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Draft Toxicological Review of Dichlorobenzenes and Integrated Risk Information System (IRIS) Summary for 1,2-DCB, 1,3-DCB and 1,4-DCB

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Environmental Protection Agency.


Notice of external peer-review panel meeting.


The U.S. Environmental Protection Agency (EPA) is announcing an external peer-review panel meeting to review the external review draft documents entitled, “Toxicological Review of Dichlorobenzenes and IRIS Summary for 1,2-DCB, 1,3-DCB and 1,4-DCB” (NCEA-S-1618). The document was prepared by EPA's National Center for Environmental Assessment (NCEA) of the Office of Research and Development. EPA will use comments and recommendations from the expert panel meeting to finalize the draft document.


The peer-review panel workshop will begin on Thursday, February 12, 2004, at 8 a.m. and ends at 5 p.m Eastern Standard Time. The 30-day public comment period begins January 30, 2004, and ends March 1, 2004. Technical comments must be postmarked by March 1, 2004.


The external peer-review panel meeting will be held at the Andrew W. Briedenbach Environmental Research Center, U.S. EPA, 26 W. Martin Luther King Dr., Cincinnati, OH 45268. Under an Interagency Agreement with EPA and the Department of Energy, the Oak Ridge Institute for Science and Education (ORISE) is organizing, convening, and conducting the peer-review panel meeting. To attend the meeting, register by February 5 by calling Ms. Rachel Smith, ORISE, PO Box 117, MS 17, Oak Ridge, TN 37831-0117; at 865-241-6428 or by facsimile at 865-241-3168. She may also be reached via e-mail at Interested parties may also register on-line at:​dichlorobenzenereview. Space is limited, and reservations will be accepted on a first-come, first-served basis. Start Printed Page 4515

The document is available primarily on the NCEA web site at​ncea under the What's New and Publications menus. A limited number of paper copies are available by contacting the IRIS Hotline at 202-566-1676; facsimile: 202-566-1749. If you are requesting a paper copy, please provide your name, mailing address, and the document title and number, “Draft Toxicological Review of Dichlorobenzenes and IRIS Summary for 1,2-DCB, 1,3-DCB, and 1,4-DCB” (NCEA-S-1618). Copies are not available from ORISE. Comments may be submitted electronically, by mail, by facsimile, or by hand delivery/courier. Please follow the detailed instructions as provided in the SUPPLEMENTARY INFORMATION section.

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Questions regarding registration and logistics should be directed to Ms. Rachel Smith, ORISE, PO Box 117, MS 17, Oak Ridge, TN 37831-0117; telephone: 865-241-6428; facsimile at 865-241-3168. She may also be reached via e-mail at

If you have questions about the document, contact Chandrika Moudgal, National Center for Environmental Assessment, U.S. EPA, 26 W. Martin Luther King Dr., Cincinnati, OH 45268; phone: 513-569-7078; facsimile: 513-569-7475; email:

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I. Information on the Document

The draft report is a reassessment of the chronic health effects of dichlorobenzenes which were first entered into the IRIS data base in 1989 (1,2-DCB), 1990 (1,3-DCB), and 1994(1,4-DCB). The report provides the scientific basis for deriving or not deriving an oral reference dose (RfD) and inhalation reference concentration (RfC) for the noncancer health risk from exposure to each of the three DCB isomers. A cancer assessment for each is also included in the draft report.

IRIS is a data base that contains scientific Agency consensus positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to specific chemical substances found in the environment. The data base (available on the internet at​iris) contains qualitative and quantitative health effects information for more than 500 chemical substances that may be used to support the first two steps (hazard identification and dose-response evaluation) of the risk assessment process. When supported by available data, the data base provides RfDs and RfCs for chronic health effects, and oral slope factors and inhalation unit risks for carcinogenic effects. Combined with specific exposure information, government and private entities use IRIS to help characterize public health risks of chemical substances in a site-specific situation and thereby support risk management decisions designed to protect public health.

Dichlorobenzenes (CAS Nos. 95-50-1, 541-73-1, and 106-46-7) are produced in an isomeric mixture from the reaction of liquid benzene with chlorine gas in the presence of a catalyst at moderate temperature and atmospheric pressure. Individual isomers of Dichlorobenzene are used primarily as reactants in chemical synthesis, as process solvents, and as formulation solvents. 1,2-Dichlorobenzene is used in the production of 3,4-dichloroaniline, a base material for herbicides; as a solvent for waxes, gums, resins, tars, rubbers, oils, and asphalts; as an insecticide for termites and locust borers; as a degreasing agent for metals, leather, paper, dry-cleaning, bricks, upholstery, and wool; as an ingredient in metal polishes; in motor oil additive formulations; and in paints. 1,3-Dichlorobenzene is used in the production of herbicides, insecticides, pharmaceuticals, and dyes. 1,4-Dichlorobenzene is used as an air freshener, as a moth repellent in moth balls or crystals, and in other pesticide applications. 1,4-Dichlorobenzene is also used in the manufacture of 2,5-dichloroaniline and pharmaceuticals, polyphenylene sulfide resins, and in the control of mildew.

II. How To Submit Technical Comments

EPA has established an official public docket for this action under Docket ID No. ORD-2004-0002. The official public docket consists of the document referenced in this notice and a list of charge questions that have been submitted to the external peer reviewers. Both documents are available on the Internet at​edocket/​. Once in the system, select “search,” then key in the appropriate docket identification number.

Submit your comments, identified by docket ID number ORD-2004-0002, online at​edocket (EPA's preferred method); by e-mail to; by mail to EPA Docket Center, U.S. Environmental Protection Agency (mail code 2822T), 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; or by hand delivery or courier to EPA Docket Center, EPA West, Room B102, 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 Wordperfect or ASCII file, avoiding the use of special characters and any form of encryption.

EPA's policy is that public comments, 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 comment contains copyrighted material, confidential business information (CBI), or other information whose disclosure is restricted by statute.

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Dated: January 23, 2004.

Peter W. Preuss,

Director, National Center for Environmental Assessment.

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[FR Doc. 04-1973 Filed 1-29-04; 8:45 am]