Despite our broad coverage of the ISRI Commodity Roundtable conference held in Chicago a couple of weeks ago, (we covered various scrap markets as well as copper trends, stainless and nickel trends and aluminum trends) we just had to “save the best for last. The single most interesting and for that matter, most provocative comment that came out of that conference came from a panelist on the nickel and stainless steel round table. The comment involved the term “Radiation Hormesis. (Don’t worry we’re not capable of going technical on this) Radiation Hormesis reminds us of an old adage that our mothers used to say, “too much of something is not good for you but a little can’t hurt. One of the panelists at the ISRI conference pointed out that vitamins contain Selenium (toxic at larger doses) or two aspirins are fine but 20 might be problematic. So the analogy to radiation goes like this – little bits of it may be beneficial to your health.
But LNT better known as Linear No Threshold theory serves as the governing policy on the subject of radiation in the US. It is commonly stated that “any radiation dose, no matter how small, can cause cancer, as described by Professor Emeritus of Physics at the University of Pittsburgh, Bernard Cohen, in his paper, “The Linear No-Threshold Theory of Radiation Carcinogenesis Should Be Rejected. We had a chance to speak with Dr. Cohen and in subsequent research discovered this rather outrageous note from a Wikipedia entry on Dr. Cohen, “When Ralph Nader described plutonium as “the most toxic substance known to mankind“, Cohen, then a tenured professor, offered to consume on camera as much plutonium oxide as Nader could consume of caffeine, the stimulant found in coffee and other beverages, which in its pure form has an oral (LD50) of 192Ã‚Â milligrams per kilogram in rats.
LNT theory holds that “that the damage caused by ionizing radiation is directly proportional to the dose at all dose levels. Yet many research organizations and professional associations have rejected this theory and instead, “have come to regard risk estimates in the low-dose region based on LNT as exaggerated or completely negligible. In fact, Cohen’s research paper actually shows quite the opposite that low does of radiation may in fact be beneficial to reducing the rate of cancers. Organizations such as the Health Physics Society, the French Academy of Medicine and the French Academy of Sciences (Aurengo et al 2005) strongly condemned the use of LNT along with the American Nuclear Society. In addition, the U.S, National Council on Radiation Protection and Measurements (NCRP) stated in NCRP Publication No. 121 (NCRP 1995),Ã‚Â “Few experimental studies and essentially no human data can be said to prove or even provide direct support for the [LNT] concept, and in NCRP Publication No.136 (NCRP-2001) stated, “It is important to note that the rates of cancer in most populations exposed to low level radiation have not been found to be detectably increased, and in most cases the rates appear to be decreased.
Ironically, the CDC conducted a study back in 1991 to analyze workers in eight US Navy shipyards that service nuclear-propelled ships (Matanoski 1991). The study analyzed “28,000 exposed workers and “33,000 age- and job-matched controls. The not so shocking finding – according to Cohen’s paper referenced above, “the cancer mortality rate for the exposed was only 85% of that for the unexposed, a difference of nearly two standard deviations. Hiring procedures, medical surveillance, job type, and other factors were the same for both groups; the study was specifically designed to eliminate the “healthy worker effect, which is often used to explain such results. Cohen’s paper cites over half a dozen additional examples of large studies, conducted globally demonstrating that LNT fails to explain the often [positive] benefits of low dose radiation.
In our discussion with Cohen, he mentioned he conducted a study examining radon levels in homes. He specifically measured radon levels in 350,000 houses in the US. From this and other measurements he concluded that counties with high radon levels have lower cancer rates than counties with lower radon levels. He has had this data for 15 years.
So let’s bring this discussion back to our metal scrap supply chains. If the US’s nuclear disposal policy includes burial of any/all materials on the basis of governing LNT radiation policies and the US has 440 nuclear power plants and two thirds of them use pressurized water reactors that in turn rely upon corrosion resistant high strength nickel alloys along with all of the other metals including hundreds of thousands of tons of structural and reinforcing steel, rolled forgings, etc (note we are not discussing spent nuclear fuel rods but rather the metals used to build a nuclear power plant) depending upon how you look at it, we could avail ourselves of enormous non-ferrous and ferrous metal scrap.
Finally, according to Cohen, “In a worldwide poll conducted by the principal on-line discussion group of radiation protection professionals (RADSAFE), the vote was 118 to 12 against LNT, one has to wonder whether the US has erred on the wrong side of this policy debate. But in a world where supply shortages loom large for many base metals and even steel (not to mention rare earth metals) isn’t it time that we at least put LNT to an open public policy debate?