New List of Carcinogens May Include Viruses

 

Inclusion would be a first for government report

 

By Adam Marcus

HealthScoutNews Reporter

 

MONDAY, July 30 (HealthScoutNews) -- Three viruses are among the list of

nominees for inclusion in the latest list of potential sources of human

cancer.

The 16 nominations for the Eleventh Report on Carcinogens, due out in 2004,

include two strains of hepatitis -- B and C, which have been linked to liver

cancer -- and human papillomavirus (HPV), which is a leading source of

cervical cancer in women. It's the first time viruses have been proposed for

the report, which comes out every two years.

 

The report, which Congress established in the 1970s, initially covered only

well-defined chemicals or chemical mixtures. But a mid-1990s review of the

statute creating the report encouraged cancer researchers to open its

membership to other substances or exposures, says Bill Jameson, who oversees

the document for the National Toxicology Program (NTP), a division of the

National Institute of Environmental Health Sciences. The ninth report, for

example, included exposure to sunlight as a known cause of skin tumors.

 

"The data appears to be very strong that there is an association between

[the proposed viruses] and cancer in man," Jameson says. "I'm sure in the

future there will be others."

 

Most of the items on the latest list were put there by government

researchers, whose review of the scientific literature turned up at least

the potential for concern. They include: cobalt sulfate, a substance used in

ceramics and electroplating; naphthalene, found chiefly in mothballs and

toilet bowl deodorizers; X-ray radiation and neutrons. Exposure to these

atomic particles is typically trivial, but patients undergoing neutron

radiotherapy and possibly also aircraft travelers and crew may be at

increased risk of cancer.

 

Also among the nominees this round are occupational exposure to lead and

lead compounds, such as those churned out by smelting facilities, battery

works, steel welding and even firing ranges. Recent evidence suggests that

exposure to high levels of lead may up the risk of brain, lung, kidney and

other cancers.

 

A private group, the United Auto Workers, has proposed that diethanolamine,

or DEA, make the list. DEA belongs to a group of molecules called

surfactants. These chemicals reduce surface tension of liquids and are used

in a wide range of applications, from detergents and cosmetics to neonatal

intensive care, where they help babies with under-formed lungs breathe. Work

in rodents has shown "clear evidence" that DEA, which the auto industry uses

in metalworking applications, can cause cancer in some mice, the NTP says.

 

Franklin Mirer, the UAW's director of health and safety and a noted

toxicologist, says, "The data available are from the rodent [test]; however,

there is some indication of increased liver toxicity and liver cancer in

humans" from skin exposure to the substance.

 

"Metalworking fluids are at the top of our list of health hazards associated

with work for our membership," says Mirer, adding that "thousands" of union

members are probably exposed to DEA on the job. The chemical "is probably

one of five carcinogens that are routinely found in metalworking fluids. In

this case, it's there as something that can be substituted for, or as an

unwanted contaminant."

 

Jameson says suggestions from non-governmental sources are treated the same

as those coming from within the federal envelope. "When we receive a

nomination from outside the NTP, we take it very seriously and usually go

through the effort of putting together a background document to see all the

relevant information," he says. On the other hand, Jameson adds, the

substances and exposures ultimately reviewed are far fewer than the catalog

of chemicals the public proposes.

 

The list of nominees will now undergo a period of public comment along with

a review by government toxicologists, who will determine the cancer risks,

if any, of each. Those with clear evidence of their harm to humans are

labeled "known" carcinogens, while those with less-certain risks may be

considered "reasonably anticipated" to cause cancer.

 

The initial conclusions will then become part of a draft report, which gets

circulated throughout other federal agencies. A final version is due to

Congress in 2004.

 

What To Do

 

For a complete list of the nominated substances and exposures, visit the

National Institute of Environmental Health Sciences.

http://ntp-server.niehs.nih.gov/htdocs/Liason/RoC11NewNomsFR.html

 

To learn more about the toxicology report, check out the National Toxicology

Program.

http://ntp-server.niehs.nih.gov/NewHomeRoC/AboutRoC.html

 

http://www.healthscout.com/template.asp?page=newsdetail&ap=55&id=500735

 

 

 

"When the way comes to an end, then change - having changed, you pass through."

      I. Ching

 

 Bruce "Doc". Melson

http://www.docmelson.com/

http://www.docmelson.com/MedicsPlace/index.htm