Skip directly to site content Skip directly to page options Skip directly to A-Z link Skip directly to A-Z link Skip directly to A-Z link


Centers for Disease Control and Prevention. CDC twenty four seven. Saving Lives, Protecting People
					Search
		×
			NIOSH
			NIOSH
				All CDC
				Submit
			For a full list of topics:A-Z Index
			Advanced Search
		Advanced Search


The National Institute for Occupational Safety and Health (NIOSH)


Facebook
        Twitter
        LinkedIn
        Syndicate





Methyl chloroform																				Related Pages
										May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
**CAS number:** 71–55–6
**NIOSH REL:** 350 ppm (1,900 mg/m3) 15-minute CEILING
**Current OSHA PEL:** 350 ppm (1,900 mg/m3) TWA
**1989 OSHA PEL:** 350 ppm (1,900 mg/m3) TWA, 450 ppm (2,450 mg/m3) STEL
**1993-1994 ACGIH TLV:** 350 ppm (1,910 mg/m3) TWA, 450 ppm (2,460 mg/m3) STEL
**Description of substance:** Colorless liquid with a mild, chloroform-like odor.
**LEL**:. 7.5% (10% LEL, 7,500 ppm)
**Original (SCP) IDLH:** 1,000 ppm
**Basis for original (SCP) IDLH:** The chosen IDLH is based on the statement by MCA [1965] that “humans exposed to 900 to 1,000 ppm experience prompt, though minimal impairment of coordination. Above 1,700 ppm, obvious disturbances of equilibrium in humans have been observed.” Deichmann and Gerarde [1969] stated that “the earliest symptoms of a single vapor exposure are lightheadedness and lassitude. The earliest sign of intoxication is an impaired Romberg test. In humans an abnormal Romberg test is usually observed shortly after exposures to 900 to 1,700 ppm.” Because data are not available to indicate at what concentrations above 1,000 ppm a person’s equilibrium would be affected enough to impede escape, 1,000 ppm is used as the IDLH. AIHA [1961] reported that humans exposed to 800 to 1,000 ppm exhibit early anesthetic effects including incoordination [Stewart et al. 1961; Torkelson et al. 1958]. Browning [1965] reported that several human subjects exposed to 920 ppm for periods ranging from 5 to 45 minutes showed a slight loss of coordination and equilibrium [Stewart et al. 1961].
**Existing short-term exposure guidelines:** American Industrial Hygiene Association [AIHA 1964] Emergency Exposure Limits (EELs):
5-minute EEL: 2,500 ppm
15-minute EEL: 2,000 ppm
30-minute EEL: 2,000 ppm
60-minute EEL: 1,000 ppm
**ACUTE TOXICITY DATA:**
**Lethal concentration data:**

**Species**
    **Reference**
    **LC50 (ppm)**
    **LCLo (ppm)**
    **Time**
    **Adjusted 0.5-hr** **LC (CF)**
    **Derived value**Mouse Rat
    AIHA 1964 Sangyo Igaku 1971
    3,911 18,000
    ----- -----
    2 hr 4 hr
    6,258 ppm (1.6) 36,000 ppm (2.0)
    626 ppm 3,600 ppm**Lethal dose data:**
 
 **Species**
    **Reference**
    **Route**
    **LD50 (mg/kg)**
    **LDLo (mg/kg)**
    **Adjusted LD**
    **Derived value**Rat MouseRabbit
    Pal'gov et al. 1990 Pal'gov et al. 1990Torkelson et al. 1958
    oral oraloral
    9,600 6,0005,660
    ----- ----------
    12,108 ppm 7,568 ppm7,139 ppm
    1,211 ppm 757 ppm714 ppm**Other animal data:** No significant signs of intoxication were seen in rats inhaling 500 ppm, 6 hours per day for 4 days [Savolainen et al. 1977]; in mice inhaling up to 1,300 ppm for 1 hour [Kjellstrand et al. 1985]; in rats inhaling up to 3,000 ppm for 0.5 to 4 hours [Mullin and Krivanek 1982]; or in baboons inhaling up to 1,400 ppm for 4 hours [Geller et al. 1982].
 **Human data:** The onset of central anesthesia has occurred in individuals exposed for up to 7 hours to concentrations approaching 500 ppm [Stewart et al. 1969]. It has been stated that exposure to 900 to 1,000 ppm causes prompt, though minimal impairment of coordination; obvious disturbances in equilibrium have been noted above 1,700 ppm [MCA 1965]. Those exposed to 800 to 1,000 ppm have exhibited early anesthetic effects including incoordination [Stewart et al. 1961]. Volunteers exposed to 920 ppm for 5 to 45 minutes showed a slight loss of coordination and equilibrium [Stewart et al. 1961].
 
