Ammonium iodide

Endpoint summary

Description of key information

The target chemical was considered to be not sensitizing to skin and it can be further classified under the category “Not Classified” as per CLP regulation. 

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

Experimental data from various test chemicals

Justification for type of information:

Data for the target chemical is summarized based on data from various test chemicals

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

WoE for the target chemical is summarized based on data from various test chemicals

GLP compliance:

not specified

Type of study:

other:

Specific details on test material used for the study:

- Name of test material: Ammonium iodide
- IUPAC name: Ammonium iodide
- Molecular formula: H4IN
- Molecular weight: 144.939 g/mole
- Smiles Notation : [NH4+].[IH-]
- InChl: 1S/HI.H3N/h1H;1H3
- Substance type: Inorganic
- Physical state: Solid crystalline powder (colorless to white)

Species:

other: 1. humans 2. guinea pigs

Strain:

other: 3. Pirbright-Hartley

Sex:

not specified

Details on test animals and environmental conditions:

2. No data
3. TEST ANIMALS
- Age at study initiation: 8 weeks age
- Weight at study initiation: 240

Route:

epicutaneous, open

Vehicle:

petrolatum

Concentration / amount:

Ranging from 5 to 20 %

Adequacy of induction:

not specified

Route:

intradermal and epicutaneous

Vehicle:

other: 0.9% NaCl solution

Concentration / amount:

1st: Induction 5 %, intracutaneous
2nd: Induction 25 % , occlusive epicutaneous

Day(s)/duration:

Single

Adequacy of induction:

not specified

No.:

#1

Route:

epicutaneous, open

Vehicle:

petrolatum

Adequacy of challenge:

not specified

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

other: 0.9% NaCl

Concentration / amount:

Challenge 10 %, occlusive epicutaneous

Adequacy of challenge:

not specified

No. of animals per dose:

2. 8 patients
3. 20 guinea pigs

Details on study design:

2. No data

3. RANGE FINDING TESTS: no data available

MAIN STUDY
A. INDUCTION EXPOSURE
Intracutenous exposure
- No. of exposures: single
- Exposure period: 24 hours
- Test groups: 20
- Control group:
- Site: no data
- Frequency of applications: single
- Duration: - Concentrations: 5 %.

Epicutaneous, Occlusive

- No. of exposures: single
- Exposure period: 48 hours
- Test groups: 20
- Control group: no data available
- Site: no data availalbe
- Frequency of applications: single
- Duration: 48 hours
- Concentrations: 0.5 ml of 25 %

B. CHALLENGE EXPOSURE
- No. of exposures: single
- Day(s) of challenge: day 22
- Exposure period: 24 hours
- Test groups: 20
- Control group: no data available
- Site: clipped skin of the flank
- Concentrations: 0.5 ml of 10 %
- Evaluation (hr after challenge): 24 and 48 hours after removal of the occlusive dressing

OTHER:
Day 1 : Intradermal induction exposure (Injection)
The injection sites were not covered.
Day 1-7: The application area was investigated.
Day 9 : Dermal induction exposure0.5ml of the test substance preparation was applied to a cellulose patch of 2x4 cm. This patch cover ed the area of the intradermal injection sites. An occlusive dressing with impermeable foil and an elastic bandage sealed the application site for 48 hours.
Day 11 : Removal of the occlusive dressing. Recording of the irritation
Day 22 : Dermal challenge exposure0.5ml of test substance preparation were applied to a cellulose patch and placed onto the clipped skin of the flank. An occlusive dressing with impermeable foil and an elastic bandage sealed the application site for 24 hours.
Day 23 : Removal of the occlusive dressing
Day 24-25: Assessment of the skin

Challenge controls:

no data available

Positive control substance(s):

not specified

Positive control results:

no data available

Reading:

1st reading

Group:

test chemical

Dose level:

Concentrations ranging from 5 to 20 per cent in petrolatum

No. with + reactions:

3

Total no. in group:

8

Clinical observations:

no reactions observed

Remarks on result:

no indication of skin sensitisation

Remarks:

2

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

10%

No. with + reactions:

2

Total no. in group:

20

Clinical observations:

The treated animals did not show any signs of toxicity throughout the study period

Remarks on result:

no indication of skin sensitisation

Remarks:

3

Interpretation of results:

other: not sensitizing

Conclusions:

On the basis of available studies for the various test chemicals, the weight of evidence approach was applied to assess the skin sensitization potential for target substance. The test chemicals was considered to be not sensitizing to skin.

Executive summary:

Data available for the various test chemicals was reviewed to determine the toxic nature of the test chemical. The studies are as mentioned below:

 

Patch tests were conducted to determine the dermal sensitization potential of the test chemical in humans. 8 patients were tested with the test chemical in concentrations ranging from 5 to 20 per cent in petrolatum, and observed for signs of irritation. (duration not specified). In five of eight patients tested with the test chemical, the reactions were negative for skin sensitisation. Hence the test chemical was considered to be not sensitizing to skin.

