Nadide

Endpoint summary

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:

weight of evidence

Study period:

2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

In vivo study that was performed before 10 May 2017

Species:

guinea pig

Strain:

other: Crl:HA - Guinea Pigs

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River, 97633 Sulzfeld, Germany
- Age at study initiation: approximately 4 weeks
- Weight at study initiation: 353- 399 g
- Housing: Semi barrier in an air-conditioned room
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum):ad libitum
- Acclimation period: at least five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3 oc
- Humidity (%): 55+/- 10%
- Air changes (per hr): at least I 0 x I hour
- Photoperiod (hrs dark / hrs light) :Artificial light, sequence being 12 hours light, 12 hours dark

Route:

intradermal and epicutaneous

Vehicle:

other: vaseline

Concentration / amount:

2.5% and 50%

Route:

epicutaneous, occlusive

Vehicle:

other: vaseline

Concentration / amount:

2.5% and 50%

No. of animals per dose:

Number of animals in the test group: 10
Number of animals in the negative-control group: 5
Number of animals in the dose range finding study: 3

Details on study design:

RANGE FINDING TESTS:
For the justification of dose levels a preliminary test was performed.
1 animal was treated intradermally with concentrations of 5% and 2.5% of the test item (dissolved in physiological saline 0.9% NaCl)
1 animal was treated topically with concentrations of 50% and 25% of the test item (suspended in vaseline), for 24 hours.
1 animal was treated topically with concentrations of 50% and 25% of the test item (suspended in vaseline), for 48 hours.
MAIN STUDY
A. INDUCTION EXPOSURE
induction: First Stage, lntradermal lnjection
Three pairs of intradermal injections of 0.1 mL volume were given in the shoulder region which was cleared of hair by clipping so that one of each par lies on each side of the midline.
Test Group: Day 0
Injection I: a I: I mixture (v/v) FCA/physiological saline 0.9% NaCl
Injection 2: 2.5% the test item in physiological saline 0.9% NaCl
Injection 3: 2.5% the test item formulated in a I :I mixture (v/v) FCA/physiological
saline 0.9% NaCl
Control Group: Day 0
Injection I: a I: I mixture (v/v) FCA/physiological saline 0.9% NaCI
Injection 2: 100% physiological saline 0.9% NaCl
Injection 3: a 50% (v/v) formulation of physiological saline 0.9% NaCl in a 1:1 (v/v)
mixture FCA/physiological saline 0.9% NaCl
Injections I and 2 were given close to each other and nearest to the head, while
injection 3 was given toward the caudal part of the test area.
11. 7. Induction: Second Stage, Topical Application
Test Group and Control Group: Day 6
Approximately twenty-four hours before the topical application the test area was
painted with 0.5 g of I 0% sodium Iaury! sulphate in vase line after close clipping in
order to create a local irritation.
Test Group: Day 7
The test item was suspended in vaseline at a concentration of 50%. A patch was fully
loaded with 0.5 g of the prepared test item. Then it was applied to the test area and held
in contact with the help of an occlusive dressing for 48 hours.
Control Group: Day 7
A patch was fully loaded with 0.5 g ofvaseline. Then it was applied to the test area and
held in contact with the help of an occlusive dressing for 48 hours.

B. CHALLENGE EXPOSURE
Challenge: Topical Application
The flanks of treated and control animals were cleared of hair by close-clipping.
Test Group and Control Group: Day 20
The test item was suspended in vaseline at a concentration of 50%. A patch, loaded with
0.5 g of the prepared test item was applied to the left flank of the animals and a patch
loaded with 0.5 g of the vehicle to the right flank (intraspecific control). The patches
were held in contact with the help of an occlusive dressing for 24 hours.
The application area was not rinsed.
OTHER:

Positive control substance(s):

yes

Remarks:

mercaptobenzothiazole, purity> 98%

Positive control results:

The sensitisation rate after application of the positive-control substance mercaptobenzothiazole (15% in vaseline) was IOO%, confirming the reliability of the test system.

