Reply #70: from a link in the link you cite [View All]

[treepig]

Laboratory tests have shown that formaldehyde can cause nasal cancers in rats exposed to a concentration of 14.3 ppm of formaldehyde for 24 months. Mice exposed to the same concentration of formaldehyde did not develop a statistically significant increase in cancers. In humans, numerous epidemiological (causes of death) studies have been done on various groups of workers exposed to formaldehyde. These have included morticians, garment workers, wood workers, foundry workers, painters, and barbers, among others. To date, there do not appear to have been any statistically significant increases in cancers at any site in humans. Many of these studies have suffered from lack of exposure and smoking history data. Due to cancers found in animal studies, and the limited and controversial human epidemiological studies, both the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) consider formaldehyde to be a possible human carcinogen, and regulate it accordingly.


http://www.meridianeng.com/formalde.html


and to the point of there being no known threshold doesn't mean that it doesnt' exist. in fact, there are likely doses at which formaldehyde (and most other toxins, such as water which i've explained elsehwere is deadly if ingested at a rate greater than 17 mL/min over a period of several hours) are actually beneficial:

The Delaney cancer clause states that an agent should be considered carcinogenic '...if it is found, after tests which are appropriate for the evaluation of the safety of food additives, to induce cancer in man or animal...' The limits of 'tests which are appropriate' were repeatedly exceeded in overzealous efforts to find dietary and environmental carcinogens. The flawed concept remains: any agent which is carcinogenic at high doses is considered to be carcinogenic in minute doses. Interpolation of results obtained with large doses to zero is much less expensive than performing difficult experiments with small or minute doses. Acceptance of small amounts of some proven carcinogens in our food followed discovery of their existence in common foods, e.g., cholesterol, formaldehyde, or nitrostamines, or conviction that it was an essential nutrient, e.g., selenium. Selenium. long known to be poisonous and now accepted as essential, is carcinogenic in high doses and is anticarcinogenic in low doses. (Frost 1972)

"The phrase '...tests which are appropriate...' was indirectly acknowledged by the U.S. Food and Drug Administration (FDA) to the Associated Press (Philadelphia Inquirer May 17, 1989, p.7A) when they rejected the carcinogenicity of bladder implanted chemicals as an index of ingested food additives. Cyclamates were approved 20 years after appropriate tests had been submitted. This precedent should waken both liberal and conservative groups to the possibility that high and low doses of the same agent produce dramatically opposite results. This was inadvertently accepted when FDA beefed up the control group in tests showing red dye #2 was carcinogenic: the mice which had been fed small amounts of the dye, found to be carcinogenic in large doses, were added to the control group to provide increased numbers for better statistics.