Hydroxido potassium zirconium carbonate, where there are 0, 1 or 2 hydroxide groups and 2, 3 or 4 potassium atoms and 2, 3 or 4 carbonate groups.

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

9 December 1992 - 8 January 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: A GLP study performed to standardised guidelines with a sufficient level of detail to assess the quality of the submitted data.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1993

Report date:

1993

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Test material

Test material information

Constituent 1

Reference substance name:

Potassium Zirconium Carbonate

IUPAC Name:

Potassium Zirconium Carbonate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

Fifty two young adult (less than one year old), nulliparous and non-pregnant, female albino guinea pigs of the Dunkin-Hartley strain, within the weight range 338-486 g at main test commencement, were used. They were supplied by David Hall Limited, Darley Oaks, Newchurch, Burton-on-Trent, Staffordshire, and arrived at Elphinstone Research Centre on 1 December 1992.
Twenty test group and 20 control group guinea pigs were housed 5 to a cage. Twelve dose ranging guinea pigs were housed 4 to a cage in 3 further cages. Each aluminium cage had a grid floor beneath which was an absorbent paper lined tray.
The animals were fed FD1 Guinea Pig Diet, supplied by Special Diets Services Limited, 1 Stepfield, Witham, Essex, CM8 3AD, supplemented with hay and allowed food and tap water ad libitum. The diet and water are analysed on a regular basis and meet the criteria laid down by IRI.
Mean environmental maximum and minimum temperatures were 20°C and 19°C and mean relative humidity was 49%. A 12 h light/dark cycle was in operation (light hours 0700-1900 h).
The guinea pigs were allowed an acclimatisation period of at least 8 days prior to test commencement.
The guinea pigs were identified by means of indelible ear marks and colour code using a system routinely used at IRI. Main study animals were weighed at test commencement and completion.

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

water

Induction 2

Concentration / amount:

Induction: 2% (injection) and 75% (topical) w/v in distilled water
Challenge: 75% w/v in distilled water

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

water

Challenge 2

Concentration / amount:

Induction: 2% (injection) and 75% (topical) w/v in distilled water
Challenge: 75% w/v in distilled water

No. of animals per dose:

20 test animals, 20 control animals

Details on study design:

The Magnusson-Kligman Maximisation Test comprises 2 procedures; an induction procedure and a challenge procedure (Magnusson B, Kligman A M (1969), J Invest Dermat, 52, 268-276).
The induction procedure consists of an intradermal injection of the test material, followed after one week by a topical application. The challenge procedure, which consists of a topical application, is carried out 3 weeks after commencement of the induction procedure.

The test was carried out using the following method:

i) Induction

Dose Ranging Test for Induction
A preliminary dose ranging test was carried out to assess suitable concentrations for injection and topical application on 8 previously untreated guinea pigs. Injections were in the shaved scapular region and topical application was on the shaved flanks. Four guinea pigs were subjected to intradermal injections and a further 4 guinea pigs were exposed to topical application of the test material for 48 h. Eight concentrations were investigated.

Injections - 75%, 50%, 25%, 15%, 10%, 5%, 2% and 1% w/v in distilled water
Topical application - 75%, 50%, 25%, 15%, 10%, 5%, 2% and 1% w/v in distilled water

The injection sites were assessed for irritation 24, 48 and 72 h after injection, and the topical application sites were assessed for irritation 24 and 48 h after patch removal. Assessments were made using Scale A described below.

Main Test - Injection Phase
In the main test, hair was shaved from an area 4 cm x 6 cm across the scapular region of 44 guinea pigs. These animals were allocated as follows:

Test group: 20 guinea pigs
Control group: 20 guinea pigs
Challenge dose ranging group: 4 guinea pigs

The test group guinea pigs were each given 6 intradermal injections, 3 in a line each side of and parallel to the mid-line in the shaved region as follows:
0.10 ml Freund's Complete Adjuvant (anterior injection)
0.10 ml test material (middle injection)
0.10 ml of a 50:50 emulsion of test material in Freund's Complete Adjuvant (posterior injection)
The test material was injected at a concentration of 2% w/v in distilled water. The concentration of test material in Freund's Complete Adjuvant was also 2%.
The 20 control group guinea pigs were similarly treated, but with the vehicle, distilled water, replacing the test material.
Approximately 1 h and 24 h after injection, the treated sites of both test and control groups were assessed for irritation using Scale A described below.
The 4 guinea pigs intended for dose ranging for challenge were each given a 0.1 ml intradermal injection of Freund's Complete Adjuvant on either side of the mid-line of the shaved scapular region.