 **Revised IDLH:** 700 ppm **Basis for revised IDLH:** The revised IDLH for methyl chloroform is 700 ppm based on acute inhalation toxicity data in humans [MCA 1965; Stewart et al. 1961, 1969].**REFERENCES:**
1. AIHA [1961]. 1,1,1-Trichloroethane (methyl chloroform) (revised 1961). In: Hygienic guide series. Am Ind Hyg Assoc J *22*:509-511.
2. AIHA, Toxicology Committee [1964]. Emergency exposure limits. Am Ind Hyg Assoc J *25*:578-586.
3. Browning E [1965]. Toxicity and metabolism of industrial solvents. New York, NY: Elsevier Publishing Company, p. 257.
4. Deichmann WB, Gerarde HW [1969]. Methylchloroform. In: Toxicology of drugs and chemicals. New York, NY: Academic Press, Inc., pp. 387-388.
5. Geller I, Mendez V, Rippstein W Jr [1982]. Effects of 1,1,1-trichloroethane on a match-to-sample discrimination task in the baboon. J Toxicol Environ Health *9*:783-795.
6. Kjellstrand P, Holmquist B, Jonsson I, Ramare S, Mansson L [1985]. Effects of organic solvents on motor activity in mice. Toxicology *35*:35-46.
7. Marhold JV [1972]. Sbornik Vysledku Toxixologickeho Vysetreni Latek A Pripravku. Czechoslovakia: Institut Pro Vyshovu Vedoucien Pracovniku Chemickeho Prumyclu Praha, p. 28 (in Czechoslovakian).
8. MCA [1965]. Chemical safety data sheet SD-90: properties and essential information for safe handling and use of 1,1,1-trichloroethane. Washington, DC: Manufacturing Chemists Association, pp. 1-14.
9. Mullin LS, Krivanek ND [1982]. Comparison of unconditioned reflex and conditioned avoidance tests in rats exposed by inhalation to carbon monoxide, 1,1,1-trichloroethane, toluene, or ethanol. Neurotoxicol *3*:126-137.
10. Pal’gov VI, Khananaev LI, Goinatskii MG, Gavrilyuk VM, et al. [1990]. Hygienic substantiation of content of methylchloroform in water bodies. Gig Nas Mest *29*:45-49 (in Russian).
11. Sangyo Igaku (Japanese Journal of Industrial Health) [1971]. An experiment of 1,1,1-trichloroethane vapor exposure to mice (supplementary report on the toxicity of 1,1,1-trichloroethane). *13*:226-227 (in Japanese).
12. Savolainen H, Pfaffli P, Tengen M, Vainio H [1977]. Trichloroethylene and 1,1,1-trichloroethane effects on the brain and liver after 5 days intermittent inhalation. Arch Toxicol *38*:229-237.
13. Stewart RD, Gay HH, Erley DS, Hake CL, Schaffer AW [1961]. Human exposure to 1,1,1-trichloroethane vapor: relationship of expired air and blood concentrations to exposure and toxicity. Am Ind Hyg Assoc J *22*:252-262.
14. Stewart RD, Gay HH, Schaffer AW, Duncan SE, Rowe VK [1969]. Experimental human exposure to methyl chloroform vapor. Arch Environ Health *19*:476-472.
15. Torkelson TR, Oyen F, McCollister DD, Rowe VK [1958]. Toxicity of 1,1,1-trichloroethane as determined on laboratory animals and human subjects. Am Ind Hyg Assoc J *19*:353-362.

			
							
								Page last reviewed:  December 4, 2014						Content
							source: 	National Institute for Occupational Safety and Health NIOSH Publications & Products
Immediately Dangerous To Life or Health (IDLH) Values
Table of IDLH Values
Criteria for Determining IDLH Values
Historical Documentation
Original (SCP) Values
Abbreviations for IDLH Documentation
Abbreviations for Journal Titles Follow NIOSH Facebook
Pinterest
Twitter
YouTube
 NIOSH Homepage NIOSH A-Z
Workplace Safety & Health Topics
Publications and Products
Programs
Contact NIOSH


About CDC
					Contact Us
					800-232-4636
 Facebook Twitter Instagram LinkedIn Youtube Pinterest Snapchat
 CONTACT CDC
				Contact Us
							Call 800-232-4636
							Email Us
			ABOUT CDC
				About CDC
							Jobs
							Funding
			POLICIES
				Accessibility
							External Links
							Privacy
							Policies
							No Fear Act
							FOIA
							OIG
							Nondiscrimination
							Vulnerability Disclosure Policy
			CONNECT WITH US
				Facebook
								Twitter
								Instagram
								LinkedIn
							Youtube
								Pinterest
								Snapchat
								Email
			LANGUAGES
				Español
							繁體中文
							Tiếng Việt
							한국어
							Tagalog
							Русский
							العربية
							Kreyòl Ayisyen
							Français
							Polski
							Português
							Italiano
							Deutsch
							日本語
							فارسی
							English


U.S. Department of Health & Human Services
			Accessibility
			External Links
			Privacy
			Policies
			No Fear Act
			FOIA
			Nondiscrimination
			OIG
			Vulnerability Disclosure Policy
			USA.gov


Exit Notification/Disclaimer Policy Close
 Links with this icon  indicate that you are leaving the CDC website. The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website.
					Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website.
					You will be subject to the destination website's privacy policy when you follow the link.
					CDC is not responsible for Section 508 compliance (accessibility) on other federal or private website. Website Disclaimers
 Cancel Continue