Re: Radiation Hormesis

[RuthWeiner@AOL.COM]

In a message dated 1/19/2004 12:24:06 PM Eastern Standard Time, "Joan Stovall" <joans@PCEZ.COM> writes:



>I am convinced there is a hormesis effect.

>

>Some evidence:

>

>1.  The Health Physics Journal ran an issue on Hormesis in the late 1980's.

>There was a study on cancer rates in india.  The Kerala province has the

>highest background levels in India, but has the lower cancer rates than the

>rest of India.  India is a developing nation, which means there are less

>industrial pollutants to confound the issue.



This is not particularly good evidence for hormesis.   Smoking, agricultural chemicals and other agricultural practices, and diet confound the issue.  Moreover, there is heavy industry and thermally produced electricity in India.  Finally, lifespan is a major confounder -- the best predictor of cancer is age. Using this example to demonstrate hormesis would require comparing two populations the only difference between which is background radioactivity.



>

>2.  Ramsar, Iran has very high background radiation levels, but does not

>have any elevation of cancer rates.



Elevation over what?  See answer above.

>

>3.  Principles of toxicology.  Paracelsus elucidated this very well with his

>statement, "The dose makes the poison."  Examples:

>    a.  Vitamin A is necessary for life, but too much is

>potentially lethal.

>    b.  Arsenic in drinking water.  New Mexico has  what         are perhaps

>the highest average drinking water                 concentrations of arsenic

>for the nation (20 to 40             parts per billion).  However, New

>Mexico has lower         cancer incidence rates than the rest of the

>country.



This argues for a threshold, not for hormesis.  All you are saying about the arsenic concentration in New Mexico is that it is below some threshold of effect.  Besides, INGESTED arsenic doesn't cause cancer anyway --that's INHALED arsenic, of which New Mexico has none since Phelps Dodge closed. It also depends on WHERE in a state one lives. the Pecos doesn't have the arsenic concentration of the Rio Grande. Northern new mexico, including Albuquerque and Santa Fe, never had much airborne arsenic. (we have a lot of heavy smokers and drunks, though)   Besides, New Mexico has as mobile a population as anywhere else in the U. S. According to the Census Bureau, people in the U. S. move on the average every three years.  I have lived in Maryland, Illinois, Florida, Washington State, DC, and New Mexico, for approximately equal lengths of time, so my cancer incidence or lack thereof would prove nothing at all.  



>    c.  Chromium compounds in the diet.  High intake of             chromium

>(hexavalent in particular) is linked to                 cancer.  However,

>trace levels of chromium                     compounds are a necessary

>nutrient.  Chromium in         the diet is linked to regulation of

>metabolism.                  Thailand has a greater level of chromium in the

>diet,         compared to other countries, but the incidence of

>diabetes is less.



Since when is hexavalent chromium linked to diabetes, and what is the mechanism?  "Regulation of metabolism" involves a lot more hormones than pancreatic insulin.



The toxicity of large quantities of a necessary nutrient is not related to hormesis either,  has been known for a long time, and not just for synthetic chemical compounds.  Vitamin D toxicity is well-known and well-understood.





-- 

Ruth F. Weiner

ruthweiner@aol.com

505-856-5011

(o)505-284-8406

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