Welcome to the IRIS home page, brought to you by the U.S. Environmental Protection Agency (EPA) and its Office of Research and Development, National Center for Environmental Assessment. IRIS is a database of human health effects that may result from exposure to various substances found in the environment. Click on the Substance File List button to go to a list of the available substance files; then click on any file name on the list to open that file. For more information about IRIS, read this Introduction. Click here for What's New on IRIS, which highlights the most recent changes to IRIS files. See the Glossary of Risk Assessment-Related Terms and the list of Acronyms and Abbreviations for more information explaining terms used in IRIS files. A list of Toxicological Review support documents are available online. They are provided in the Adobe Acrobat Portable Document Format* (PDF). Background Information on methods used by EPA for deriving values in IRIS is available here. Information on Limitations to the Use of IRIS is here. For information on downloading IRIS, see the Stand Alone (Downloadable) IRIS Database page. Here are some LINKS to other sources of environmental health information. EPA is continuously seeking to improve the IRIS home page and the scientific content of IRIS. We welcome your comments and suggestions for improvements. Send comments to the IRIS webmaster by email to Iris.Webmaster@epa.gov For technical questions about the scientific information content in IRIS, please call the U.S. EPA Risk Information Hotline at telephone 1-513-569-7254, or fax to 1-513-569-7159, or email to RIH.IRIS@epamail.epa.gov. Navigation hints: From the opening list of substances, you can click on individual substance names, or the list can be searched with your web browser, such as Netscape or Internet Explorer, by typing the name or Chemical Abstracts Service (CAS) Registry Number at the "Find" command. At any place in an IRIS substance file, use the "Back" command to return to the substance list. To contact the IRIS Webmaster send E-mail to: Iris.Webmaster@epa.gov Last updated: 5 October 1998 URL: http://www.epa.gov/iris/INDEX.HTM