Methyl chloride

Synonyms

Chloromethane; Monochloromethane; [NIOSH] UN1063

Category

Chlorinated Aliphatics

Description

Colorless gas with a faint, sweet odor which is not noticeable at dangerous concentrations; Note: Shipped as a liquefied compressed gas; [NIOSH]

Sources/Uses

Methyl chloride is used as a methylating agent in the synthesis of many organic chemicals. [ACGIH]

Comments

Slurred speech and staggering gait were observed in six workers exposed at 200-400 ppm for at least 2 weeks, but no changes in blood chemistries were found in these six cases. Liver injury has been documented in animal studies. [ACGIH] Possible frostbite from contact with liquid; [NIOSH] In high-dose reproductive studies of mice and rats, methyl chloride causes testicular damage; it causes increased heart valve birth defects in mice only. [Frazier, p. 286-7] Compared to other haloalkanes, methyl chloride is nontoxic to the liver. Steatosis may be observed in high-dose feeding studies of animals. [Zimmerman, p. 333] Has acute effects on the CNS, heart, liver, and kidneys; Possible CNS and reproductive effects after chronic exposure; [ICSC] "Empirical data in support of a skin notation for methyl chloride" [PMID 29708856]

Biomedical References

Yes

50 ppm

100 ppm

100 ppm, Ceiling(OSHA) = 200 ppm(300 ppm for 5-min peak in any 3 hrs)

10 ppm

2000 ppm

10 ppm

LC50 (rat) = 5,300 mg/m3/4H

Explanatory Notes

Odor threshold from AIHA is >10 ppm; Flash point = -45.6 deg C;

Reference Link #2

burn readily

Not appropriate

400 ppm

1,000 ppm

Acute solvent syndrome

Hepatoxic (a) from occupational exposure (secondary effect) or (b) in animal studies or in humans after ingestion

Yes

Yes

Not classifiable

Not Classifiable

Diseases

Occupational diseases associated with exposure to this agent:

• Solvents, acute toxic effect