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Integrated Risk Information System (IRIS); Announcement of 2008 Program

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Environmental Protection Agency (EPA).


Notice; request for information.


The U.S. Environmental Protection Agency (EPA) is announcing the IRIS 2008 agenda and requesting scientific information on health effects that may result from exposure to the chemical substances on the agenda, including assessments that EPA is starting this year. The Integrated Risk Information System (IRIS) is an EPA database that contains the Agency's scientific positions on human health effects that may result from exposure to chemical substances in the environment. Assessments currently in progress are listed in this notice.


While EPA is not expressly soliciting comments on this notice, the Agency will accept information related to the substances included herein. Please submit any information in accordance with the instructions provided below.


Please submit relevant scientific information identified by docket ID number EPA-HQ-ORD-2007-0664, online at (EPA's preferred method); by e-mail to; mailed to Office of Environmental Information (OEI) Docket (Mail Code: 2822T), U.S. Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; or by hand delivery or courier to EPA Docket Center, EPA West, Room 3334, 1301 Constitution Ave., NW., Washington, DC, between 8:30 a.m. and 4:30 p.m. Monday through Friday, excluding legal holidays. Comments on a disk or CD-ROM should be formatted in Word or as an ASCII file, avoiding the use of special characters and any form of encryption, and may be mailed to the mailing address above.

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For information on the IRIS program, contact Dr. Abdel-Razak Kadry, IRIS Program Director, National Center for Environmental Assessment, (mail code: 8601D), Office of Research and Development, U.S. Environmental Protection Agency, Washington, DC 20460; telephone: (202) 564-1645, facsimile: (202) 565-0075; or e-mail: Start Printed Page 72716

For general questions about access to IRIS, or the content of IRIS, please call the IRIS Hotline at (202) 566-1676 or send electronic mail inquiries to

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IRIS is a database of human health effects that may result from exposure to various chemical substances found in the environment. (EPA notes that information in the IRIS database has no preclusive effect and does not predetermine the outcome of any rulemaking. When EPA uses such information to support a rulemaking, the scientific basis for, and the application of, that information are subject to comment.) IRIS currently provides information on health effects associated with more than 500 chemical substances.

The database includes chemical-specific summaries of qualitative and quantitative health information in support of the first two steps of the risk assessment process, i.e., hazard identification and dose-response evaluation. Combined with specific situational exposure assessment information, the information in IRIS is an important source in evaluating potential public health risks from environmental contaminants.

EPA's overall process for developing IRIS assessments consists of: (1) Publication of an annual Federal Register announcement of EPA's IRIS agenda and call for scientific information from the public on selected chemical substances; (2) a comprehensive search of the current scientific literature; (3) development of a draft IRIS health assessment utilizing state of the art scientific methods and guidelines; (4) internal EPA review of the draft assessment; (5) interagency review of the draft assessment; (6) public comment followed by independent external peer review of the draft assessment; (7) a public external peer review meeting related to the draft assessment; (8) preparation of a final IRIS assessment that reflects public comments and independent expert review; (9) interagency review of the final assessment; (10) EPA review and clearance of the final assessment; and (11) posting of the final IRIS assessment on the IRIS database (​iris).

The IRIS Annual Agenda

Each year, EPA develops a priority list of chemicals and an annual agenda for the IRIS program and announces new assessments under review. EPA uses five general criteria to set these priorities: (1) Potential public health impact; (2) EPA statutory, regulatory, or program-specific implementation needs; (3) availability of new scientific information or methodology that might significantly change the current IRIS information; (4) interest to other governmental agencies or the public; and (5) availability of other scientific assessment documents that could serve as a basis for an IRIS assessment. The decision to assess any given chemical substance depends on available Agency resources. Availability of risk assessment guidance, guidelines, and science policy decisions may also have an impact on the timing of EPA's decision to assess a chemical substance.

EPA is soliciting public involvement in assessments on the IRIS agenda, including new assessments starting in 2008. While EPA conducts a thorough literature search for each chemical substance, there may be unpublished studies or other primary technical sources that are not available through the open literature. EPA would appreciate receiving scientific information from the public during the information gathering stage for the assessments listed in this notice. Interested persons should provide scientific analyses, studies, and other pertinent scientific information. While EPA is primarily soliciting information on new assessments starting in 2008, the public may submit information on any chemical substance at any time.

