4-methylmorpholine

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

No data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Acceptable report similar to guideline study (IHT; no GLP, TS purity not specified; animals were observed for only 7 days, limited documentation, exposure period of up to 1 hour, concentration of test substance in air mixture was not verified analytically; mortality occurred after 30 min/1 hour exposure).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1964

Report date:

1964

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Version / remarks:

(adopted on 1981, 12th May; inhalation hazard test)

Deviations:

yes

Remarks:

animals were observed for only 7 days, limited documentation, exposure period of up to 1 hour, concentration of test substance in air mixture was not verified analytically

GLP compliance:

no

Test type:

other: inhalation hazard test

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4-methylmorpholine

EC Number:

203-640-0

EC Name:

4-methylmorpholine

Cas Number:

109-02-4

Molecular formula:

C5H11NO

IUPAC Name:

4-methylmorpholine

Test material form:

liquid

Specific details on test material used for the study:

- Name of test material (as cited in study report): 4-Methyl-morpholin

Test animals

Species:

rat

Strain:

not specified

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
no data

ENVIRONMENTAL CONDITIONS
no data

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

clean air

Details on inhalation exposure:

The test demonstrates the toxicity of an atmosphere saturated with vapors of the volatile components of a test substance at 20 °C.
Young adult laboratory rats, 3 or 6 per sex, were exposed sequentially to the vapors generated by bubbling 200 L/h air through a substance column of about 5 cm above a fritted glass disc in a glass cylinder for 10 or 30 min and 1 hour.

Analytical verification of test atmosphere concentrations:

no

Remarks:

No analytical determination of the atmosphere concentrations was performed. The nominal concentration was calculated as quotient of the amount of test substance weight loss during exposure, and the amount of air used during exposure.

Duration of exposure:

ca. 10 - ca. 60 min

Remarks on duration:

10 and 30 minutes as well as 1 hour

Concentrations:

119.5-130.2 mg/l

No. of animals per sex per dose:

3-6

Control animals:

no

Details on study design:

- Duration of observation period following administration: 7 days
- Frequency of observations and weighing: all rats of a exposure group were weighed before the study and after the 7 days of exposure (survivers), observations were performed, frequency not stated
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, gross pathology

Statistics:

no data

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

other: IHT

Effect level:

ca. 119.5 - ca. 130.2 mg/L air (nominal)

Based on:

test mat.

Exp. duration:

1 h

Remarks on result:

other: All 12 rats survived an exposure to the saturated vapour for 10 minutes. Exposure for 30 min and 1 hour led to death (5/6 and 6/6 animals died respectively).

Mortality:

6/6 rats died when exposed to the saturated vapour of the test substance for 1 hour.
5/6 rats died when exposed to the saturated vapour of the test substance for 30 min.
All 12 rats survived when exposed to the saturated vapour of the test substance for 10 min.

Clinical signs:

other: 1 hours exposure: vigorous attempts to escape, intense secretion from eyes and nose, dyspnoea, all animals died during the exposure. 30 min exposure: vigorous attempts to escape, intense secretion from eyes and nose, dyspnoea, after some time bloody secre

Body weight:

No data

Gross pathology:

Blood in the lung and the nose was observed in 3 rats of the 30 min exposure group, no other findings were noted in the other groups, organs were without findings.

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Remarks:

inconclusive as no LC50 value could be determined in this study

Conclusions:

In this acute inhalation toxicity test, following mortalities were observed: 6/6 rats died when exposed to the saturated vapour of the test substance for 1 hour, 5/6 rats died when exposed to the saturated vapour of the test substance for 30 min and all 12 rats survived when exposed to the saturated vapour of the test substance for 10 min. The study is considered inconclusive as no LC50 value could be determined in this study.