3,5-dimethylpyridine

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation / corrosion

Remarks:

in vitro

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Similar to a guideline method but not performed under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 435 (In Vitro Membrane Barrier Test Method for Skin Corrosion)

Principles of method if other than guideline:

An in vitro barrier test method (OECD 435) was employed, using a Color Detection System (CDS) for an irritant. The material was placed on a biobarrier situated on a permeable support membrane, and the time to penetration of the biobarrier and membrane into the indicator solution was measured in 4 replicates.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

3,5-dimethylpyridine

EC Number:

209-708-6

EC Name:

3,5-dimethylpyridine

Cas Number:

591-22-0

Molecular formula:

C7H9N

IUPAC Name:

3,5-dimethylpyridine

Test material form:

other: liquid

Details on test material:

no data

Test animals

Species:

other: in vitro

Strain:

other: in vitro

Test system

Type of coverage:

other: in vitro

Preparation of test site:

other: in vitro

Vehicle:

other: in vitro

Controls:

other: positive and negative control substances were included in the test procedure.

Details on study design:

The Corrositex (R) test method was used to predict the in vivo corrosive potential of a chemical compound or mixture by using as an endpoint the time it takes for the chemical to permeate through or destroy a synthetic biobarrier. When the chemical has passed through this biobarrier, a visual change is produced in a proprietary Chemical Detection System (CDS). Qualification of the material as appropriate for testing in this procedure is first undertaken by applying either 150 ml of a liquid or 100 mg of a solid into an aliquot of the CDS reagent and observing it for the presence of any detectable change. If a physical or color change is observed, the sample is judged to be compatible with the detection solution and the remainder of the test is performed. The second step of the Corrositex test utilizes appropriate indicator solutions to permit categorization of the test sample as either a Category 1 or Category 2 material. Category 1 materials are typically strong acids/bases, while Category 2 materials are typically weak acids/bases. The third step in the test is performed by applying the test sample to the biobarrier. When the chemical permeates through or destroys the full thickness of this biobarrier, it comes into contact with the CDS which then undergoes a simple color change. This color change is visually observed and the time required for the color change to occur is recorded. Positive and negative controls are analyzed concurrently to confirm the test's validiy. Four replicates of the test substance, applied neat to the the biobarrier, were examined. The time (in minutes, mean ± SD) to breakthough (color change) was calculated.

Results and discussion

In vivo

Results

Irritation parameter:

other: Corrosion

Basis:

mean

Time point:

other: Not applicable

Score:

> 60

Reversibility:

other: not applicable

Remarks on result:

other: Mean time to color change was > 60 min, indicating "noncorrosive"

Irritant / corrosive response data:

The mean time to color change was > 60 min for four replicates of the test material, tested in an indicator solution identifying irritants. The duration of time > 60 minutes indicates the substance is noncorrosive.

Other effects:

The indicator CDS system was for Irritation, Category 2, based on the structure of the test material.

Any other information on results incl. tables

Table 1: Designation of UN Packing Groups

	Corrositex Time (minutes)
Category 1 (based on Indicator solutions)	0 to 3 min.	>3 to 60 min.	>60 to 240 min.	>240 min.
Category 2 (based on Indicator solutions)	0 to 3 min.	>3 to 30 min.	>30 to 60 min.	>60 min.
Result	UN Packing Group I	UN Packing Group II	UN Packing Group III	Noncorrosive

Table 2: Summary of Test Results

IVI#:C2914	Corrositex Time (minutes)
Sample:3,5-Lutidine	Replicate #1:> 60
Conc. Tested:Neat	Replicate #2:> 60
pH:n/a	Replicate #3:> 60
Category:2	Replicate #4:> 60
Packing Group:NC	Mean±SD:         > 60

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant)

Remarks:

Migrated information Criteria used for interpretation of results: expert judgment

Conclusions:

3,5-Dimethylpyridine was tested neat in a Corrositex (R) Biobarrier membrane penetration test. The substance remained on the biobarrier for > 60 minutes, using a color detection system for Category 2 (irritants). This result indicates that the substance is an irritant, but is not corrosive.