A big study published in July showed that hormone replacement therapy
increases the risk of several kinds of cancer, including breast cancer, although it seems to lower the risk of colon cancer. It also raises
the risk of heart disease.
The report also lists wood dust as a "known human carcinogen." The report,
part of the National Toxicology Program's biennial report on cancer-causing
agents, says unprotected workers in sawmills, furniture factories and similar
places have a higher risk of cancers of the nasal cavities and sinuses.
And it lists broad-spectrum ultraviolet light, both naturally produced by the
sun and the light made by tanning beds and lamps, as a known cause of cancer in
people.
The various separate kinds of UV light, such as UVA, UVB and UVC, are listed
as probable carcinogens because it is not clear whether each one on its own
alone could cause cancer.
"This and 15 other new listings bring the total of substances in the report,
'known' or 'reasonably anticipated' to pose a cancer risk, to 228," the
Department of Health and Human Services said in a statement.
The NTP, part of the National Institute of Environmental Health Sciences, one
of the National Institutes of Health, updates its list of known and suspected cancer-causing agents after
lengthy study and scientific reviews by three expert panels of government and
non-government scientists.
Also new to the list are nickel compounds and beryllium and its compounds
commonly used in industry. Beryllium was previously listed as "reasonably
anticipated to be a human carcinogen."
"About 800,000 workers are exposed via inhalation of beryllium dust or dermal
(skin) contact with products containing beryllium," the department statement
said.
"Workers with the highest potential for exposure include beryllium miners,
beryllium alloy makers and fabricators, ceramics workers, missile technicians,
nuclear reactor workers, electric and electronic equipment workers, and
jewelers."
Joining the list of reasonable cancer suspects are IQ, or
2-amino-3-methylimidazo(4,5-f)quinoline, which is formed during direct cooking
with high heat of foods such as meat and eggs and which is also found in
cigarette smoke.
