Radiation, Japan, and irresponsible reporting: Part I

17 03 2011

Intensity diagram of the Japan quake. The epicenter of the quake is represented by the black star. (Credit: United States Geological Survey)

While the media continues to sensationalize what is already a “gee-whiz” bewildering topic for most ordinary people on planet Earth – nuclear reactors and radioactivity – the recent run on Potassium-Iodide tablets in the United States and on the Internet betrays just how badly the outlets are throwing gasoline on the raging inferno of ignorance out there when it comes to radiation.

I can only presume this is to attract viewers.

Consider this  the first in a small series of posts that seek to contribute a clarifying voice out into the chaos.  To what end?  Hopefully, by the end of these posts, intrepid reader, you’ll understand why the nuclear reactor disasters are serious, but you’ll also see why they pale in comparison to the biochemical environmental apocalypse taking place in Japan due to everything else the earthquake and tsunami destroyed.

So, first, let’s start at the beginning.   What is radiation?

Let me emphasize – there is nothing magical or supernatural about what we call “radiation” and/or “radioactivity.”  A radioactive atom is an overweight version of a “normal” atom, and it naturally tries to get rid of energy to slim down to normal size.  To do this, it “radiates” energy in the form of intense invisible light (gamma rays) and physical bits of itself (atomic particles) away from itself.  That’s it.

Really, radiation science is a form of chemistry.  It’s equally amazing that chemicals can combust to drive cars, that acids burn, etc.  So, let’s get over the “mysterious” hump right here: Radiation is just the chemistry and phsyics of overweight atoms, and it obeys the same laws of physics as everything else.

Second, and most importantly before we go any farther, is to start to understand the terminology used (and misused) everywhere.  So, there is really only one thing you need to understand to understand how radiation works and how to deal with it, and it is this: There is a difference between “radiation” and “contamination.”  A huge difference.  -And to confuse the two is to commit a gargantuan error.

Radiation refers to the invisible light and particles that the overweight (i.e., radioactive) atoms are sluffing off.  Experiencing radiation is like basking in the glow of a heat lamp.  You can get burned/damaged by it, but it won’t come off on you.

Radioactive Material is (unsurprisingly and simply) the name given to material that emits radiation.

Contamination, on the other hand, is when radioactive material is actually moved, blown, spilled, etc., someplace that you don’t want it.  If you get covered with dust that is radioactive material (see above), then you have been contaminated.  This is what you need to wash off, make sure you don’t inhale, etc.

So, what’s the take-home?

  • You can stand next to radiation without fear of getting contaminated.  There’s nothing mysterious in the air – it’s no different than how you can walk away from an x-ray machine without fear of tracking some of the x-rays home with you.
  • Radioactive material emits radiation, but it won’t result in contamination if the material is tidy, safely contained, and solid.

You can see now how if you say, “There’s radioactive material over there!” it means something very different than, “There’s radiation over there!” and very different still than, “There’s radioactive contamination over there!”

The first sentence could simply refer to completely safe-to-handle medical sources or other, completely expected sources of radiation.

The second sentence is very ambiguous and refers to the presence of the invisible light (gamma/x-rays) or particles, meaning that radioactive material must be nearby – but it may still be completely expected.

The third sentence is the only one of the three that implies anything is wrong.  Contamination means radioactive material has been deposited somewhere you don’t want it.  So – by mixing these up, which often happens in the news, the conversation can’t even sensibly go any farther.

To be continued…

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Space radiation has Astronauts seeing stars

2 01 2011

View of Earth at night from the International Space Station. The thin atmosphere layer visible acts as a natural radiation shield. (Credit: NASA)

There are many astronauts experiences that are well understood.

Everyone knows about “weightlessness,” or floating in a microgravity environment, (which is actually perpetual free-fall around the Earth, but that’s a technicality for another post.)

Everyone has heard about the problem of space sickness that hits some astronauts and not others.   Disruptions in our sense of orientation (i.e., up and down,) are likely to blame.

However, what many do not know about are the strange “flashes” of light astronauts see while in space and what it might mean for their future heath.  With commercial space travel on the horizon and space tourists and commercial astronauts lining up to take part, the realities of space travel must be explored and disclosed.

The Earth’s atmosphere normally acts as a shielding layer, protecting the surface from cosmic and solar radiation.  However, when we travel beyond the atmosphere, (i.e., space,) we increase our exposure to such radiation.  In truth, these “flashes” reported by astronauts are actually electrochemical reactions occurring in astronauts’ eyes as a result of high-energy radiation striking their retinas.  A radiated particle passes through the lens of the eye, strikes the retina, and fakes out the optic nerve, which in turn interprets the signal as light.

So, aside from being strange, what are the potential effects of these flashes?

There appears to be a relationship between this radiation exposure and later development of cataracts, a disease characterized by a clouding of the lens of the eye.  According to a 2001 study, a total of 39 astronauts have developed cataracts later in life, and 36 of them flew on high-radiation missions, such as those to the Moon.

