dichloromethane; methylene chloride

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: Acceptable, well-documented publication, predates OECD guidelines and GLP, minor restrictions in design and reporting, but otherwise adequate for assessment

Data source

Reference

Reference Type:

publication

Title:

The toxicity and narcotic action of mono-chloromono- bromo-methane with special reference to inorganic and volatile bromide in blood, urine and brain.

Author:

Svirbely JL, Highman B, Alford WF, et al.

Year:

1947

Bibliographic source:

J Ind Hyg Toxicol 29 (6), 382-389

Materials and methods

Principles of method if other than guideline:

Mice were exposed for 7 h by whole-body exposure to dichloromethane vapour in a 15-L bell jar.

GLP compliance:

no

Test type:

other: 7-hour whole body exposure

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Dichloromethane

EC Number:

200-838-9

EC Name:

Dichloromethane

Cas Number:

75-09-2

Molecular formula:

CH2Cl2

IUPAC Name:

dichloromethane

Details on test material:

- Name of test material (as cited in study report): di-chloro-methane (methylene chloride)

Test animals

Species:

mouse

Strain:

Swiss Webster

Sex:

not specified

Details on test animals or test system and environmental conditions:

White Swicce mice of approx. 20 g body weight were used

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

Mice were exposed in a bell jar of approximately 15 liters capacity.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

7 h

Concentrations:

53.5, 45.6, 47.7 and 39.9 mg/l (determined) (154000, 13126, 13730 and 11485 ppm)

No. of animals per sex per dose:

20/concentration

Control animals:

no

Details on study design:

The observation period was one day.

Results and discussion

Effect levels

Sex:

not specified

Dose descriptor:

LC50

Effect level:

49 000 mg/m³ air

Based on:

test mat.

Exp. duration:

7 h

Clinical signs:

other: The animals became restless, developed muscular twitchings, uncoordinated movements, labored respiration, and narcosis.

Any other information on results incl. tables

Table 1. The acute toxicity of vapours of dichloromethane for mice.

Concentration in air				Number of fatalities following exposure
Calculated		Determined		Hours
mg/liter	ppm	mg/liter	ppm	8	24
58.70	16.897	53.5	15.400	18/20
55.55	15.990	45.6	13.126	4/20	5/20
52.94	15.239	47.7	13.730	2/20
44.45	12.795	39.9	11.485	0/20

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Because the 4-h LC50 value (calculated from a 7-h value) was 86 mg/L, and no delayed mortality was expected, no classification is needed for acute inhalation toxicity.