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From: denbeste@spdcc.com (Steven Den Beste)
Newsgroups: sci.med,sci.med.aids,sci.physics,soc.motss,sci.med.physics,sci.energy
Subject: Re: question about ultroviolet lamps and germs
Keywords: ultroviolet light, aids, germs, ideas
Message-ID: <1990Dec11.014351.27688@cs.ucla.edu>
Date: 10 Dec 90 23:20:41 GMT
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In article <1990Dec10.214104.21682@cs.ucla.edu> !maa@ssc-vax (Mark A Allyn) writes:
#Once upon a time when I went to kindergarten many years ago, I remember a 
#special lamp that was mounted high on the wall. It put out a strange deep
#blue light and it was aimed up at the cieling. The teacher kept warning us
#not to climb up and look down into it because it would hurt us. She said it
#was there to kill bacteria and viruses. I vaguely remember her saying it was
#a special ultroviolot light. The bulb was mounted inside a fixture that only
#allowed the beam to go up at the cieling so I could not see what kind of bulb
#it was. My curiousity has been perked by it, espeically now in the the age of
#aids. I have some wacky ideas about this that I want to throw out to you 
#folks.

They used to sell infrared lamps and claim that they would make you healthy,
too. I suspect that your teacher was a crackpot.

#
#First of all, does anyone out there in sci.physics land or sci.med land know
#how an ultroviolot light kills viruses and bacteria? Is it the same effect that
#causes eye damage to humans? Can someone give me a kind of nutshell 
#explanation of the physics/medical/photochemical whatever stuff involved? I
#am an electrical/computer science weenie and can understand some physical/
#chemical/medical jargon. Thanks. What kind of ultroviolot light is involved?
#Near visable or deep ultroviolot?? Is it the same ultroviolot that is used 
#for 'black' lights in bars and theater? For that matter, why is it safe to
#look at the 'black' lights and not at those ultroviolot lights designed to
#kill germs?

First off, it is much more likely to affect bacteria than virii.

Remember Einstein? He got a Nobel prize, but not for the theories of Reltivity.
Instead, he got it for something called the "photo-electric effect". What it
amounts to is that if an energetic photon strikes matter, it can energize an
electron, perhaps enoug to break it free. That's how TV cameras work.

Well, if the electron it strikes is one which is helping to hold an organic
molecule together, the structure of the molecule can be changed, or even
disrupted entirely. That enzyme no longer mediates the reaction it was supposed
to, and maybe the fragments now do something else that is harmful.
The likelyhood of a given photon doing this is a function of its energy, and
the lower threshold of danger is somewhere in the ultraviolet region. "Soft"
UV, that is, within the first few octaves above the visible range, is still
too weak to have much effect. But in the "hard" UV range, there is truly a
problem.

Doing this to an enzyme is not usually a problem: There are LOTS of enzymes,
and the loss of one particular molecule probably won't affect things much.
Where it gets REALLY dangerous is during cell division. While the DNA is being
replicated, a tricky operation at the best of times, if a hot photon hits just
right it can cause a transcription error - sometimes called a mutation.
One way this is really bad is that it can cause the resulting cell to be
cancerous.

Your skin can tolerate a certain amount of UV because it is protected by a dead
layer - the first few thousand cells in depth are constantly growing from below
and sloughed off from above. Since they're dead anyway, no reproduction is
going on or anything else interesting, so the effects of the photons doesn't
cause important damage. But your eyes are a different story. Not only is the
surface of your retina alive, but your eyes are set up so they will, to some
extent, focus the UV and concentrate it. Not good...

What has all of this got to do with a virus? Not a whole lot. Not only is a
virus thousands of times smaller than a bacteria, but it isn't really alive.
No DNA or RNA transcription takes place in a virus. It isn't a machine, it's
a floppy disk containing a program to take over a machine. That program is
its DNA or RNA. Only when it invades an appropriate cell and releases its
DNA or RNA does it begin to act alive, since it takes over the reproduction
mechanisms of that cell and forces it to create new virii.

Out in the open, sitting idly, a virus is a remarkably hard thing to damage.
There isn't any way that a small amount of UV would do it. Forget about it as
a form of anti-AIDS protection.

#
#Next question - can these concept be helpfull in the arena of aids? 
#For example, make a special ultroviolot fixture that is 
#encased in a dildo and insert it
#into a vagina or anus just before sex, turn on the ultroviolot light, and kill
#the aids virus and then go ahead and have sex? Or better still, have a
#fixture shaped like a cylinder with ultroviolot light bulbs around it (shielded
#from your eyes) and stick you penis into it for a while before having sex?
#Is this something that is really wacky or does it have any merit? 

The problem with the UV dildo and a vagina is that the dose of UV necessary to
destroy bacteria and virii would also cause significant damage to the vagina.
It's gonna hurt like a sonofabitch...

Anyway, the problem is that the secretions in a vagina are continuously created
during intercourse, mostly from blood plasma. Even if you could sterilize
it before you began, the later secretions are going to be just as
dangerous. The situation with the anus is similiar: The problem there is that
the tissue breaks and blood is released. The blood wasn't present when you
"sterilized", but it's just as dangerous as if you hadn't bothered.

#
#Final question - what would happen if units of donated blood are subject to
#bombardment of ultroviolot energy? Would the aids virus be killed? Has any
#one out there allready thaught of this??

The real difficulty with AIDS is that it is what is known as a "retrovirus".
What this means is that it doesn't just inject its RNA into the cell and take
over, it does something much more insidious. Its RNA creates an enzyme called
"reverse transcriptase", which takes its RNA and transcribes it into the
central DNA of the cell. It doesn't take over immediately. Instead, it lets the
T4 cell divide a few thousand times and THEN it takes over. Instead of having
a single cell making little HIV's, it has hundreds or thousands of them, all
from one infection event.
AIDS-infected blood doesn't have that great an amount of HIV as such; what it
has is lots of infected T4 cells, which are part of the normal blood. Any level
of UV bombardment capable of destroying all the T4 cells would render the rest
of the blood useless.