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John,
I don't see where
sensory perception of a given physical or chemical agent needs
to be related in any way to its potential harmful or beneficial
effects. If that were the case, people would not drink alcohol, or
sunbath, or exercise. What feels good is not necessarily good for you,
nor is what feels bad necessarily bad for you.
Perhaps we are
just acclimated to background radiation levels and if somehow could
be plunged into a radiation free environment would experience a sensory
deprivation of some sort.
Incidentally, the
tingling sensations I thought I had experienced in fields of ~0.1-
0.5 mSv/hr did not seem to be unpleasant. Hormesis,
maybe??? In any
case, the question posed is: Can people sense ionizing
radiation, or was I just imagining it? I really do not intend any devious implications by this
question. Just curious,that's
all....
Jerry
----- Original Message -----
From: Jacobus, John (OD/ORS) <jacobusj@ors.od.nih.gov>
Sent: Friday, May 31, 2002 10:15 AM
Subject: RE: Sensory Perception of
Radiation Thank you for passing this along. I take it from Jim's quotation (source unknown) that in the range of 1 mSv to 280 mSv background levels are inconsequential. I assume that implies radiation as no essential energy or having a hormetic effect quality that we need, or else we would have evolved sense organs for it. I am curious as to the statement that radiation levels of 1 mSv to 280 mSv per year compares to a temperature range of 50K. Where does that come from? Obviously temperature differences are more important to life than radiation at background levels. Have a good weekend. -- John John Jacobus, MS Certified Health Physicist 3050 Traymore Lane Bowie, MD 20715-2024 E-mail: jenday1@email.msn.com (H) -----Original Message----- From: Jerry Cohen [mailto:jjcohen@PRODIGY.NET] Sent: Friday, May 31, 2002 12:09 PM To: radsafe@list.vanderbilt.edu; rad-sci-l@ans.ep.wisc.edu Subject: Re: Sensory Perception of Radiation . . . ---------------------------------------------------------------------------- "Perhaps we humans lack a specific organ for sensing ionizing radiation simply because we do not need one. Our bodies' defense mechanism provides ample protection over the whole range of natural radiation levels-that is, from below 1 mSv to above 280 mSv per year.3,4 That range is much greater than the range of temperatures-about 50K-that humans are normally exposed to. Increasing the water temperature in your bath tub by only 80 K, from a pleasant level of 293 K to boiling point at 373 K (that is, by a factor of only 1.3), or decreasing it below freezing point (that is, by a factor of 1.07), would eventually kill you. "Because such lethal high or low temperatures are often found in the biosphere, the evolutionary development of an organ that can sense heat and cold has been essential for survival. Organs of smell and taste have been even more vital as defenses against dangerously toxic or infected food. But a lethal dose of ionizing radiation delivered in one hour-which for an individual human is 3000 to 5000 mSv-is a factor of 10 million higher than the average natural radiation dose that one would receive over the same time period (0.00027 mSv). Compared with other noxious agents, ionizing radiation is rather feeble. Nature seems to have provided living organisms with an enormous safety margin for natural levels of ionizing radiation-and also, adventitiously, for man-made radiation from controlled, peacetime sources. "In short, conditions in which levels of ionizing radiation could be noxious do not normally occur in the bioúsphere, so no radiation-sensing organ has been needed in humans and none has evolved." Regards, Jim ----- Original Message ----- From: "Jim Muckerheide" <jmuckerheide@cnts.wpi.edu> To: <rad-sci-l@ans.ep.wisc.edu> Sent: Thursday, May 30, 2002 3:28 PM Subject: FW: [rad-sci-l] 'Voting with feet' for/against Low vs. Hi Dose Rad! :-) . . . ************************************************************************ You are currently subscribed to the Radsafe mailing list. To unsubscribe, send an e-mail to Majordomo@list.vanderbilt.edu Put the text "unsubscribe radsafe" (no quote marks) in the body of the e-mail, with no subject line. You can view the Radsafe archives at http://www.vanderbilt.edu/radsafe/ |