Scientists are currently working on nailing down the genetic link between radiation exposure and cataracts, but until then, it simply appears that exposure to space radiation increases your risk of cataracts later in life.  Advances in and the regularity of surgically-implanted interocular lenses make cataracts less of a concern, but effects like these are something for the aspiring casual spaceflight participant as well as for future planetary and deep space explorers to be aware of.





Dealing with space contamination

24 08 2010

Operation of LOCAD-PTS swabbing unit on the palm of a NASA spacesuit during simulated activities at Meteor Crater, Arizona; 09/2005. Credit: Dr. Jake Maule.

Planetary Protection, despite how it sounds, does not refer to a Bruce-Willis-style suicide mission to save Earth from an incoming asteroid.  However, it is one of those practical space exploration concerns that will only get more important with time.

So, what is planetary protection (PP)?

Think of it as the discipline of preventing the spread of interplanetary biological contamination, either from or to Earth, by astronauts, rovers, and anything else we might send between worlds.

For instance, what good is the search for life on another world if we actually deliver it there, (e.g., bacteria hitching a ride on the outside of a spacecraft) – or worse – if we accidentally contaminate the site and kill the life we’re looking for?

To this end, NASA scientists have been developing the LOCAD-PTS, which stands for Lab-on-a-Chip Application Development-Portable Test System.  Much like a Star Trek “tricorder,” the handheld device includes an electronic swab wand and onboard processor designed for the rapid testing of biological substances.  In just 15 minutes, an analysis can be performed and contamination results delivered to a waiting astronaut.

NASA Astronaut Sunita Williams using the LOCAD aboard the International Space Station. Credit: NASA

A number of field tests have been performed with the system so far, with many actually performed in space on the International Space Station to determine how biological material is transferred from Earth to space, and to monitor the spread of that material while there.  Samples were taken both inside and outside the station.  Beyond contamination on the exterior of spacecraft being transported to another world, in a closed environment the movement of biological material is also important to ensure astronaut health.

Even better here is the famed NASA technology “trickle-down” effect.  The LOCAD system as tested by NASA will also be highly useful on Earth.

Applications of the LOCAD procedures and technology include not only science on Earth, but also detecting lethal viral outbreaks and helping first responders during a potential biological attack.

With the forethought of technology programs like this, not only will all worlds involved be kept more pristine, but any data gathered will be that much more defensible.  Here’s hoping that before too much longer, the offspring of the LOCAD will get to see some action off-world.





Confronting radiation fears through symbology

14 06 2010

Traditional Radiation Trefoil Hazard Symbol.

Just a quick note today on radiation and the irrational fear it provokes.  -Take it from someone who works around “rad” professionally in nature and in industry: Radiation isn’t scary.  It’s normal.

Radiation comes from the sun above, the mountains around, the soil beneath, our wi-fi routers, radio stations, and heck – our own bodies emit infrared and gamma radiation, just like radioactive waste.  (Though, granted, at a much lower intensity.)

Micro-waves are, literally, radiation. Yes, you "nuke" your food in a microwave oven, (though there's no danger of making the food radioactive itself.) Microwave radiation is harmful, which is why all microwave ovens are discreetly engineered as "Faraday Cages" - the same protective housings that the military uses to protect sensitive electronics from nuclear blasts.

While some radioactive elements emit particles as well as “energy,” the simple truth is that the same electromagnetic waves that stimulate our retinas (visible light) are identical in form to the elctromagnetic waves that warm our hands in gloves (infrared rays,) cook our food (microwaves,) burn our skin (ultraviolet waves,) check our bones (x-rays,) and that on the extreme end can be very physically harmful to our tissue (gamma-rays and cosmic rays).  Think of them as colors our eyes can’t see.

That’s it.  That’s all there is to it.  Radiation is natural, not just man-made.  We grew up around it, and our bodies are built to take it.  There’s even a fair amount of serious research to suggest moderate exposure to radiation helps keep us healthy by stimulating our defense systems.

So, why the mystique?  Tradition.  Radiation is associated with atomic bombs, nuclear holocaust, physics perceived to be too complex for any ordianry person to understand (which is completely untrue,) and it’s invisible to human senses.  General misunderstanding is the culprit when we really have nothing to fear but… yes, fear itself.

Radio waves are radiation, too, (even though the waves are generally too large to cause harm to our bodies.)

Now – this fear is really getting in the way of some important developments in power, propulsion, and industry.  What can we do to counter such pervasive fear?  Perhaps we should call it like it is.

See the included examples of microwave, radio, etc., radiation symbols that accurately place radiation with radiation.  Enough with the marketing – call an apple an apple. 

Perhaps if we started putting these symbols out with our appliances and various gadgets and at beaches to denote the threat of sunburns and skin-cancer, we’d realize that not all radiation is truly harmful, and that the radiation that is a hazard is something we’re more than capable of dealing with – and that we really already do.  After all, what is sunscreen but a mild, high-density radiation shield?  (Ever wonder why sunscreen is so thick?)

Two cents.

Perhaps something like this out at pool decks and beaches would stress the need for sunscreen? It's compeltely scientifically and technically accurate, too...








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