Calcium bromide

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1983

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study, according to guidelines

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1983

Report date:

1983

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Test material

Test material information

Constituent 1

Reference substance name:

Calcium bromide

EC Number:

232-164-6

EC Name:

Calcium bromide

Cas Number:

7789-41-5

Molecular formula:

CaBr2

IUPAC Name:

calcium bromide

Details on test material:

A glass bottle containing a white powder identified as 95% Calcium Bromide, was received on July 5, 1983. The test material and container weighed 643.4 grams. and was stored at room temperature. A test material stability statement was provided by the sponsor.

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

not specified

Details on test animals and environmental conditions:

Young adult albino guinea pigs of the Hartley strain were employed as test animals. The guinea pigs were individually housed in wire-bottomed cages suspended above cage board and maintained in a temperature and humidity controlled room with 12-hour lightldark cycles. Each guinea pig was identified with a unique animal number and a card affixed to each cage served for identification. Purina Guinea Pig Chow and water were offered ad libitum. The guinea pigs were acclimated to laboratory conditions for at least 7 days prior to initiation of the study.

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

water

Induction 2

Concentration / amount:

range finding study: 5, 10, 25 and 50% w/v
test: 5% w/v in water for intradermal injection
50% w/w in petrolatum for topical application.

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

water

Challenge 2

Concentration / amount:

range finding study: 5, 10, 25 and 50% w/v
test: 5% w/v in water for intradermal injection
50% w/w in petrolatum for topical application.

No. of animals per dose:

The procedure used was based on the Method of Magnusson & Kligman. In this study three groups of guinea pigs were used: a Primary Irritation Group of four animals, a Test Group of 20 animals and a Naive Control Group of 10 animals. The Naive Control animals were maintained without treatment until the Primary Challenge application. Thirty-four guinea pigs were used in the study.

Details on study design:

Induction Phase:
The Induction Phase involved a combination of intradermal injections with Freund's Complete Adjuvant and a topical application of the test material (test site pretreated) with sodium lauryl sulfate, (SLS). This phase was designed to produce irritation and stimulate the animal's immune system. Only the Test Group animals were treated during this phase.
Challenge Phase:
The Challenge Phase involved a topical application of a nonirritating concentration of test material to a previously unexposed site. All Test Group and Naive Control animals were treated with the challenge application to determine if dermal sensitization had been produced.
Induction (Sensitizing) Phase:
Each of the 20 animals in the Test Group underwent the following treatment.
Intradermal Injections:
An area 4 x 6 cm was clipped along the midline over the shoulder region. Two rows of three-deep intradermal injections were made within the boundaries of a 2 x 4 cm area, one row on each side of the midline as follows:
1. 0.05 ml of the prepared Freundls Adjuvant Solution.
2. 0.05 ml of a 5% w/v aqueous test suspension.
3. 0.05 ml of a 5% w/v solution of test compound in Freundls Adjuvant Solution.
Topical Application:
One week after the injections, the same area was clipped and closely shaved with an electric razor. Since the test agent was nonirritating, the area was pretreated with 10% sodium lauryl sulfate (SLS) in petrolatum 24 hours before the patch was applied. The SLS
was massaged into the skin with a glass rod; no bandage was applied. The test agent (50.0% w/w) in petrolatum was spread over a 2 x 4 cm patch of
Whatman No. 3 filter paper in a thick, even layer. The patch was placed over the injection sites and covered with Blenderme tape. This was secured firmly with Elastoplaste tape wrapped around the torso of the animal. This dressing was left in place for 48 hours.
Challenge Phase:
Two weeks after topical induction all the animals (including the Naive Control Group) received a challenge dose of the highest nonirritating concentration of test material. The hair was removed from a 5 x 5 cm area on the flank by clipping and shaving as before. The test sample was applied on a 2 x 2 cm piece of filter paper in the same fashion as for topical induction. The patch was sealed to the flank for 24 hours under a 4 cm strip of 1- 112 inch Dermicele tape. This was overwrapped with Elastoplaste tape wrapped around the trunk.

Positive control substance(s):

not specified

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

50% w/w

No. with + reactions:

20

Total no. in group:

20

Clinical observations:

severity 1.9

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 50% w/w. No with. + reactions: 20.0. Total no. in groups: 20.0. Clinical observations: severity 1.9.

Results 2

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

0

No. with + reactions:

9

Total no. in group:

10

Clinical observations:

severity 1.2

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 0. No with. + reactions: 9.0. Total no. in groups: 10.0. Clinical observations: severity 1.2.

Results 3

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

50% w/w

No. with + reactions:

11

Total no. in group:

20

Clinical observations:

severity 0.8

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 50% w/w. No with. + reactions: 11.0. Total no. in groups: 20.0. Clinical observations: severity 0.8.

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

0

No. with + reactions:

2

Total no. in group:

10

Clinical observations:

severity 0.5

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 0. No with. + reactions: 2.0. Total no. in groups: 10.0. Clinical observations: severity 0.5.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

Calcium bromide is not a sensitizer. Only 20% of the animals responded to the test material with reactions stronger then the control group. According to directive 67/548/EEC a substance should be classified as sensitizing if "a response of at least 30% of the animals is considered positive".