TOXICOLOGICAL PROFILE FOR HYDRAULIC FLUIDS U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES Public Health Service Agency for Toxic Substances and Disease Registry September 1997 HYDRAULIC FLUIDS ii DISCLAIMER The use of company or product name(s) is for identification only and does not imply endorsement by the Agency for Toxic Substances and Disease Registry. HYDRAULIC FLUIDS iii UPDATE STATEMENT A draft toxicological profile for hydraulic fluids was released in June 1994. This edition supersedes any previously released draft or final profile. Toxicological profiles are revised and republished as necessary, but no less than once every three years. For information regarding the update status of previously released profiles, contact ATSDR at: Agency for Toxic Substances and Disease Registry Division of Toxicology/Toxicology Information Branch 1600 Clifton Road NE, E-29 Atlanta, Georgia 30333 vi *Legislative Background The toxicological profiles are developed in response to the Superfund Amendments and Reauthorization Act (SARA) of 1986 (Public Law 99-499) which amended the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA or Superfund). Section 211 of SARA also amended Title 10 of the U. S . Code, creating the Defense Environmental Restoration Program. Section 2704(a) of Title 10 of the U. S. Code directs the Secretary of Defense to notify the Secretary of Health and Human Services of not less than 25 of the most commonly found unregulated hazardous substances at defense facilities. Section 2704(b) of Title 10 of the U. S. Code directs the Administrator of the Agency for Toxic Substances and Disease Registry (ATSDR) to prepare a toxicological profile for each substance on the list provided by the Secretary of Defense under subsection (b). HYDRAULIC FLUIDS vii CONTRIBUTORS CHEMICAL MANAGER(S)/AUTHORS(S): M. Olivia Harris, M.A. ATSDR, Division of Toxicology, Atlanta, GA Peter McClure, Ph.D.; Lisa Ingerman, Ph.D. Syracuse Research Corporation, Syracuse, NY Robert L. Chessin, M.S.P.H. Research Triangle Institute, Research Triangle Park, NC James J. Corcoran, Ph.D. Research Triangle Institute, Research Triangle Park, NC THE PROFILE HAS UNDERGONE THE FOLLOWING ATSDR INTERNAL REVIEWS: 1. Green Border Review. Green Border review assures consistency with ATSDR policy. 2 . Health Effects Review. The Health Effects Review Committee examines the health effects chapter of each profile for consistency and accuracy in interpreting health effects and classifying end points. 3 . Minimal Risk Level Review. The Minimal Risk Level Workgroup considers issues relevant to substance-specific minimal risk levels (MRLs), reviews the health effects database of each profile, and makes recommendations for derivation of MRLs. 4 . Data Needs Review. The Research Implementation Branch reviews data needs sections to assure consistency across profiles and adherence to instructions in the Guidance. HYDRAULIC FLUIDS ix PEER REVIEW A peer review panel was assembled for hydraulic fluids. The panel consisted of the following members: 1. Dr. C. Carson Conaway, Research Scientist, Mahopac, NY; 2. Dr. Arthur Gregory, Private Consultant, Techto Enterprises, Sterling, VA; 3. Dr. James Hughes, Private Consultant, Piedmont, CA; 4. Dr. Harlee Strauss, Private Consultant, H. Strauss Associates, Inc., Boston, MA; 5. Mr. Edmond Kinkead, Research Scientist, Dayton, OH; and 6. Dr. Charles Ward, Private Consultant, Pittsburgh, PA. These experts collectively have knowledge of hydraulic fluids’s physical and chemical properties, toxicokinetics, key health end points, mechanisms of action, human and animal exposure, and quantification of risk to humans. All reviewers were selected in conformity with the conditions for peer review specified in Section 104(1)( 13) of the Comprehensive Environmental Response, Compensation, and Liability Act, as amended. Scientists from the Agency for Toxic Substances and Disease Registry (ATSDR) have reviewed the peer reviewers’ comments and determined which comments will be included in the profile. A listing of the peer reviewers’ comments not incorporated in the profile, with a brief explanation of the rationale for their exclusion, exists as part of the administrative record for this compound. A list of databases reviewed and a list of unpublished documents cited are also included in the administrative record. The citation of the peer review panel should not be understood to imply its approval of the profile’s final content. The responsibility for the content of this profile lies with the ATSDR. HYDRAULIC FLUIDS 1 1. PUBLIC HEALTH STATEMENT This public health statement tells you about hydraulic fluids and the effects of exposure. The Environmental Protection Agency (EPA) identifies the most serious hazardous waste sites in the nation. These sites make up the National Priorities List (NPL) and are the sites targeted for long-term federal cleanup. Hydraulic fluids have been found in at least 10 of the 1,428 current or former NPL sites. However, it’s unknown how many NPL sites have been evaluated