Pyrochlore, antimony lead yellow

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation, other

Remarks:

in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

August-December 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well-documented and corresponded to the requirements of the recommended Annex V Test Guidelines.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

yes

Remarks:

There was one deviation from the study protocol which was concerned with the relative humidity (section 6.2 Husbandry). At some days of the study the relative humidity was higher than 70%.

GLP compliance:

yes (incl. QA statement)

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

Appropriate guinea pig maximisation test available which would not justify conducting an additional LLNA due to animal welfare.

Test material

Test material information

Constituent 1

Reference substance name:

Trilead dioxide phosphonate

EC Number:

235-252-2

EC Name:

Trilead dioxide phosphonate

Cas Number:

12141-20-7

Molecular formula:

HO5PPb3

IUPAC Name:

trilead dioxide phosphonate

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

- Name of test material (as cited in study report): ALLSTAB LP 3139 dibasic lead phosphite
- Molecular formula (if other than submission substance): 2PbO x PbHPO3 x 0.5 H2O
- Physical state: fine white powder
- Analytical purity: 99.3%
- Lot/batch No.: 0210510067
- Expiration date of the lot/batch: > 24 months after shipping
- Storage condition of test material: At room temperature. Shelf Life: min. 24 months (sfter shipment), when stored in sealed containers at temperatures below 40 degrees centigrade.

In vivo test system

Test animals

Species:

guinea pig

Strain:

other: pirbright white

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland GmbH
- Age at study initiation:
- Weight at study initiation: males: 459-545 g; females: 416-530 g
- Housing: The guinea pigs were kept in collective housing up to a maximum of 5 animals per cage in a battery of cages, equipped with a paper disposal system.
- Diet (e.g. ad libitum): "2040 Teklad Global Guinea Pig Diet" (pelleted diet, batch no. K080) offered ad libitum.
- Water (e.g. ad libitum): Tap water as for human consumption was continuously available ad libitum via drinking nipples.
- Acclimation period: 19 days (range finding); 22 days (main test)


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3 degrees centigrade
- Humidity (%): 37-76%
- Air changes (per hr): 16 times/ hour and filtered adequately
- Photoperiod (hrs dark / hrs light): 12 hours dark/12 hours light with light on at 7:00AM


IN-LIFE DATES: From: To:

Study design: in vivo (non-LLNA)

Induction

Route:

intradermal and epicutaneous

Vehicle:

other: For the intradermal injection, the test article was diluted with aqua ad iniectabilia and Freund's complete adjuvant to a final concentration of 5%. For the dermal application, the solid test article was used as 50% formulation in petrolatum.

Concentration / amount:

Intradermal injection 5% of the test article
Dermal application 50% in petrolatum

Challenge

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

other: For the dermal application, the solid test article was used as 50% formulation in petrolatum.

Concentration / amount:

Dermal application 50% in petrolatum

No. of animals per dose:

10 test and 5 control animals

Details on study design:

RANGE FINDING TESTS: The range finding test was performed to determine the concentration of the test article to be used in the main test. For the intradermal injection, the test article was diluted with aqua ad iniectabilia (Delta-Pharma, Pfullingen) and Freund's complete adjuvant (FCA; batch no. 62K8933; SIGMA, Steinheim) to a final concentration of 5.0%. Two animals were employed, skin reactions being recorded 48 and 72 hours after treatment. For the dermal application, the solid test substance was used 50% in petrolatum. A closed patch exposure was effected by means of an occlusive bandage using cellulose swabs, Leukosilk and non-irritating tape Elastoplast, which enveloped the whole animal's trunk. Two animals were employed and skin reactions were recorded 48 and 72 hours post application.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 3 injection sites
- Exposure period: Seven days after injection, the injection sites were covered occlusively for 48 hours.
- Test groups: 10
- Control group: 5
- Site: Clipped intracapsular region on either side of the spine.
- Frequency of applications: Three pairs of intradermal injections (0.1 ml)
- Duration: Seven days later, the previous injection sites were covered occlusively for 48 hours with a patch carrying the test article (50%) or, in control animals, the control article petrolatum.
- Concentrations: Test Group: 1) FCA 50% (v/v) diluted in aqua ad iniectabilia, 2) testt article 5% in peanut oil, 3) test article 5% in aqua ad iniectabilia/FCA. Control Group: FCA 50% (v/v) diluted in aqua ad iniectabilia, 2) peanut oil, 3) peanut oil 50% (v/v) diluted in FCA.

