Book Review: The Zombie Survival Guide: Recorded Attacks

Late last year I reviewed Max Brooks' 2006 novel World War Z, the follow-up to The Zombie Survival Guide, published in 2003. While the bulk of the Guide consists of tips for surviving a zombie apocalypse, my favorite part is the "Recorded Attacks" chapter, which illustrates that the zombie virus, solanum, has been infecting humans for thousands of years. Thanks to limited human interaction between continents and secret zombie-fighting groups like the Japanese Shield Society, the world had avoided a global pandemic (until World War Z, that is).

The Zombie Survival Guide contains just over 60 recorded events, ranging from an African outbreak in 60,000 B.C. (as recorded in cave paintings), to a case in the U.S. Virgin Islands in 2002. Theses events are presented clinically, like Brooks' other publications, which actually makes them more effective.

In keeping with the current trend of releasing graphic novels as tie-ins to popular books, in 2009 Brooks published The Zombie Survival Guide: Recorded Attacks, which contains illustrated adaptations of 12 of the Guide's historical events. I'm not certain how they chose which stories to include, but it seems that most of the stories in Recorded Attacks are those that the Guide presents with the most detail or that are the most "historically" relevant. However, I suspect that at least a couple were included because they were particularly gruesome in illustrated form.

The comic books I grew up on were a lot different

Recorded Attacks primarily lets the pictures do the talking. The illustrator, Ibraim Roberson, using a limited palette of black, white, and gray, ably depicts the horror and the tremendous amount of gore that we only imaged in the previous books.

What text we do get is used to set the seen or to clarify what we're seeing. It consists mostly of blurbs lifted from the Guide's Recorded Attacks chapter and thus carries the same cold, factual tone as the previous book. The contrast between the matter-of-fact text and the visceral images is extraordinarily effective.

A Word on Content
Obviously The Zombie Survival Guide: Recorded Attacks is filled with images of violence; it's a graphic novel about zombie attacks, after all. The illustrations may be in black and white, but the lack of color does little to reduce their impact. Additionally, Recorded Attacks contains a few scenes of non-sexual nudity. One involves the "corpse" of a young woman that is removed from a shallow grave (she quickly attacks those who disinterred her) while another shows a partially dressed woman chained up in the hold of a slave ship along with dozens of other slaves.

I would strongly recommend this book to zombie fans, particularly those who enjoy the horrifying ghoul-plagued universe that Max Brooks has created. And it should go without saying that I can only recommend it to mature adults who are not easily offended.
A-

On the INL Plutonium Exposure Controversy

Warning! Do not eat the plutonium!

Recently, my mother brought an AP article published in the Idaho Falls Post-Register and the online version of The Oregonian to my attention. The article briefly discusses a complaint filed with OSHA against Battelle Energy Alliance (BEA) by two employees. In 2011, 16 employees, including the two who filed the complaint, were exposed to plutonium contamination at the Materials and Fuels Complex (MFC), which is one of the many facilities at the Idaho National Laboratory (INL) (the official Accident Investigation Report can be found here). Of course, the article actually says that they were exposed to "plutonium radiation", which once again shows that the media has no interest in learning the difference between radiation and radioactive contamination. Anyway, as part of their complaint, the two employees claim that the 2011 incident occurred after they had expressed safety concerns over several different jobs.

Let me start by saying that I don't deny that the employees involved have a genuine complaint with regards to the incident itself. Had they been assigned to work a properly planned and engineered job, the spread of contamination would have been avoided. As a matter of fact, I heard about the incident the day it happened; my first response was "why didn't they just use a glovebox?" I wasn't too surprised when I found that Table C-1 in the official report states that the problem would not have occured if they had done exactly that.

