National Toxicology Program (NTP); Report on Carcinogens (RoC); Request for Public Comments on the RoC Expert Panel's Recommendations on Listing Status for Captafol and Ortho-nitrotoluene in the 12th RoC and the Scientific Justifications for the Recommendations

AGENCY:

National Institute of Environmental Health Sciences (NIEHS); National Institutes of Health (NIH).

ACTION:

Request for public comment.

SUMMARY:

The RoC Office invites public comment on the recommendations from an expert panel on listing status for captafol and ortho-nitrotoluene in the 12th RoC and the scientific justification for the recommendations. The recommendation and scientific justification for each candidate substance are available electronically in Part B of the Expert Panel Report http://ntp.niehs.nih.gov/go/29682,, (see Expert Panel Report Part B) or in printed text from the RoC Office (see FOR FURTHER INFORMATION CONTACT below). The RoC Office convened a nine-member expert panel of scientists from the public and private sectors on October 15-16, 2007. The panel was asked (1) to apply the RoC listing criteria to the relevant scientific evidence and make a recommendation regarding listing status (i.e., known to be a human carcinogen, reasonably anticipated to be a human carcinogen, or not to list) for captafol and for ortho-nitrotoluene in the 12th RoC and (2) to provide the scientific justification for the recommendation.

DATES:

The Expert Panel Report (Part B) for captafol and for ortho-nitrotoluene will be available for public comment by March 3, 2008. Written comments should be submitted by April 24, 2008.

ADDRESSES:

Comments should be sent to Dr. Ruth Lunn, RoC Office [NIEHS, P.O. Box 12233, MD EC-14, Research Triangle Park, NC 27709, FAX: (919) 541-0144, or lunn@niehs.nih.gov. Courier address: Report on Carcinogens, 79 T.W. Alexander Drive, Building 4401, Room 3118, Research Triangle Park, NC 27709].

FOR FURTHER INFORMATION CONTACT:

Dr. Ruth Lunn, RoC Office, 919-316-4637 lunn@niehs.nih.gov.

SUPPLEMENTARY INFORMATION:

Background

Captafol and ortho-nitrotoluene are among the candidate substances under review for possible listing in the 12th RoC (see complete list at http://ntp.niehs.nih.gov/go/10091 ). Captafol (CAS RN: 2425-06-1) is a broad-spectrum fungicide that was widely used in the United States prior to the mid 1980s on fruits, vegetables, and other plants, as well as on timber products. In 1999, the U.S. Environmental Protection Agency (EPA) revoked all captafol tolerances except those for onions, potatoes, and tomatoes. In 2006, EPA revoked specific tolerances and tolerance exemptions for captafol, and stakeholders withdrew their support for import tolerances. Although many countries have now banned its use, captafol is still registered in some countries (such as Mexico). The potential exists for past, extensive exposure for U.S. workers producing the chemical, as well as for agricultural workers because of past production and use of millions of pounds of captafol.

Ortho-nitrotoluene (CAS RN: 88-72-2) is used to synthesize agricultural and organic chemicals, explosives, azo and sulfur dyes, and dyes for cotton, wool, silk, leather, and paper. Ortho-nitrotoluene is a high production volume chemical, and its U.S. production was between 10 million and 50 million pounds for every four-year reporting period from 1986 to 2002. Exposure to ortho-nitrotoluene in the United States is primarily a result of occupational exposure during the production and use of this chemical.

As part of the RoC review process (available at http://ntp.niehs.nih.gov/go/15208 ), the NTP announced the availability of the draft background documents for captafol and ortho-nitrotoluene in the Federal Register (72 FR 41755, July 31, 2007), invited public comments on the draft background documents, and announced the captafol and ortho-nitrotoluene expert panel meeting. The RoC Office convened a nine-member expert panel of scientists from the public and private sectors to evaluate these two substances. The expert panel met on October 15-16, 2007, in a public forum at the Sheraton Chapel Hill Hotel in North Carolina. The panel first addressed captafol and then ortho-nitrotoluene in its deliberations. The panel was charged to peer review the draft background document for the candidate substance and then to make a recommendation on its listing status in the 12th RoC and to provide a scientific justification for that recommendation. Details about the meeting, including public comments received and the expert panel reports, are available on the RoC Web site ( http://ntp.niehs.nih.gov/go/29682 ). The expert panel report for each candidate substance contains two parts: Part A contains the peer-review comments on the draft background document and Part B is the recommendation on listing status and its scientific justification. The expert panel recommended that (1) captafol be listed in the 12th RoC as reasonably anticipated to be a human carcinogen and (2) ortho-nitrotoluene be listed in the 12th RoC as reasonably anticipated to be a human carcinogen. The panel's recommendation on listing status and its scientific justification are now being released for public comment.

Next Steps

The RoC Office is in the process of finalizing the background document for each candidate substance based upon the expert panel's peer review comments and the public comments received (72 FR 41755). Persons can register free-of-charge with the NTP listserve ( http://ntp.niehs.nih.gov/go/231 ) to receive notification when the final background documents are posted on the RoC Web site ( http://ntp.niehs.nih.gov/go/10091 ).

As part of the RoC review process, two government groups will also conduct reviews of captafol and ortho-nitrotoluene; these meetings are not open to the public. Upon completion of these reviews, the NTP will (1) draft a substance profile, for captafol and for ortho-nitrotoluene which contains its listing recommendation for the 12th RoC and the scientific information supporting that recommendation; (2) solicit public comment on the draft substance profiles; and (3) convene a meeting of the Board of Scientific Counselors to peer review the draft substance profiles.

Request for Comments

The RoC Office invites written public comments on the expert panel's recommendations on listing status for captafol and ortho-nitrotoluene and the scientific justifications for the recommendations. All comments received will be posted on the RoC Web site. Persons submitting written comments are asked to include their name and contact information (affiliation, mailing address, telephone and facsimile numbers, e-mail, and sponsoring organization, if any) and send them to Dr. Lunn (see ADDRESSES above). The deadline for submission of written comments is April 24, 2008.

Background Information on the RoC

The RoC is a Congressionally mandated document that identifies and discusses agents, substances, mixtures, or exposure circumstances (collectively referred to as “substances”) that may pose a hazard to human health by virtue of their carcinogenicity. The RoC follows a formal, multi-step process for review and evaluation of selected chemicals. Substances are listed in the report as either known or reasonably anticipated human carcinogens. The NTP prepares the RoC on behalf of the Secretary of Health and Human Services. Information about the RoC and the review process are available on its Web site ( http://ntp.niehs.nih.gov/go/roc ) or by contacting Dr. Lunn (see FOR FURTHER INFORMATION CONTACT above).