2-methylpyridine

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July 1976

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: This study is similar to the OECD 403 guideline study although only one dose concentration was investigated. This study was conducted prior to the implementation of GLPs.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1976

Report date:

1976

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

yes

Remarks:

only one dose concentration was investigated

GLP compliance:

not specified

Remarks:

Precedes implementation of GLPs.

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-methylpyridine

EC Number:

203-643-7

EC Name:

2-methylpyridine

Cas Number:

109-06-8

Molecular formula:

C6H7N

IUPAC Name:

2-methylpyridine

Details on test material:

Technical grade

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

10 weeks old
males - 240-285g
females - 160-210 g

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

not specified

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: stainless steel, glass chamber
- Exposure chamber volume: 1.5 m3
- Source and rate of air: 5 m3/hr
- Method of conditioning air:
- System of generating particulates/aerosols: stainlee steel nozzle atomizer
- Method of particle size determination: GLC/FID
- Temperature, humidity, pressure in air chamber: 23C

TEST ATMOSPHERE
- Brief description of analytical method used: GLC/FID
- Samples taken from breathing zone: yes/no

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration: highest technically possible

Analytical verification of test atmosphere concentrations:

yes

Remarks:

GLC/FID

Duration of exposure:

4 h

Concentrations:

9.4 mg/l (246 ppm) - highest concentration possible

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

One group of animals was sacrificed 24 hours after beginning of exposure for gross and microscopic examinations on lungs, trachea, larynx and nasal cavity. The remainder of the animals were observed for 14 days.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 9.4 mg/L air (analytical)

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: No mortality occurred in either sex. 9.4 mg/l air is equivalent to 246 ppm alpha-picoline.

Mortality:

0/10

Clinical signs:

other: Humpback posture; eyes closed

Gross pathology:

Normal

Other findings:

Microscopic examination - normal

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category IV

Remarks:

Migrated information LC0 near the lower threshold of 10 mg/l for CLP Category 4, so the LD50 would likely exceed 10 mg/l. Criteria used for interpretation of results: EU

Conclusions:

The 4 hour LC50 of alpha-picoline in rats (5/sex) is greater than 9.4 mg/l (246 ppm), the only concentration tested. There was no mortaltity or
significant clinical signs of toxicity. Gross and microscopic examinations were normal.