 

The above result is supported by A Guinea pig Maximization assay performed to determine the dermal sensitization potential of the test chemical. The study was performed as per EPA 540/9-82-025 Guidelines. 20 female Pirbright White guinea pigs were used for the study. 0.9% NaCl Solution was used as a vehicle. The following concentrations were used for the induction and challenge exposure-

1st: Induction 5 %, intracutaneous

2nd: Induction 25 % , occlusive epicutaneous

3rd: Challenge 10 %, occlusive epicutaneous

During the first phase of induction, intracutaneous injections were given to the test animals and injection sites were investigated till day 7. In day 9,0.5ml of the test substance preparation was applied to a cellulose patch of 2x4 cm. This patch covered the area of the intradermal injection sites. An occlusive dressing with impermeable foil and an elastic bandage sealed the application site for 48 hours. At the end of 48 hours of exposure, the occlusive bandages were removed and the test sites were observed for signs of erythema and edema. The animals were rested for 10-11 days then subjected to challenge exposure. 0.5ml of test substance preparation were applied to a cellulose patch and placed onto the clipped skin of the flank. An occlusive dressing with impermeable foil and an elastic bandage sealed the application site for 24 hours. 24 hours later the occlusive patches were removed and the test sites were assessed for dermal irritation. The treated animals did not show any signs of toxicity throughout the study period. Very slight to slight edema were observed in the treatment group. 24 and 48 hours after removal of the occlusive dressing, a total of 2 animals (in 20) of the treatment group showed very slight, hardly perceptible erythema. Ten percent of the animals of treatment group demonstrated a positive reaction after the challenge exposure (classification criteria – 30%). Hence, the test chemical was considered to be not sensitizing to skin.

Based on the available data for the various test chemicals and applying the weight of evidence approach, it can be concluded that the target chemical will also tend to behave in a similar manner as that of the test chemicals. Therefore the target chemical was considered to be not sensitizing to skin and it can be further classified under the category “Not Classified” as per CLP regulation. 

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Data available for the various test chemicals was reviewed to determine the toxic nature of the test chemical. The studies are as mentioned below:

 

Patch tests were conducted to determine the dermal sensitization potential of the test chemical in humans. 8 patients were tested with the test chemical in concentrations ranging from 5 to 20 per cent in petrolatum, and observed for signs of irritation. (duration not specified). In five of eight patients tested with the test chemical, the reactions were negative for skin sensitisation. Hence the test chemical was considered to be not sensitizing to skin.

 

The above result is supported by A Guinea pig Maximization assay performed to determine the dermal sensitization potential of the test chemical. The study was performed as per EPA 540/9-82-025 Guidelines. 20 female Pirbright White guinea pigs were used for the study. 0.9% NaCl Solution was used as a vehicle. The following concentrations were used for the induction and challenge exposure-

1st: Induction 5 %, intracutaneous

2nd: Induction 25 % , occlusive epicutaneous

3rd: Challenge 10 %, occlusive epicutaneous

During the first phase of induction, intracutaneous injections were given to the test animals and injection sites were investigated till day 7. In day 9,0.5ml of the test substance preparation was applied to a cellulose patch of 2x4 cm. This patch covered the area of the intradermal injection sites. An occlusive dressing with impermeable foil and an elastic bandage sealed the application site for 48 hours. At the end of 48 hours of exposure, the occlusive bandages were removed and the test sites were observed for signs of erythema and edema. The animals were rested for 10-11 days then subjected to challenge exposure. 0.5ml of test substance preparation were applied to a cellulose patch and placed onto the clipped skin of the flank. An occlusive dressing with impermeable foil and an elastic bandage sealed the application site for 24 hours. 24 hours later the occlusive patches were removed and the test sites were assessed for dermal irritation. The treated animals did not show any signs of toxicity throughout the study period. Very slight to slight edema were observed in the treatment group. 24 and 48 hours after removal of the occlusive dressing, a total of 2 animals (in 20) of the treatment group showed very slight, hardly perceptible erythema. Ten percent of the animals of treatment group demonstrated a positive reaction after the challenge exposure (classification criteria – 30%). Hence, the test chemical was considered to be not sensitizing to skin.

Based on the available data for the various test chemicals and applying the weight of evidence approach, it can be concluded that the target chemical will also tend to behave in a similar manner as that of the test chemicals. Therefore the target chemical was considered to be not sensitizing to skin and it can be further classified under the category “Not Classified” as per CLP regulation. 

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The results of the experimental studies from the similar read across substances indicate a possibility that Ammonium Iodide can be not sensitizing to skin.

Hence by applying the weight of evidence approach, Ammonium Iodide can be considered to be not sensitizing to skin. It can be classified under the category “Not Classified” as per CLP regulation.