for these substances. As more sites are evaluated, the sites with hydraulic fluids may increase. This is important because exposure to these substances may harm you and because these sites may be sources of exposure. When a substance is released from a large area, such as an industrial plant, or from a container, such as a drum or bottle, it enters the environment. This release does not always lead to exposure. You are exposed to a substance only when you come in contact with it. You may be exposed by breathing, eating, or drinking the substance or by skin contact. If you are exposed to hydraulic fluids, many factors determine whether you’ll be harmed. These factors include the dose (how much), the duration (how long), and how you come in contact with it. You must also consider the other chemicals you’re exposed to and your age, sex, diet, family traits, lifestyle, and state of health. 1 .1 WHAT ARE HYDRAULIC FLUIDS? Hydraulic fluids are a very large class of materials that are used in machines and equipment to. transfer pressure from one point to another. They are used in many ways including all fluids for car automatic transmissions, brakes, and power steering. Hydraulic fluids are also used in many machines like tractors and other farm equipment, forklift trucks, bulldozers, and other construction equipment, and airplanes. In industry, hydraulic fluids are used in machines that push, lift, pull, turn, and hold things. This profile covers only three of the many types of hydraulic HYDRAULIC FLUIDS 2 1. PUBLIC HEALTH STATEMENT fluids: (1) mineral oil, (2) organophosphate ester, and (3) polyalphaolefin. These types are among the most commonly used today. The trade names of typical hydraulic fluids covered in this profile include Durad®, Fyrquel®, Skydrol®, Houghton-Safe®, Pydraul®, Reofose, Reolube®, and Quintolubric®. Hydraulic fluids used in cars are not specifically covered in this profile. Some hydraulic fluids have a bland oily smell, while others have no smell. Mineral oil and polyalphaolefm hydraulic fluids are mixtures that have oil in them and will burn. Oil-in-water hydraulic fluids (a special type of mineral oil hydraulic fluid) do not burn because they contain water. Organophosphate ester hydraulic fluids are mostly made without oil and will not burn unless there is a flame directly on them; once the flame is removed, these fluids will stop burning. Because they do not burn, organophosphate ester hydraulic fluids are used in airplanes and other places where fues are very undesirable. Mineral oil hydraulic fluids are produced from crude oil. Organophosphate ester and polyalphaolefin hydraulic fluids are manufactured. All hydraulic fluids contain many ingredients which reduce wear, make the fluid flow better, and make it thinner when it is cold. More than 200 million gallons of hydraulic fluids are sold each year in the United States. See Chapters 3 and 4 for more information on hydraulic fluids. 1.2 WHAT HAPPENS TO HYDRAULIC FLUIDS WHEN THEY ENTER THE ENVIRONMENT? Hydraulic fluids can enter the environment from spills and leaks in machines that use them and from leaky storage tanks. If spilled on soil, some of the ingredients in the hydraulic fluids mixture may stay on the top, while others may sink into the groundwater. How fast the ingredients move through soil depends on many things. These include how much is spilled, how much rain falls on the spill, and the type of soil (for example, hydraulic fluids will move quickly in sandy soil, but will move slower in heavy clay). In water, some ingredients of hydraulic fluids will transfer to the bottom and stay there. Fish may contain some hydraulic fluid ingredients if they live near places that make or use a lot of it. Eventually, the ingredients of hydraulic fluids are degraded in the environment, but complete degradation may take more than a year. Scientists know a little about HYDRAULIC FLUIDS 3 1. PUBLIC HEALTH STATEMENT how some of the ingredients in hydraulic fluids break down in the environment, but they know almost nothing about how toxic these breakdown products are. See Chapters 4 and 5 for more information on what happens to hydraulic fluids in the environment. 1.3 HOW MIGHT I BE EXPOSED TO HYDRAULIC FLUIDS? Exposures to hydraulic fluids occur mainly in workers using hydraulic equipment and in people who work on cars or tractors that use the fluids. Most people are exposed when fluids spill or leak on the skin, when the fluid is changed, or when the fluid reservoirs are filled. Low levels of hydraulic fluids may occur in the air near machines that use them. Understanding environmental levels of hydraulic fluids is very difficult because the ingredients in hydraulic fluids are used in many products other than hydraulic fluids. For example, mineral oil is an ingredient in both motor oil and mineral oil hydraulic fluids. In the environment, mineral oil from both sources would appear to be the same. Polyalphaolefin hydraulic fluids have chemical components and potential applications similar to mineral oil hydraulic fluids.