Skip directly to site content Skip directly to page options 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





MANGANESE CYCLOPENTADIENYL TRICARBONYL								Related Pages
										*OSHA comments from the January 19, 1989 Final Rule on Air Contaminants Project extracted from 54FR2332 et. seq. This rule was remanded by the U.S. Circuit Court of Appeals and the limits are not currently in force.*
**CAS:** 12079-65-1; **Chemical Formula:** C5H5Mn(CO)3
OSHA formerly had no limit for exposure to manganese cyclopentadienyl tricarbonyl (MCT). The ACGIH has a TLV-TWA of 0.1 mg/m3 (measured as manganese), with a skin notation. The Agency proposed, and the final rule establishes, a permissible exposure limit of 0.1 mg/m3 TWA (measured as manganese), with a skin notation, for this substance. NIOSH (Ex. 8-47, Table N1) concurs that these limits are appropriate.
A Russian study reported that a single two-hour exposure to MCT at 120 mg/m3 was fatal to 80 percent of albino rats, although rabbits, guinea pigs, and rats survived a single two-hour exposure at 20 to 40 mg/m3. Chronic exposure of rats for 11 months at levels averaging 1 mg/m3 for four hours daily showed delayed effects (seven months from onset of exposure) of neuromuscular excitability, evidence of kidney damage, and decreased resistance to infection (Arkhipova, Tolgskaya, and Kochetkova 1965/Ex. 1-1046). The tails of 10 white mice were dipped in a gasoline mixture containing 1 gram MCT per 100 ml; a second group of mice had their tails immersed in gasoline without MCT. An equal number of fatalities were observed in the gasoline plus MCT and gasoline only groups after four or five two-hour applications, and all tails exhibited necrosis. The authors concluded that these effects were caused by the gasoline and not by the MCT (Arkhipova, Tolgskaya, and Kochetkova 1965/Ex. 1-1046). Further studies in rabbits showed that MCT applied dermally as an oil emulsion caused irritation of the skin. These authors also investigated the dermal toxicity of MCT solutions in tetrahydrofuran versus solutions of tetrahydrofuran in oil. All animals whose tails had been dipped in the hydrofuran solution of MCT died within an hour, while animals whose tails had been dipped in pure tetrahydrofuran did not (Arkhipova, Tolgskaya, and Kochetkova 1965/Ex. 1-1046). The same authors concluded that MCT is toxic at low concentrations, has cumulative properties, affects the nervous system, is irritating to the skin, and causes early histological changes in the respiratory tract.
More recent reports describe MCT-induced pulmonary edema and convulsions in the rat (Penney, Hogberg, Traiger, and Hanzlik 1985/Ex. 1-431). The ED(50s) for convulsions were 32 mg/kg orally and 20 mg/kg intraperitoneally; LD(50s) were 24 mg/kg orally and 14 mg/kg intraperitoneally. Necrosis of the bronchiolar tissue and pulmonary parenchymal damage were seen in mice and rats given intraperitoneal doses (Haschek, Hakkinen, Witschi et al. 1982/Ex. 1-1083). No comments other than NIOSH’s were received on MCT.
OSHA has concluded that occupational exposure to MCT poses a risk of neuropathic effects, kidney damage, skin irritation, pulmonary edema, and tissue damage, which together constitute material health impairments. The Agency is therefore establishing an 8-hour TWA PEL of 0.1 mg/m3 for manganese cyclopentadienyl tricarbonyl, with a skin notation, to protect workers against the significant risk of these effects, which have been shown to occur at levels above the new standard.
										
							
								Page last reviewed:  September 28, 2011						Content source:  	National Institute for Occupational Safety and Health NIOSH
1988 OSHA PEL Project Documentation
Index of Chemical Names
Index of CAS Numbers 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