This notice provides: (1) A list of IRIS assessments in progress; (2) a list of new IRIS assessments starting in 2008; and (3) instructions to the public for submitting scientific information to EPA pertinent to the development of assessments.

Assessments in Progress

The following assessments are underway. The status and planned milestone dates for each assessment can be found on the IRIS Track system, accessible from the IRIS database. All health endpoints due to chronic exposure, cancer and noncancer, are being assessed unless otherwise noted. For all endpoints assessed, both qualitative and quantitative assessments are being developed where information is available.

Substance nameCAS No.
arsenic, inorganic7440-38-2
beryllium (cancer)7440-41-7
butyl benzyl phthalate85-68-7
carbon tetrachloride56-23-5
cerium oxide and cerium compounds1306-38-3
chlordecone (kepone)143-50-0
dibutyl phthalate84-74-2
cis- 1,2-dichloroethylene156-59-2
trans- 1,2-dichloroethylene156-60-5
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dichloromethane (methylene chloride)75-09-2
ethyl tert-butyl ether637-92-3
ethylene dichloride107-06-2
ethylene glycol monobutyl ether111-76-2
ethylene oxide (cancer)75-21-8
hexahydro-1,3,5-trinitro-triazine (RDX)121-82-4
hydrogen cyanide74-90-8
methyl tert-butyl ether (MTBE)1634-04-4
nickel (soluble salts)(various)
perfluorooctanoic acid—ammonium salt3825-26-1
perfluorooctane sulfonate—potassium salt2795-39-3
polycyclic aromatic hydrocarbon (PAH) mixturesvarious
polybrominated diphenyl ethers
polychlorinated biphenyls (PCBs) (noncancer)1336-36-3
refractory ceramic fibersnot applicable
and related compoundsvarious
tetrachloroethylene (perchloroethylene)127-18-4
trichloroacetic acid76-03-9
uranium compounds7440-61-1
vinyl acetate108-05-4

The following assessments were completed in FY2006 and FY2007: n-hexane; phosgene; 1,1,1-trichloroethane; 2,2,4-trimethylpentane. The following assessments are being withdrawn from the IRIS agenda at the request of the EPA Office of Water: aldicarb, aldicarb sulfoxide, and aldicarb sulfone. Assessments of these chemicals will be completed by the EPA Office of Pesticide Programs. The following assessments are being withdrawn by the EPA Office of Research and Development: acrolein (acute), benzene (acute), ethylene oxide (acute), phosgene (acute), hexachlorocyclopentadiene (acute), and hydrogen sulfide (acute).

IRIS assessments for all substances listed as on-going assessments will be provided on the IRIS Web site at​iris as they are completed. This publicly available Web site is EPA's primary location for IRIS documents. In addition, external peer review drafts of IRIS assessments are posted for public information and comment. These drafts will continue to be accessible via the IRIS and NCEA Web sites. Note that these drafts are intended for public information.

Information Requested on New Assessments for 2008

EPA developed a list of priority chemicals for 2008 from nominations from the EPA programs and from the public received in response to the December 22, 2006, Federal Register notice requesting public nominations (71 FR 77017). The following chemicals were nominated and have been selected for inclusion in the IRIS agenda.

Substance nameCAS No.
tert-amyl methyl ether994-05-8
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bisphenol A80-05-7
carbonyl sulfide463-58-1
chromium VI18540-29-9
diethyl phthalate84-66-2
diisopropyl ether108-20-3
hexabromocyclododecane (mixed stereoisomers)3194-55-6; 25637-99-4
toxaphene (weathered)8001-35-2
vanadium pentoxide1314-62-1

EPA is conducting literature searches for these chemicals in 2008. Based on the results of the literature searches and as EPA resources allow, assessments will be started for those chemicals with data that may support development of one or more toxicity values.

With this IRIS agenda announcement, EPA is starting a new process to actively solicit information from the public at the beginning of assessment development. As literature searches are completed, the results will be posted on the IRIS Web site (​iris). The public is invited to review the literature search results and submit additional information to EPA. Literature search results are currently available at​iris for tert-amyl methyl ether, biphenyl, n-butanol, tert-butanol, carbonyl sulfide, diethyl phthalate, diisopropyl ether, hexabromocyclodecane, weathered toxaphene, tungsten, and urea. Additional literature searches will be posted in batches as they are completed. Availability will be announced in the Federal Register. Instructions on how to submit information are provided below under General Information.

