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





PHENYLHYDRAZINE								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:** 100-63-0; **Chemical Formula:** C6H5NHNH2
OSHA’s former limit for phenylhydrazine was 5 ppm TWA as an 8-hour, with a skin notation. The ACGIH has a TLV-TWA of 5 ppm with a STEL of 10 ppm, and a skin notation. NIOSH (1978e/Ex. 1-263) recommends that workplace exposures not exceed 0.14 ppm as measured over a two-hour period. OSHA proposed to retain the PEL of 5 ppm as an 8-hour TWA and to add a STEL of 10 ppm, with a skin notation, and these limits are established in the final rule. Phenylhydrazine may be either yellow crystals or an oily liquid that darkens on exposure to air and light.
No data are available on the effects of phenylhydrazine resulting from inhalation. The ACGIH limits are based on the high acute toxicity of the compound when administered orally or subcutaneously to animals; single doses on the order of 20 mg/kg have resulted in the death of dogs within 22 days (Hesse, Franke, and Hering 1935/Ex. 1-785) and produced a marked decrease in erythrocyte count in rodents (von Oettingen and Deichmann-Greubler 1936/Ex. 1-771). Anemia and hemolysis are the characteristic responses seen in animals fed or injected with phenylhydrazine.
In its criteria document on the hydrazines, NIOSH (1978e/Ex. 1-263) reviewed four studies on the carcinogenicity of phenylhydrazine in mice. One study (Toth and Shimizu 1976/Ex. 1-675) found significant increases in blood vessel tumors. Another study (Clayson, Biancifiori, Milia, and Santilli 1966, as cited in ACGIH 1986/Ex. 1-3, p. 477) reported increased incidences of lung adenomas and adenocarcinomas. Two other studies (Roe, Grant, and Millican 1967/Ex. 1-659; Kelly, O’Gara, Yancy et al. 1969/Ex. 1-703) were negative. NIOSH concluded that phenylhydrazine should be considered a potential human carcinogen and recommended that exposures not exceed 0.14 ppm over a two-hour sampling period, which represents the lowest level that can be detected reliably. The ACGIH (1986/Ex. 1-3) has placed phenylhydrazine on its A2 (suspected human carcinogens) list.
NIOSH (Ex. 8-47, Table N6B; Tr. 3-97 to 3-98), the Workers Institute for Safety and Health (WISH) (Ex. 116), the AFL-CIO (Ex. 194), the Oil Chemical and Atomic Workers (Tr. 9-218), and the American Industrial Hygiene Association (Ex. 8-16) were of the opinion that OSHA’s proposed revision of the PEL for phenylhydrazine was not sufficiently protective. NIOSH (Ex. 8-47) indicated that phenylhydrazine may be a suitable candidate for an individual 6(b) rulemaking. Typical of the views of these commenters was the statement of WISH (Ex. 116), which commented that the ACGIH had, at one time, considered reducing its 5-ppm TLV-TWA, and cited a 1974 study in which rabbits given intravenous injections of phenylhydrazine showed blood and liver effects. The evidence of phenylhydrazine’s possible carcinogenicity was also cited by WISH as additional support for a more stringent limit. In response, OSHA notes that the Agency is also concerned about the evidence for these adverse effects of phenylhydrazine exposure and will continue to monitor and evaluate the toxicologic literature on phenylhydrazine to determine whether there is a need in the future for a further reduction in the occupational exposure limit.
However, at the present time, OSHA is retaining the 5-ppm 8-hour TWA and adding a 10-ppm STEL for phenylhydrazine; the skin notation is also retained. The Agency concludes that these two limits will work together to keep workplace exposures well controlled and will reduce the significant health risks associated with exposure to this substance. These risks include acute blood-related toxicity and may also include cancer; these effects clearly constitute material impairments of health. OSHA finds that the TWA and STEL limits established in the final rule will substantially reduce these significant risks.
										
							
								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