Zinc cyanide

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

not specified

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

Guinea pig has been applied widely in sensitisation tests as a suitable experimental animal. In addition, sufficient raw data has been accumulated and it
is available for interpretation and evaluation of study results

Test material

Test material information

Constituent 1

Reference substance name:

Zinc cyanide

EC Number:

209-162-9

EC Name:

Zinc cyanide

Cas Number:

557-21-1

Molecular formula:

Zn(CN)2

IUPAC Name:

ZINC DICYANIDE

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

STORAGE AND TEMPERATURE: During the study, the test substances were kept in Storage Room 108-2. After the study, the rest of test substances were moved to the Storage Room 108-3. There was no need to record storage condition of the test solution because it was prepared in the morning of the administration day.

FORMULATION OF TEST SOLUTION: The test solution was prepared on the assumption that the purity was 100 %. On the administration day, the test substance was measured according to each defined concentration and dispersed evenly in the vehicle(corn-oil). The test
solution was prepared every morning of the administration day.

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

female

Details on test animals and environmental conditions:

Number : 38 female animals
Age: 6 weeks old
Body weight at the acquisition: 284.43 ～ 309.19 g
Quarantine and acclimatation: Animal physical condition and record of health monitoring were checked at the day of animal receipt. Animals were acclimated for 12 days. Only animals with the best appearance were selected for the test animals after observation during the acclimation perid.
Body weights at the administration: 335.57 ~ 380.03g
Number of used animals for the pilot test: 6 animals
Number of used animals for the main test: 30 animals

ENVIRONMENTAL CONDITIONS:
- Temperature and humidity: : 21.4±0.3 ℃ and 48.2±3.4 % Relative Humidity
- Ventilation frequency: 10-15 air changes/hour
- Lighting cycle: : 12 hours duration (lighting on at 8 a.m. and off at 8 p.m.
- Lighting intensity: 297 Lux
- Noise: 51.8 dB
All animals were housed in a plastic cage (810 W × 610 L × 260 H ㎜) during acclimation, administration and observation period. During the experiment, not more than 5 animals were housed in each cage.
Laboratory animal feed (Guinea pig Diet, Cargill Agri Purina Inc, Korea) was supplied to the animals ad libitum in stainless feeder. Incheon, Korea municipal tap water purified by reverse osmosis filtering system was provided ad libitum using plastic bottles. The feed and water analysis were carried out in accordance with SOPs (Standard Operating Procedure) of our test facility.

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal

Vehicle:

corn oil

Concentration / amount:

0.1ml

Day(s)/duration:

1 injection

Adequacy of induction:

not specified

Induction 2

Route:

other: epicutaneous

Vehicle:

water

Concentration / amount:

0.2ml

Day(s)/duration:

48h

Adequacy of induction:

not specified

Challenge

Route:

other: epicutaneous

Vehicle:

corn oil

Concentration / amount:

0.1ml

Day(s)/duration:

24h

Adequacy of challenge:

not specified

Challenge controls:

Challenge exposure was performed in all animals. Both sides of the flank were cleared of hair in all animals. The test substance and vehicle 0.1 ㎖ were fully loaded in each patch (WhatmanTM filter paper, 2 × 2 ㎝). The test substance was applied to left flank of the animal and vehicle was applied to right flank using a non-irritant adhesive vinyl (TegadermTM 1624W, 3M). And then, all tested animals were wrapped in a bandage(MicroporeTM 1530-1, 3M) to the skin for 24 hour.

Results and discussion

In vivo (non-LLNA)

Results

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

0.1ml

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

The skin reaction (edema or erythema) was not observed at 24, 48 hours after removal of challenge patch.

Remarks on result:

no indication of skin sensitisation

Any other information on results incl. tables

There was no clinical signs and mortalities related to the application of test substance during this study. There was no significant body weight changes related to the application of test substance during this study. In the case of vehicle control group, the skin reaction (edema or erythema) was not observed at 24, 48 hours after removal of challenge patch. Therefore, the final sensitisation rate of vehicle control group was 0 % and vehicle control was classified with “Weak”(Grade I) sensitizer. In the case of test substance treated group, the skin reaction (edema or erythema) was not observed at 24, 48 hours after removal of challenge patch. Therefore, the final sensitisation rate of test substance treated group was 0 % and the test substance was classified with “Weak”(Grade I) sensitizer.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the results described above, the sensitisation rate of Zinc cyanide was considered as 0 % and Zinc cyanide was classified with “Weak”(Grade I) sensitizer according to “criteria for skin sensitisation” in female Hartley Guinea Pigs.

Executive summary:

For that endpoint, one reliable study to assess skin sensitisation in vivo on the registered substance on female guinea pig was available. The study was performed according to the OECD Guideline 406 (Skin Sensitisation).

Under the experimental conditions, the sensitisation rate of Zinc cyanide batch n°10185145 was considered as 0 % and Zinc cyanide batch n°10185145 was classified with “Weak”(Grade I) sensitizer according to “criteria for skin sensitisation” in female Hartley Guinea Pigthe.

The validity criteria were successful and the study was therefore regarded as acceptable for that endpoint.