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: Both control and test animals were subjected to a challenge exposure 14 days after the second stage of the induction.
- Exposure period: 24 hours
- Test groups: 10
- Control group: 5
- Site: 5 x 5 cm clipped skin area on each flank
- Concentrations: The test substance was applied at the concentration of 50% to the left flank and the control substance petrolatum to the right in a volume of 0.5 g using the patch technique described under 6.2.1. In each case, the duration of the exposure was 24 hours under an occlusive dressing.
- Evaluation (hr after challenge): 24 and 48 hours after challenge.

Challenge controls:

Both control and test animals were subjected to a challenge exposure 14 days after the second stage of the induction. The challenge test was performed on a 5 x 5 cm clipped skin area on each flank. The test substance was applied at the concentration of 50% to the left flank and the control substance petrolatum to the right in a volume of 0.5 g using the patch technique described under 6.2.1. In each case, the duration of the exposure was 24 hours under an occlusive dressing.

Positive control substance(s):

no

Remarks:

The sensitivity of the test system and the reliability of the experimental technique is assessed at least every 6 months by use of "4-aminobenzoic acid ethyl ester (benzocaine)" which is known to induce skin sensitisation in guinea pigs.

Study design: in vivo (LLNA)

Vehicle:

other: petrolatum

Concentration:

50 and 25 % in Vaseline (petrolatum)

No. of animals per dose:

10

Details on study design:

The sensitivity of the test system and the reliability of the experimental technique is assessed at least every 6 months by use of "4-aminobenzoic acid ethyl ester (benzocaine)" which is known to induce skin sensitisation in guinea pigs. This test was conducted as a Magnusson & Kligman test according to the OECD Guideline for the Testing of Chemicals, OECD 406, 17 July 1992 and to the EEC Directive 2001/59/EEC, 6 August 2001.

Results and discussion

Positive control results:

Sensitisation rate (50%) at 24 hours: 70% Sensitisation rate (50%) at 48 hours: 70%
Sensitisation rate (25%) at 24 hours: 30% Sensitisation rate (25%) at 48 hours: 20%

In vivo (non-LLNA)

Results

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

50% in petrolatum

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

0 %

Any other information on results incl. tables

There were no skin reactions after the dermal application in the induction phase. No allergic skin reactions were observed in test animals after the challenge exposure 24 and 48 hours after patch removal. No findings were observed in control animals.

The sesitisation rate, i.e. the number of animals showing an alergic response expressed as a percentage of the total number of animals, was determined 24 and 48 hours after patch removal and was 0% in test animals in each case. The corresponding reaction rate in control animals was 0%.

Applicant's summary and conclusion

Interpretation of results:

other: Not classified under CLP criteria

Conclusions:

According to the EEC Directive 2001/59/EEC, 6 August 2001 and the Gefahrstoffverordnung (GefStoffV) of 15 november 1999 (BGB1. I, p. 2233), the test article "ALLSTAB LP 3139 dibasic lead phosphite" can be classified as a "non-sensitiser since no allergic responses were observed in test animals after the adjuvant test according to Magnusson & Kligman.

Executive summary:

The potential skin sensitising properties of the test article "ALLSTAB LP 3139" were assessed in the guinea pig maximisation sensitisation test carried out as an adjuvant test according to the Magnusson & Kligman maximisation test method, using 10 test and 5 control animals in the main test. Following the induction exposure to the test article (50% in petrolatum) or the vehicle petrolatum (control article), the animals of both groups were subjected two weeks later to a challenge exposure with the test article (50% in petrolatum) as well as the control article. Responses to the challenge procedure were evaluated 24 and 48 hours after the end of the exposure period.

Results: No allergic reactions occurred in test animals 24 and 48 hours after the end of the challenge procedure. The sensitisation rate was 0%. No findings were observed in control animals (reaction rate: 0%).

Evaluation: According to nthe EEC Directive 2001/59/EEC, 6 August 2001 and the Gefahrstoffverordnung (GefStoffV) of 15 November 1999 (BGB1. I, p.2233), the test article "ALLSTAB LP 3139 dibasic lead phosphite" can be classified as a "non-sensitiser" since no allergic responses were observed in test animals under the experimental conditions described.