While the annual prioritization process responds to the needs expressed by IRIS users, EPA is also systematically updating the IRIS database. On a cyclical basis, the IRIS Program conducts screening-level reviews of the available scientific literature for all chemicals in the IRIS database that are not under active reassessment. The purpose of EPA's screening level review is to reach preliminary determinations regarding the likelihood that a full reassessment based on an evaluation of new health effects literature could potentially result in significant changes to existing toxicity values or cancer weight-of-evidence designations. The process consists of a preliminary search and review of the literature through standard toxicological bibliographic databases (titles and abstracts) and selected literature compilations to identify new major studies that have become available since the existing IRIS assessment was completed. The results of the screening-level review for an IRIS chemical can be found on the IRIS Web site (​iris) by selecting the specific IRIS Summary of Interest.

EPA has started a program to systematically update assessments on the IRIS database. This program addresses assessments that were completed more than 10 years ago and have one or more toxicity values for which new data or new methods of analysis have been identified that could possibly change a toxicity value or a cancer weight-of-evidence descriptor. EPA is developing a protocol for prioritizing and updating these assessments.

We continue to request the submission of any scientific information that you would like EPA to consider in confirming the results of the literature screening review and literature screen verification. Instructions for submitting information are provided below.

General Information

As of Monday, November 28, 2005, EPA's EDOCKET was replaced by the Federal Docket Management System (FDMS), the new federal government-wide system. FDMS was created to provide a single point of access to all federal rulemaking activities. All materials previously found in EDOCKET are now available on the internet at

A. How Can I Get Copies of Related Information?

EPA has established an official public docket for this action under Docket ID No. EPA-HQ-ORD-2007-0664. The official public docket is the collection of materials that is available for public viewing at the Office of Environmental Information (OEI) Docket in the EPA Docket Center, EPA West, Room 3334, 1301 Constitution Ave., NW., Washington, DC. The EPA Docket Center Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the OEI Docket is (202) 566-1752.

An electronic version of the public docket is available through EPA's electronic public docket and comment system. EPA Dockets at may be used to submit or view public submissions, to access the index listing of the contents of the official public docket, and to access those documents in the public docket that are available electronically. Once in the system, select “search,” then key in the appropriate docket identification number.

It is important to note that EPA's policy is that public submissions, whether submitted electronically or in paper, will be made available for public viewing in EPA's electronic public docket as EPA receives them and without change, unless the submission contains copyrighted material, confidential business information (CBI), or other information whose disclosure is restricted by statute. Information claimed as CBI and other information whose disclosure is restricted by statute are not included in the official public docket or in EPA's electronic public docket. EPA's policy is that copyrighted material, including copyrighted material contained in a public comment, will not be placed in EPA's electronic public docket but will be available only in printed, paper form in the official public docket. Although not all docket Start Printed Page 72719materials may be available electronically, you may still access any of the publicly available docket materials through the EPA Docket Center.

B. How and to Whom Do I Submit Information?

Information on chemical substances listed in this notice may be submitted as provided in the ADDRESSES section. If you submit electronic information, EPA recommends that you include your name, mailing address, and an e-mail address or other contact information in the body of your submission and with any disk or CD ROM you submit. This ensures that you can be identified as the submitter of the information and allows EPA to contact you in case EPA cannot read your information due to technical difficulties or needs further information on the substance of your submission. Any identifying or contact information provided in the body of submitted information will be included as part of the submission information that is placed in the official public docket, and made available in EPA's electronic public docket. If EPA cannot read your information due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your information.

EPA's preferred method for receiving submissions is via EPA's electronic public docket. The electronic public docket system is an “anonymous access” system, which means EPA will not know your identity, e-mail address, or other contact information unless you provide it in the body of your submission. In contrast to EPA's electronic public docket, EPA's electronic mail (e-mail) system is not an “anonymous access” system. If you send e-mail directly to the docket without going through EPA's electronic public docket, your e-mail address is automatically captured and included as part of the submission that is placed in the official public docket, and made available in EPA's electronic public docket.

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Dated: December 6, 2007.

Peter Preuss,

Director, National Center for Environmental Assessment.

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[FR Doc. E7-24844 Filed 12-20-07; 8:45 am]