|
Barbara,
Of course at higher doses (>10
rem/a), the doserate is an important determinant of health effects.
However, for any dose at or below
de minimis level, the dose rate should be of no
significance.
IMHO, a dose 0.5 rem is de minimis
so that it should not matter whether such a dose is received over a period
of one year, or one second.
----- Original Message -----
Sent: Monday, August 12, 2002 10:43
PM
Subject: Re: What to do ? ? ?
In a message dated
08/11/2002 8:55:58 PM Pacific Daylight Time, lists@richardhess.com writes:
If I recall correctly 0.5 REM/year is the guideline for the
average
population??? What would you consider a guideline for worrying?
Getting all
of that in a week? One day? 10x that in a week? Rough ideas
would be helpful.
The current NRC
regulation, which is a matter of compatibility for all Agreement States
(meaning it is basically a national standard for commercial uses of Atomic
Energy Act material) is 100 millirem per year to any member of the public from
licensed operations, with a few exceptions here and there. As has
previously been pointed out, a fetus borne by an occupational worker is
allowed up to 500 millirem over the gestation period (if the woman elects to
declare her pregnancy). Family members, roommates, co-workers, etc. of
certain nuclear medicine patients (most likely iodine-131 therapy patients
treated for hyperthyroidism or thyroid cancer) are allowed to receive up to
500 millirem per year as well. Occupational wokers may routinely receive
up to 5,000 millirem per year and up to 10,000 millirem per year under certain
pre-planned circumstances.
The June 2001 GAO report, on the continued
disagreement between the NRC and EPA, states that below 5,000 to 10,000
millirem there is no evidence of health effects - harmful or beneficial.
I know members of this list may refute that, because there actually is
some legitimate evidence of beneficial effects, but it's still not
"mainstream" science in the common sense of the phrase.
The natural
variation in background radiation in the U.S. covers about an order of
magnitude - i.e., from about 100 millirem per year to 1,000 millirem per year
(in the higher elevations of the Rockies). The Denver area has some of
the highest background levels in the country, yet Denver County has the third
lowest cancer rate in the country.
There are a number of things to
keep in mind when considering radiation:
1. It is probably one
of the most well-studied and understood of all the carcinogens. (Try
running a google search on "risk" and "fatal cancer" and see how many sites
come up on radiation versus the myriad of other known carcinogens).
2.
Compared to other known carcinogens, we have an amazing capability to
detect its presence. The development of instrumentation devoted to
finding every last radioactive atom in this world is far beyond the
development of equipment designed to detect most other hazardous substances,
making it an easier target for regulation (and, subsequently public fear) than
other substances.
3. It has the unique status of being
associated with the dreaded atomic bomb. Most lay-persons in my
generation will, in the back of their minds, always connect radioactivity to
some extent with the nightmare of the atomic bomb, as it was presented to us
in our formative years. There is a psychological component to the fear
of radiation (as discussed here at length) that may take a formidable amount
of education to overcome.
Those are my thoughts on the matter - my
personal thoughts, and not the thoughts of anyone I work for, or have worked
for, or have ever written a critical editorial about.
Barbara
|