Regardless of the errors made, I have a low tolerance for the perpetuation of inaccuracies or falsehoods with regards to the nuclear field. While I could criticize or question the article's statements (and the employees' complaints if it's assumed that the article accurately reports them) on several of fronts, I want to address a detail that is completely wrong. Specifically, one of the primary examples given of a safety concern that was supposedly ignored by BEA turns out not to have been a safety problem at all in light of the radioactive properties of plutonium. The fact that the workers still believe that it was an issue shows that the January 2012 report's statement that "Workers did not understand the consequences of Pu contamination" apparently remains true. According to the article:

Twice in 2011, BEA allegedly refused to allow Stanton and Simmons to use lead shielding to protect themselves when handling plutonium. Both workers exercised their right to stop the jobs, according to the complaint.

Let me cover a few of the most basic radiation types encountered in nuclear power and then we'll see why this particular claim is entirely baseless.

Alpha Radiation: Alpha radiation or alpha decay is the emission of particles from a radioactive isotope. These particles have two protons and two neutrons and are simply helium nuclei with a significant amount of kinetic energy. However, alpha particles present very little external risk since their kinetic energy is expended after traveling through a few centimeters of air or striking something as flimsy as paper or the dead layer of cells on a person's skin. Once stopped, an alpha particle is rendered harmless. Alpha particles only become dangerous when a strong alpha-emitting isotope enters the body. Internal tissues can become severely damaged since they aren't protected by a dead layer of cells like the skin is.

Beta Radiation: Beta radiation is the emission of electrons or positrons (which have the same mass as an electron but are positively charged) from the nucleus of a radioactive isotope. Beta particles don't have as much kinetic energy as alpha particles, although they have greater penetrating power. A beta particle can be stopped by sheets of metal, plastic, or glass. While beta particles have the potential to penetrate the outer layers of a person's skin, personnel working with a beta-emitting isotope are generally protected by the plastic walls of a glove box or by anti-contamination clothing. Since beta particles can penetrate the cornea, personnel may wear goggles or a face shield to protect their eyes.

Gamma Radiation: Gamma radiation is the emission of high energy photons with high penetrating power. Dense materials such as lead or steel are typically used to shield significant gamma-emitting sources, although a generous layer of water or concrete can perform the same function.

Neutron Radiation: Neutron radiation is the emission of free neutrons that usually occurs as the result of nuclear fission. Neutrons can also be produced by exposing certain light elements such as beryllium to an alpha-emitter. Neutron radiation is only effectively shielded by water or other hydrogenous materials such as oil or polymers.

Here's where the INL workers' complaint about the lead shielding falls apart. The workers claim that they weren't allowed to use lead shielding to protect themselves while working with plutonium. However, as I mentioned above, dense shielding is used to protect against gamma radiation, which is highly penetrating. Plutonium, on the other hand, is an alpha-emitter. Unless you have a critical mass (in which case you've started a lethal fission reaction and anything short of a reactor vessel isn't going to save you), plutonium is only a threat if it gets inside your body. As explicitly stated by the EPA, the external risk presented by plutonium is very small since it emits almost no gamma or beta radiation. BEA did not endanger the two employees by disallowing them from using lead shielding since such shielding is completely unnecessary to protect people from an alpha-emitter like plutonium.

I can understand why BEA would have disallowed its employees from using lead shielding while working with plutonium. Once BEA had conceded to allowing two employees to install useless shielding because it made them feel better, the company would be compelled to use "feel-good" shielding all the time. The allowance would simply perpetuate the myth among employees that lead shielding is effective and necessary for handling plutonium. Personally, I would never engineer a job to use unnecessary shielding for that very reason, although I would make sure to explain my reasoning to the workers to avoid any misunderstandings.

There's a lot more I could say about the article and the complaint filed by the two employees (I actually deleted a third of my draft before posting because it became too long and unfocused). For example, I believe that the purported retaliation didn't necessarily have sinister motivations, although I don't have any inside sources on this matter. The employees' claim that their radiation dosage information was withheld might sound suspicious, but may simply reflect the fact that dose assessments following exposure to an alpha-emitter are very difficult to perform. Page 61 of the accident report acknowledges that the measurements needed to complete the assessment might have to made over a period of months or even years.

