Wood Dust, Talc, Estrogens, And Nickel Alloys Among Substances Being Reviewed For Inclusion In Report On Carcinogens

The meeting is open to the public. Other substances to be reviewed include broad spectrum ultraviolet light, as well as UVA, UVB, and UVC, the flavoring agent methyleugenol, metallic nickel and nickel alloys, trichloroethylene and two pharmaceutical agents long known to have medical benefits, but also with recognized risks for causing cancer.

The final version of this tenth report will be prepared by the National Toxicology Program headquartered at the National Institute of Environmental Health Sciences, one of the National Institutes of Health, for the Secretary of Health and Human Services. As in the past, the next, or tenth, report will also list the regulations or restrictions that apply to the various substances. The reports are mandated by Congress to help the public, as well as Congress, determine if substances with a potential risk of causing cancer are properly regulated. The December advisory review will be by a subcommittee of the NTP Board of Scientific Counselors.

The two medical products to be considered are chloramphenicol, which is an antibiotic in limited use, and steroidal estrogens, which have been used extensively as post-menopausal therapy and in oral contraceptives for women. The data on these and the other substances have already been reviewed by a panel of NIEHS/NTP scientists and a panel of government scientists from many agencies.

Scientists and members of the public can submit material or register to speak at the Dec. 13- 15 meeting by contacting the NTP Board Executive Secretary Mary S. Wolfe, Ph.D., NIEHS, Box 12233, A3-07, Research Triangle Park, NC 27709, e-mailing wolfe@niehs.nih.gov or telephoning (919) 541-0295. An official notice on the meeting begins on page 61352 of the Federal Register, Volume 65, Number 201; updated information is provided on page 75726 of the Federal Register, volume 65, Number 233.

The possible listings are as follows:– Wood Dust, proposed for listing in the category of "known to be a human carcinogen," is associated with increases in cancer of the nasal cavities and paranasal sinuses largely in workers exposed during furniture and cabinet manufacture. An estimated two million people worldwide are routinely exposed to wood dust occupationally.

–Talc in some geological settings contains asbestiform fibers, and workers exposed in some talc mining and milling operations have shown increases in tumors typically associated with exposure to asbestos. This talc, containing the asbestiform fibers, has been proposed for listing under the category, "known to be a human carcinogen." Talc that does not contain asbestiform fibers has been proposed for the listing of "reasonably anticipated to be a human carcinogen." Talcum powder use in feminine hygiene has been associated with ovarian cancer.

– Trichloroethylene (TCE) has been proposed for listing as "known to be a human carcinogen," based in large part on accumulating evidence of liver and kidney cancers in humans exposed to TCE. The solvent is used mainly as a degreaser for metal parts, in vapor or cold degreasing operations for furniture and fixtures, fabricated metal products, electrical and electronic equipment, transport equipment, and miscellaneous manufacturing.

– Steroidal estrogens, which occur naturally in women and to a degree also in men, also have important medical uses as estrogen replacement therapies and for birth control. Their use has long been associated with a somewhat elevated risk of uterine endometrial and breast cancers. Steroidal estrogens have been proposed for listing in the "known" category.

– Broad spectrum ultraviolet radiation – whether from the sun or from lamps and sunbeds –is being reviewed for listing in the 10th Report in the category "known to be a human carcinogen" based on associations with skin cancer, including sometimes fatal malignant melanomas. However, there is less information about the separate wavelengths of ultraviolet radiation so each is separately proposed for listing as "reasonably anticipated to be a human carcinogen."

– Chloramphenicol, an antibiotic, was found to be effective against typhus in 1948 and became one of the first antibiotics in large-scale production. However, by 1950 it was known to sometimes cause potentially fatal aplastic anemia, so it rapidly fell from favor. It is now used in the United States only for serious infections such as meningitis and typhoid fever where other antibiotics are either ineffective or contraindicated. Limited studies in humans have associated the drug with leukemia. It is proposed for listing as "reasonably anticipated to be a human carcinogen."

– Methyleugenol, a flavoring agent that occurs naturally and is also made synthetically, has been found to be a carcinogen in experimental animal studies and is proposed to be listed in the category, "reasonably anticipated to be a human carcinogen." It is used in jellies, baked goods, nonalcoholic beverages, chewing gum, candy and ice cream, and as a fragrance in perfumes, lotions, detergents and soaps. Methyleugenol is a naturally occurring substance present in pimento, basil, hyacinth, citronella, anise, nutmeg, mace, cinnamon leaves, pixuri seeds, laurel fruits and leaves, blackberry essence, bananas, black pepper and bilberries.

– Metallic nickel and nickel alloys, have each been proposed to be listed as "reasonably anticipated to be a human carcinogen." Nickel and nickel compounds were reviewed for listing in the ninth Report on Carcinogens, but the listing was deferred until metallic nickel and nickel alloys could undergo additional specific review.

Staff papers on the proposals can be read at http://roc.niehs.nih.gov/rocpublic