Friday, June 29, 2012

Mutants and Superpowers: Radiation on the Big Screen

If there’s anything I’ve learned from Hollywood lately, it’s that a strong dose of radiation can do just about anything. Superhero movies are all over, and as blockbusters based on nostalgic comic book characters continue to fill theatres and set records, I can’t help but notice how much reference to radiation is made.  Radiation is responsible for Bruce Banner’s transformation to the Hulk, the fateful spider bite that begins Peter Parkers career as Spiderman, and shows the Avengers the way to the Tesseract – an all-powerful energy source that threatens earth.
Radiation continues to play an important role in modern media. source
Even with the knowledge that fiction is generally much more fun to watch than reality, why is radiation such a staple for script writers?  One possible explanation is the mysterious nature of radiation.  Scientists are still filling in the gaps about how radiation really affects humans and animals.  Long-tem low-level radiation exposure is an especially mysterious realm, due to the fact that so much time is required for testing and large man-made radiation sources have only been around since the early 1900s.

What we can take away is that Hollywood’s version of radioactive effects is very different from what really happens in the natural world.  Let’s take the example of genetic mutation.  We all know the story: ____ normal person is accidentally exposed to ____ source of radiation and instantly acquires ____ power.  The natural world argues that there simply isn’t enough time for this to happen. That’s because radiation affects the human body at the cellular level. 

Peter Parker and the radioactive spider. source
Radiation definitely makes changes to cell structure either by directly changing molecules or by creating charged particles that travel around the body and make changes (known as free radicals).  Serious problems can arise when radiation makes changes in strands of DNA, the microscopic blueprints of cells.  In these cases, radiation can cause cancer if the cell is not completely killed.  Cancer is produced if radiation creates an error in the DNA blueprint that contributes to eventual loss of control of cell division, and the cell begins dividing uncontrollably. This effect might not appear for many years – just as many other effects from radiation including cell mutations.

Cellular mutation is not only a regular occurrence in the natural world, it is also serves as the base of evolutionary change.  As random cell mutations occur due to environmental effects such as radiation or just biological functions, only the fittest survive.  Successful and efficient organisms (and their constituent cells) are able to survive and reproduce while weaker ones die out.  Although minor evolutionary changes can occur quickly in isolated organism groups, major adaptations can take millions of years.  Although we understand that this time frame could be problematic for plot development, overnight genetic mutations just can’t happen.
Blue eyes are a product of recent genetic mutation; only 6,000-10,000 years ago changes to the human genome allowed for light-colored eyes. source
Surprisingly, one recent scientific discovery paints a very Hollywood-esque picture of mutation.  A medical study on the inhabitants of the Kerala peninsula in India focused on the effects of very high background radiation on humans.  This area contains the highest background levels anywhere in the world – more than ten times the global average.  The data collected shows relatively normal levels of cancers, but increased levels of cellular mutation that gets passed down from mothers to children.  Furthermore, the surrounding wildlife was observed to contain accelerated mutation rates.  Scientists concluded that the heightened radiation level here has been linked to accelerated mutations for many organisms, creating an evolutionary hotspot for at least the last 60,000 years.  That means that more new organisms are found here as well as heightened levels of adaptation for existing organisms.

Even though overnight genetic mutations are unlikely, radiation is definitely effective to speed up mutation rates.  In the end, although spontaneous superpowers derived from radiation may not match physical phenomena, they sure are fun to watch.
D-tect Systems is a supplier of advanced radiation and chemical detection equipment sold around the world.

Thursday, June 7, 2012

Radiation on the Move

Radioactive materials have a nasty habit – they like to travel.  This phenomenon has caused panic at various times in history after nuclear events and accidents, and continues to do so these days. The nuclear disaster at Chernobyl created clouds of radioactive dust that swept across great swaths of Eastern Europe. Because most of the radiation was leaked into the environment when explosions and resulting fires destroyed the plant, the particles carrying radioactive material were very small and were carried easily by weather patterns. With little warning and even less monitoring, thousands were exposed to unknown amounts of radiation.

As the cleanup of the Fukushima Daiichi Nuclear Complex proceeds, we see a continuation of the same trend. Minute radioactive particles in steam and smoke rose into the atmosphere and were dispersed by wind and rain.  In addition, the proximity of the Fukushima plant to the ocean exacerbated contamination as an immense amount of contaminated ground water leaked into the sea. Although some of the more short-lived radioactive isotopes (such as I-131) soon faded, longer-lasting isotopes continue to cause problems as they travel and coalesce in unexpected areas. The contamination has posed such a problem in ecosystems near the plant that TEPCO began pouring concrete over 786,000 sq. ft. of seafloor near the accident site to encase radioactive materials1.

A recent study published in the journal Proceedings of the National Academy of Science shows another example of traveling radiation. Pacific bluefin tuna were discovered to have carried radiation from the Japanese coast to the shores of Monterrey, California in their annual migrations2. This news is surprising because scientists expected radioactive material to be metabolized and shed by the fish much earlier in their vast migratory movements. The isotopes found were not at dangerous levels for consumption, but definitely identifiable as cesium-134 does not occur naturally in the Pacific Ocean and cesium-137 only occurs at minimal levels. 
Tuna caught off the coast of California are found to have traces of radiation originating in Japan. source
This discovery illustrates how easily radiation can spread even great distances, and is a signal that constant widespread monitoring needs to be part of the Fukushima contamination solution. As radiation continues to travel and settle, we need detectors capable of notifying the public of these trends. Only with increased detection capabilities and constant monitoring can we truly understand the travel patterns of radiation. 
D-tect Systems is a supplier of advanced radiation and chemical detection equipment sold around the world.