Nuclear power has many enemies who latch onto any accusation of safety violations in support of their cause. Much too often, these anti-nuclear groups take advantage of the public's ignorance of the science to get their way. Inaccuracies like those found in the AP article and the employees' complaint are inevitably used to frighten the public away from an effective and safe form of power.

[The above represents my own opinions and does not necessarily reflect the opinions of my employer, BEA, or the INL.]

That's Not a Dinosaur!

Yesterday I was reading one of the How Do Dinosaurs... books to Son of Atomic Spud. (Much to my disappointment, the boy focused on the basketballs and footballs found on nearly each page more than he paid attention to the dinosaurs.) These books are part of a series intended to encourage good behavior in children. Each page features a dinosaur in an everyday situation surrounded by human children and adults; the dinosaur essentially represents a child who likes to pretend that he or she is a dinosaur. Usually the first half of each book shows the dinosaur misbehaving while the second half juxtaposes the proper behavior. This description may make the books sound preachy, but they're actually very well done.

My only real gripe about the books is that they often include prehistoric animals that, although many people seem to think that they're dinosaurs, are not actually dinosaurs. For example, Dimetrodon and various species of pterosaurs often make an appearance, but they simply are not dinosaurs.

Although there are a number of features that distinguish dinosaurs from other prehistoric animals, there are several ways to quickly tell when an animal is not a dinosaur. It's not a dinosaur if:

• It was a flying animal
• It was exclusively aquatic
• It had sprawled legs like a lizard or a crocodile
• It lived before or after the Mesozoic Era, which consisted of the Triassic, Jurassic, and Cretaceous Periods

There are a few animals that seem to be most often misidentified as dinosaurs:

Dimetrodon

Dimetrodon

Dimetrodon fails the dinosaur test in a number of ways. First of all, this popular sail-backed creature lived during the Permian Period, which was the final geologic period of the Paleozoic Era. Dinosaurs didn't appear until the first period of the following era (i.e., the Triassic Period of the Mesozoic Era). It's believed that the last Dimetrodon went extinct 40 million years before the first dinosaurs walked the earth.

A less obvious way in which Dimetrodon is not a dinosaur is the fact that its physiology shows it to be a synapsid rather than a sauropsid. Dinosaurs, existing reptiles, and birds are sauropsids while Dimetrodon and mammals are synapsids. In other words, according to current theories of phylogony, Dimetrodon is more closely related to mammals that it is to dinosaurs.

Dimetrodon: The sprawled legs show that it's not a dinosaur

The fastest way to tell that Dimetrodon wasn't a dinosaur is the fact that its legs sprawled out from its body. Thanks to the shape of their hip sockets and femurs, dinosaur legs were erect rather than sprawled to the sides. Remember, if it walked like a crocodile, it's not a dinosaur.

Pterosaurs

Pteranodon

The order Pterosauria includes the well-known genera Pterodactylus and Pteranodon. These flying reptiles lived around the same time as the dinosaurs (i.e., the Triassic Period to the Cretaceous Period). Also, like dinosaurs, the Pterosaurs were part of the Archosaur group. (Modern Archosaurs include crocodilians and birds.) However, Pterosaurs are not classified as dinosaurs, which were exclusively land-dwelling animals. And it's fairly obvious that Pterosaurs didn't have the same upright limbs as dinosaurs.

It's believed that the pterosaurs' and dinosaurs' last common ancestor lived during the Early Triassic, which ended about 245 million years ago. The first dinosaurs seem to have appeared about 230 million years ago during the Middle to Late Triassic, while the first Pterosaurs appeared about 210 million years ago.

Pterosaurs: Flying shows that they're not dinosaurs

Plesiosaurs and Mosasaurs
Like the Pterosaurs, the Plesiosaurs and the Mosasaurs also lived during the time of the dinosaurs. However, since they were specifically adapted to aquatic life, they are not dinosaurs.

