reaction mass of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-2H -isothiazol-3-one

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Proposed Local Lymph Node Assay protocol prepared by the Interagency Coordinating Committee for Validation of Alternative Methods (ICCVAM) Immunotoxicology Working Group (IWG): National Institutes of Health Publication N° 99-449, Appendix J, 1999

Deviations:

no

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Test material form:

other: Amber Liquid

Details on test material:

- Name of test material (as cited in study report): Kathon™ 886
- Physical state: Amber liquid
- Stability under test conditions: stable at room temperature

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Rohm and Haas Company, Batch No. 6110C010

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature
- Stability under test conditions: Stable at room temperature
- Solubility and stability of the test substance in the solvent/vehicle:
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium:

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: Dilution in acetone:olive oil (4:1, v/v)
- Final dilution of a dissolved solid, stock liquid or gel: 0, 30, 50, 70, 90, 360, 1000 ppm a.i.

OTHER SPECIFICS: Purity of test material was 14%

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/J

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Sprague Dawley, Indianapolis, Indiana, USA.
- Age at study initiation: 68 days old.
- Weight at study initiation: 19.4 to 24.9 g

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, open

Vehicle:

acetone/olive oil (4:l v/v)

Concentration / amount:

25 ul of 0, 30, 50, 70, 90, 360, 1000 ppm a.i.

Day(s)/duration:

3 days

Adequacy of induction:

not specified

No. of animals per dose:

5

Details on study design:

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: Once a day for 3 consecutive days.
- Concentrations: 25 uL; 0, 30, 50, 70, 90, 360, 1000 ppm a.i. TS.

Challenge controls:

Control groups were treated with the vehicle acetone:olive oil (4:1, v/v)

Positive control substance(s):

yes

Remarks:

20 % hexylcinnamaldehyde in acetone/olive oil (4:1, v/v)

Study design: in vivo (LLNA)

Vehicle:

acetone/olive oil (4:1 v/v)

Concentration:

0, 30, 50, 70, 90, 360, 1000 ppm a.i. TS.

No. of animals per dose:

5

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Statistics:

n/a

Results and discussion

In vivo (LLNA)

Results

Results 1

Key result

Parameter:

SI

Value:

> 3

Test group / Remarks:

>= 30 ppm

Results 2

Key result

Parameter:

SI

Value:

> 3

Test group / Remarks:

>= 0.6 microgram a.i./cm2

Any other information on results incl. tables

Detailed information including induction/challenge/scoring schedule for skin sensitisation test

Inductions	LLNA		Observations/Remarks
	Day of treatment	Application
Induction	1, 2, 3	Topical	None
^3H-thymidine	6	Injection	None

Result of skin sensitisation test

Treatment	Measured dose	DPM (mean)	SI (Test/control Ratio)	Results^1
Untreated control	0 ppm	160	--	--
Acetone/olive oil (4:1 v/v)	0 ppm	225	1.0	negative
CMI/MI	30 ppm	776 *	3.4	positive
CMI/MI	50 ppm	1047 *	4.7	positive
CMI/MI	70 ppm	953 *	4.2	positive
CMI/MI	90 ppm	1507 *	6.7	positive
CMI/MI	360 ppm	4612 *	20.5	positive
CMI/MI	1000 ppm	10241 **	45.5	positive
Hexylcinnamaldehyde	20 %	1985 *	8.8	positive
^1Test/control Ratio of 3.0 or greater represents a positive result. * Statistically significant difference compared to the vehicle control group (p<0.05). ** Statistically significant difference compared to the vehicle control group (p<0.01). -- Not applicable. DPM = disintegrations per minute. SI = stimulation index.

Applicant's summary and conclusion

Interpretation of results:

Category 1A (indication of significant skin sensitising potential) based on GHS criteria

Conclusions:

Sensitizer at concentrations greater than 30 ppm a.i. [0.6 microgram a.i./cm2].

Executive summary:

This study was conducted in compliance withthe proposed Local Lymph Node Assay protocol prepared by the Interagency Coordinating Committee for Validation of Alternative Methods (ICCVAM) Immunotoxicology Working Group (IWG): National Institutes of Health Publication N°: 99-449, Appendix J, 1999. There were no Local Lymph Node Assay standard protocol (ICCVAM) deviations.

All concentrations evaluated produced a stimulation index greater than or equal to 3. The results of the study indicate that the test material CMIT/MIT, under the conditions of thestandard protocol (ICCVAM) and according to currently accepted criteria, exhibits a statistically significant, generally dose-related potential to induce contact hypersensitivity in mice.