Arsenic acid

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

From February 29 to April 12, 1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP study conducted similarly to OECD Guideline 406 with deviations: less no. of animals used in treatment group; concentrations applied in induction phase caused mortalities and strong dermal reactions. Interpretaion of the results may have been false.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

yes

Remarks:

less no. of animals used in treatment group; concentrations applied in induction phase caused mortalities and strong dermal reactions

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPP 81-6 (Skin Sensitisation)

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes

Type of study:

Buehler test

Test material

Test material information

Constituent 1

Reference substance name:

Arsenic acid

EC Number:

231-901-9

EC Name:

Arsenic acid

Cas Number:

7778-39-4

Molecular formula:

H3AsO4

IUPAC Name:

arsoric acid

Details on test material:

- Name of test material (as cited in study report): Arsenic acid
- Physical state: Light green liquid
- Analytical purity: 75%
- Lot/batch No.: 8619
- Storage condition of test material: Room temperature

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

male

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

epicutaneous, occlusive

Vehicle:

water

Induction 2

Concentration / amount:

Range finding test: Topical induction exposure
- Experiment 1: 25, 50, 75 or 100% w/v
- Experiment 2: 0.1, 1, 10 and 25% w/v

Main test:
- Topical induction exposure: 25% w/v (first two doses) and 10% w/v (last dose)
- Topical challenge exposure: 1% w/v

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

water

Challenge 2

Concentration / amount:

Range finding test: Topical induction exposure
- Experiment 1: 25, 50, 75 or 100% w/v
- Experiment 2: 0.1, 1, 10 and 25% w/v

Main test:
- Topical induction exposure: 25% w/v (first two doses) and 10% w/v (last dose)
- Topical challenge exposure: 1% w/v

No. of animals per dose:

- Range finding test: 4 males
- Main test: 10 males (test and untreated control group), 4 males (positive control group)

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

25 or 10% w/v in deionised water

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

2/10 animals died within 10 days; surviving animals appeared normal at study termination

Remarks on result:

other: see Remark

Remarks:

Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 25 or 10% w/v in deionised water . No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: 2/10 animals died within 10 days; surviving animals appeared normal at study termination.

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

25 or 10% w/v in deionised water

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

2/10 animals died within 10 days; surviving animals appeared normal at study termination

Remarks on result:

other: see Remark

Remarks:

Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 25 or 10% w/v in deionised water. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: 2/10 animals died within 10 days; surviving animals appeared normal at study termination.

Any other information on results incl. tables

- 2/10 animals died within 10 days; surviving animals appeared normal at study termination

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

Under these test conditions, arsenic acid is not classified according to the Annex VI of the Directive 67/548/EEC and the CLP Regulation (EC) No. 1272/2008.

Executive summary:

In a Buehler closed patch study conducted similarly to OECD Guideline 406 and in compliance with GLP, a group of 10 male Dunkin-Hartley guinea pigs were topically induced with arsenic acid (0.4 mL) at a concentration of 25% w/v (first two doses) or 10% w/v in deionised water (last dose) via occlusive patch for 6 hours, followed by a rest period of 2 weeks and then with a challenge patch of 1% w/v. Ten naive animals were applied with a challenge patch in the same manner. Four animals in the positive control group were applied with three induction patches of 0.3% w/v 2,4-dinitrochlorobenzene (DNCB) in 80% ethanol/deionised water followed by a challenge patch of 0.1% w/v DNCB in acetone. The test concentrations for the main study were determined from the range-finding studies conducted at concentrations of 25, 50, 75 and 100% w/v (study 1) and 0.1, 1, 10 and 25% w/v in deionised water (study 2).

 

Topical induction indicated evidence of mild to strong dermal reactions. No skin reactions were noted at the challenge sites of the test or untreated control group animals at the 24 or 48-hour observations. Arsenic acid produced a 0% (0/20) sensitisation rate and was considered to be a nonsensitiser to guinea pig skin. Positive control exhibited evidence of sensitisation, thus confirming the susceptibility of this group of animals to dermal sensitisation.

 

Under these test conditions, arsenic acid is not classified according to the Annex VI of the Directive 67/548/EEC and the CLP Regulation (EC) No. 1272/2008. However this study is not considered as acceptable as it does not satisfy the guideline requirement for a skin sensitisation study.