 3°C, relative humidity was within the range of 50 - 60 %. The light regimen was set to a 12-hour light / 12-hour dark cycle. The sanitation was performed according to standard operation procedures.

Vehicle:

acetone/olive oil (4:1 v/v)

Concentration:

Five female mice (CBA/Ca) per group were topically exposed (dorsum of both ears) to the test item at concentrations of 25%, 50% and 100%, to the positive control and to the vehicle only.

No. of animals per dose:

5 per dose, 5 per positive control, 5 per negative control (vehicle)

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Key result

Parameter:

SI

Value:

0.8

Test group / Remarks:

group 1: concentration 25%

Key result

Parameter:

SI

Value:

0.89

Test group / Remarks:

group 2: concentration 50%

Key result

Parameter:

SI

Value:

0.76

Test group / Remarks:

group 3: concentration 100%

The EC3 value could not be calculated, since none of the tested concentrations induced a S.I. was not greater than the threshold value of 3.

Interpretation of results:

GHS criteria not met

Conclusions:

The skin sensitizing potential of L-Tyrosine, 3,5-dinitro- (wet product) was assessed using the murine local lymph node assay.
Based on the results of this study, L-Tyrosine, 3,5-dinitro- (wet product) is not considered a skin sensitizer under the condition of this LLNA study.

Executive summary:

The skin sensitization potential of L-Tyrosine, 3,5-dinitro- (wet product) was evaluated by LLNA method,  which  basic  underlying  principle  is  that  sensitizers  induce  a  primary  proliferation  of lymphocytes in the auricular lymph nodes draining the site of chemical application.

In the present study, the test item was applied to the dorsum of each ear of five female mice (CBA/Ca) per group over three consecutive days, at three concentrations. All animals survived throughout the test period  without  showing  any  clinical  signs  of  toxicity. Calculated  SI  values  in  treated  groups remained  under  the  value  of  3,  which  is  the  threshold  to  consider  the  substance  as  a  sensitizer.

Therefore, it was not possible to calculate an EC3 value.

These results demonstrate that the test item  L-Tyrosine, 3,5-dinitro- (wet product) was not a skin sensitizer under the test conditions of this study.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available