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

50%

No. with + reactions:

0

Total no. in group:

10

Reading:

rechallenge

Hours after challenge:

48

Group:

test chemical

Dose level:

50%

No. with + reactions:

0

Total no. in group:

10

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

50%

No. with + reactions:

0

Total no. in group:

5

Remarks on result:

no indication of skin sensitisation

Reading:

2nd reading

Hours after challenge:

48

Group:

positive control

Dose level:

15%

No. with + reactions:

5

Total no. in group:

5

Challenge Concentrations of Test Substance: 50%

Number of animals showing skin reaction after:    24 hours  48 hours  Test group  0 0   Negative-control group 0  0

Interpretation of results:

not sensitising

Conclusions:

Under the conditions of the present study it can be stated that the test item b-Nicotinamide-adenine Dinucleotide II (nadide) caused no reactions
identified as sensitisation at the tested concentration. According to the EC criteria for classification and labelling requirements for dangerous
substances and preparations labelling is not necessary.

Executive summary:

Skin sensitisation potential of Nadide was tested using the Guinea Pig Maximisation Test in accordance with OECD guideline 406.

A preliminary test was used to determine the concentrations to be used. The concentrations chosen for the main test were: 2.5% for the intradermal induction; 50% for the dermal induction and 50% for the challenge concentration. 10 female guinea pigs (Crl:HA) were used as test group and 5 animals in the negative control group. Under the conditions of the present study it can be stated that the test item b-Nicotinamide-adenine Dinucleotide II (nadide) caused no reactions

identified as sensitisation at the tested concentration. According to the EC criteria for classification and labelling requirements for dangerous substances and preparations labelling is not necessary. The substance is also considered unclassified according to GHS.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

B-NICOTINAMIDE-ADENINE DINUCLEOTIDE II (NADIDE) has been studied for its potential to induce skin sensitization in the murine local lymph node assay (LLNA) and in the Maximization assay in the guinea pig. Results obtained in the LLNA test (NOTOX No. 496791) suggested the compound could stimulate lymphocytic proliferation in the regional lymph nodes of the mice. The effect was significant, i.e. reached the cut – off value of 3 in the assay at the highest applied test article concentration of 50% only. At this concentration the compound induced significant inflammation, i.e. proved irritating to the ear. The irritant effect was particularly evident through evaluating the skin reaction erythema and measuring the ear thickness during the pre-test of the study. Although, such a response was not reported in the main part of the study, it is likely that the compound possessed irritating potential at the highest tested concentration of 50%. Since the LLNA is known to be liable, i.e. produce false positive results due to non-specific irritating influences of a test article the confirmatory guinea pig sensitization assay, the Maximization-test (Roche Report 1039127) has been carried out as a follow-up study of skin sensitization. None of the test or control animals showed any skin response or sign of sensitization at the topical administration of the - in this assay non-irritating - highest concentration of 50% of the test article. In summary: the lymphoproliferative response detected in the LLNA is likely due to non-specific irritating effects of the test substance in the mice. Since the compound proved clearly negative in the more specific Maximization – test in the guinea pig the test article B-NICOTINAMIDE-ADENINE DINUCLEOTIDE II (NADIDE) is not considered to be a skin sensitizer. Accordingly, no respective labeling or classification of the compound is required.

Justification for selection of skin sensitisation endpoint:
the LLNA test was not reliable as it produced false positive result which produced non-specific irritating influences of nadide at the 50% concentration used.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Since the LLNA is known to be liable, i.e. produce false positive results due to non-specific irritating influences of a test article the confirmatory guinea pig sensitization assay, the Maximization-test (Roche Report 1039127) has been carried out as a follow-up study of skin sensitization. None of the test or control animals showed any skin response or sign of sensitization at the topical administration of the - in this assay non-irritating - highest concentration of 50% of the test article. In summary: the lymphoproliferative response detected in the LLNA is likely due to non-specific irritating effects of the test substance in the mice. Since the compound proved clearly negative in the more specific Maximization – test in the guinea pig the test article B-NICOTINAMIDE-ADENINE DINUCLEOTIDE II (NADIDE) is not considered to be a skin sensitizer. Accordingly, no respective labeling or classification of the compound is required.