3-methylpyridine

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Reliable with restrictions; acceptable, well-documented publication/study report which meets basic scientific principles.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Rats were exposed (nose-only) to vapours of test material for a single 4 hour period. Clinical signs were note. Lethality and weight gain was followed for 14 days after exposure to determine levels associated with acute lethality.

GLP compliance:

not specified

Test type:

standard acute method

Test material

Test material information

Constituent 1

Reference substance name:

3-methylpyridine

EC Number:

203-636-9

EC Name:

3-methylpyridine

Cas Number:

108-99-6

Molecular formula:

C6H7N

IUPAC Name:

3-methylpyridine

Details on test material:

98.5% pure

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male

Details on test animals or test system and environmental conditions:

Rats were 8 weeks of age, weighing between 237 and 279 g.

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

nose only

Vehicle:

not specified

Analytical verification of test atmosphere concentrations:

yes

Remarks:

gas chromatography

Duration of exposure:

4 h

Concentrations:

1300 and 3300 ppm, equivalent to about 5000 mg/m3 and 12,500 mg/m3, respectively

No. of animals per sex per dose:

6 rats/sex/group

Control animals:

no

Details on study design:

Rats were weighed prior to exposure and observed during exposure. Surviving rats were weighed and observed daily for 14 days post exposure, weekends excluded except when deemed necessary by the rats’ condition. Except during exposure, feed and water were available ad libitum.

Results and discussion

Effect levels

Sex:

male

Dose descriptor:

LC50

Effect level:

> 1 300 - < 3 300 ppm

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: Deaths at 1300 ppm: 0/6, Deaths at 3300 ppm: 6/6.

Mortality:

Deaths at 1300 ppm: 0/6,
Deaths at 3300 ppm: 6/6.

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category IV

Remarks:

Migrated information 2500 < LC50 <10000 ppm. Criteria used for interpretation of results: EU

Conclusions:

The lethality of inhalation exposure to 3-picoline (3-methylpyridine) was investigated in male rats. The LC50 was between 1300 ppm and 3300 ppm, which spans 2 hazard categories. No deaths were observed at the low concentration of 1300 ppm. A middle value of 2500 ppm is chosen as the LD50, equivalent to 9521 mg/m3 or 9.5 mg/L, which is at the threshold between two classification categories. Considering the consistent behaviour of this substance with other category members, and the fact that two other category members show inhalation lethality at ranges above 10 mg/L, this substance is placed in GHS category 4.