Main Test - Topical Application Phase
Six days after the injection phase, the injection site of each of the test and control group animals was shaved again and then wetted with 10% aqueous sodium lauryl sulphate (SLS) to provoke a mild inflammatory response to enhance the possibility of sensitisation.
After approximately 24 h, a 2 cm x 4 cm patch of Whatman chromatography paper, charged with the test material at a concentration of 75% w/v in distilled water, was applied to the pretreated area of each of the test group animals. The patch was covered by an overlapping piece of impermeable plastic adhesive tape (Blenderm). The whole area was then firmly bound with Sleek occlusive tape, and the dressing was left in place for 48 h before removal.
The control group guinea pigs were similarly treated, but with the vehicle, distilled water, replacing the test material.
One hour and 24 h after patch removal, the treated sites of both test and control groups were assessed for irritation using Scale A described below.
The 4 guinea pigs intended for dose ranging for challenge were untreated at this stage.

Assessment of Response at Induction

Scale A

No visible change: 0
Slight reaction: 1
Moderate reaction: 2
Severe reaction and/or necrosis: 3

ii) Challenge

Dose Ranging Test for Challenge
Before challenging the test animals, a maximum non-irritant concentration of the test material was determined in a preliminary experiment on 4 dose ranging guinea pigs. The animals were pretreated at the induction phase with Freund's Complete Adjuvant only.
The test material was applied to the shaved flanks of the guinea pigs for 24 h at concentrations of 75%, 50%, 25% and 15% w/v in distilled water using the same method as topical induction. Reactions were assessed 24 h later using Scale B described below.

Main Test - Challenge Phase
Two weeks after the start of topical induction, both the test and control group guinea pigs were challenged with the test material at a concentration of 75% w/v in distilled water, and with the vehicle, distilled water. A 5 cm x 5 cm area of the left flank was shaved and the test and control materials were applied to the prepared test site on 2 cm x 2 cm pieces of filter paper. The patches were held in place for 24 h using the same method as topical induction, after which time they were removed.
The degree of response was determined by trained assessors 24 and 48 h after removal of the challenge patch when an allergic response would be at a peak. Animals were shaved approximately 3 h prior to the 24 h assessment. Any animal showing erythema at the site of challenge was considered to have shown a positive response.

Assessment of Response at Challenge

Scale B

No visible change: 0
Slight or discrete erythema: 1
Moderate and confluent erythema: 2
Intense erythema and/or oedema: 3

The sensitisation potential of the test material is rated according to the percentage of animals sensitised, based on Magnusson-Kligman as follows:
Sensitisation Grade Classification
0-8% I Weak
9-28% II Mild
29-64% III Moderate
65-80% IV Strong
81-100% V Extreme

Positive control substance(s):

yes

Remarks:

2,4-dinitro-chlorobenzene (DNCB)

Results and discussion

Positive control results:

The sensitivity of this strain of guinea pig to a known sensitiser, 2,4-dinitro-chlorobenzene (DNCB), is checked at 6 monthly intervals. The most recent positive control test with DNCB was completed on 14 September 1992 when 60% of the test group animals reacted positively.

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

75% w/v

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

None

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 75% w/v. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: None.

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

75% w/v

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

None

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 75% w/v. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: None.

Any other information on results incl. tables

Dose Ranging Test for Induction

Slight to moderate irritation was noted at sites injected with the test material at concentrations of 75%, 50%, 25%, 15%, 10% and 5% w/v in distilled water. Slight irritation was noted at a concentration of 2% w/v in distilled water and this was the concentration selected for the injection phase of induction in the test group, this being the highest practicable concentration.

No irritation was noted at sites treated topically with the test material. A concentration of 75% w/v in distilled water was selected for the topical application phase of induction in the test group.

Main Test - Induction

Slight to moderate irritation was noted in the test and control groups.

Dose Ranging Test for Challenge

No irritation was noted at sites treated topically with the test material at concentrations of 75%, 50%, 25% and 15% w/v in distilled water. A concentration of 75% w/v in distilled water was selected for challenge.

Main Test - Challenge

Following challenge with the test material at a concentration of 75% w/v in distilled water, none of the 20 test group animals showed positive reactions to this application. None of the 20 control group animals, which had previously only been exposed to the vehicle, distilled water, showed a positive reaction to this application.

There was no reaction in the test or control groups to challenge with the vehicle, distilled water.

Body Weight

Body weights were recorded at main test commencement and on test completion. Body weight gains were acceptable with the exception of one control group animal which showed a low weight gain.

Clinical Signs

No clinical signs, other than skin reactions induced by treatment, were noted.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test material was determined to be non-sensitising in a Guinea pig maximisation study. Animals were exposued to the test material at concentrations of 2% (injection) and 75% (topical) w/v in distilled water in the induction exposure and 75% w/v in the challenge. Under the conditions of the test a reaction to the challenge was not observed.

Executive summary:

The sensitisation potential of a test material was investigated by means of the Magnusson-Kligman Maximisation Test in guinea pigs.

Induction with the test material was at concentrations of 2% (injection) and 75% (topical) w/v in distilled water. Challenge was at a concentration of 75% w/v in distilled water.

At challenge, none of the test or control group animals treated with the test material at a concentration of 75% w/v in distilled water showed a positive response.

There is no evidence from the test results that the test material is a sensitiser in guinea pigs.