Re: Radiation Hormesis

["Joan Stovall" <joans@PCEZ.COM>]

I did not mean hexavlent chromium was in the diet in Thailand, but other

chromium compounds are in someway linked with the metabolism of

carbohydrates, but I am not sure of the mechanism.



I doubt we will ever be able to prove that hormesis does occur.  However,

the threshold effect may be much easier to prove.  But, it will require very

large samples.



----- Original Message ----- 

From: <RuthWeiner@aol.com>

To: ""Joan Stovall"" <joans@pcez.com>; ""Karl Ellison""

<ellison1@localnet.com>; <radsafe-digest@list.vanderbilt.edu>

Sent: Monday, January 19, 2004 11:52 AM

Subject: Re: Radiation Hormesis





> 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. Weinerruthweiner@aol.com505-856-5011(o)505-284-8406

>

>





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