4-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: Similar to a guideline study but preceeds establishment of guidelines and GLP.

Data source

Reference

Reference Type:

review article or handbook

Title:

Unnamed

Year:

1972

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 433 draft (Acute Inhalation Toxicity: Fixed Concentration Procedure) (not officially approved)

Version / remarks:

preceeds establishment of guideline

GLP compliance:

not specified

Test type:

fixed concentration procedure

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4-methylpyridine

EC Number:

203-626-4

EC Name:

4-methylpyridine

Cas Number:

108-89-4

Molecular formula:

C6H7N

IUPAC Name:

4-methylpyridine

Details on test material:

no data

Test animals

Species:

rat

Strain:

not specified

Sex:

male

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Duration of exposure:

> 0.15 - < 2.5 h

Concentrations:

Average concentration was 17.5 g/m3 or 17500 mg/m3.

No. of animals per sex per dose:

6

Control animals:

not specified

Details on study design:

Exposure occurred in a stainless steel chamber of 35 L capacity.
A concentrated atmosphere of vapour was generated by passing a stream of air through 109 g of substance in a 500 ml Erlenmyer flask. Vapours passed through a 1-liter bottle to remove droplets and then into the exposure chamber. Air flow through the sample was 4.0 liters/min as measured through a calibrated rotameter. No supplemental air was introduced as oxygen content was sufficient.

Temperature of the chamber: 78 degrees F or 25.6 degrees C.
Relative humidity of the chamber: 70%.

Results and discussion

Effect levels

Key result

Sex:

male

Dose descriptor:

LC100

Effect level:

17 500 mg/m³ air (nominal)

Based on:

test mat.

Remarks on result:

other: Equivalent to 4075 ppm

Mortality:

All animals died within 2.5 hours.

Clinical signs:

other: Increasing weakness, labored breathing, collapse and death.

Gross pathology:

hemorrhagic lungs and hyperemic livers.

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category III

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

An acute inhalation toxicity (limit) test was conducted in a whole body protocol using male rats with 4-methylpyridine at a concentration of 17500 mg/m3. All rats died within 2.5 h of exposure. The LC50 is less than 17500 mg/m3 or 4075 ppm.