Elasmosaurus

While the Mosasaurs don't really resemble dinosaurs and don't seem to be confused with them as often, the fact that the Plesiosaurs aren't dinosaurs might be confusing to some people. In the popular mind, a Plesiosaur like Elasmosaurus looks a lot like a sauropod (e.g., Brachiosaurus, Apatosaurus) but with flippers instead of legs.

Mosasaurus

Despite their physical similarities, it turns out that the relationship between Plesiosaurs and dinosaurs is even more distant than that between the Pterosaurs and dinosaurs. At least the latter two are both Archosaurs. The Plesiosaurs are part of the Sauropterygian group that first appeared around 245 million years ago and developed alongside the Archosauromorpha group (i.e., the group that eventually gave rise to the Archosaurs).

A Plesiosaur: The flippers show it's not a dinosaur

Similarly, the Mosasaurs are only distantly related to dinosaurs. They were part of the Lepidosauromorpha group, of which modern lizards and snakes are a part.

A Mosasaur

Remember, if it walked like a crocodile, flew, or lived only in the water, it's not a dinosaur.

Now I Really Am the Atomic Spud

A few months ago I started getting odd pains after eating. The symptoms weren't like those of the acid reflux I've had for most of my life (and can control most of the time with Prilosec), but they did seem similar to the pains my wife had been having off and on for a few years. We found out last year that she had a pyloric ulcer as well as gallbladder disease; the former was treated with expensive medications and the latter was taken care of through gallbladder removal surgery. Since we didn't know which of her symptoms was caused by what ailment, we really couldn't say if my problem was caused by an ulcer (pyloric ulcers are the result of bacterial infection and can be spread from person to person) or by a gallbladder problem.

A visit to the doctor a few weeks ago indicated that I don't have an ulcer. A simple blood test showed that I didn't have the bacterial infection and the description of my symptoms didn't seem to match up with those of an ulcer. According to the doctor, certain symptoms I've been having are characteristic of a malfunctioning gallbladder. The doctor explained to me that the first technique we could use to confirm his suspicions would be to look for gallstones using ultrasound. If that came up negative, we could monitor the gallbladder's function with a HIDA scan. He warned me that it's possible for both techniques to yield negative results and to still have gallbladder disease. Last week I had a sonogram that showed that I didn't have any gallstones. On Friday morning I went in for the HIDA scan. I came out of the scan radioactive.

Yep, that's me

Prior to a HIDA scan, the patient is injected with the radioactive isotope Technetium-99m (Tc-99m). The Tc-99m eventually ends up in the person's bile and can be seen passing through the gallbladder with a radiation-detecting scanner. In my case, I was also injected with a medicine near the end of the scan that exercises the gallbladder as if I had eaten a fatty meal. The function of the organ was monitored and I was instructed to tell the technician whether or not the injection recreated the pain.

Hours of gamma radiation-emitting fun

I have yet to receive the results of my scan, but the final injection caused a relatively mild form of the discomfort I've been having. As for the radioactivity, I was injected with 6 millicuries (mCi) of Tc-99m. Six thousandths of a curie seems like a lot to someone who typically works in units of picocuries (pCi), or trillionths of a curie. Of course, the isotopes I work with emit a lot more energy per curie than Tc-99m. The relatively low energy of the gamma photon emitted when Tc-99m transitions to Tc-99 is much of the reason why this form of Technetium is used for medical diagnostics.

Anyway, if my experience is anything like those of the people who received the diagnostic, happened to have a Geiger counter at home, and posted the results on the Internet (oddly enough, I'm not one of those people), I probably left the clinic with an on-contact radiation reading between 20 and 30 millirem/hr. (Objectively, this is not a very high level, but at work we would consider implementing certain controls when dealing with an item emitting that level of radiation.) Tc-99m has a half-life of 6 hours, meaning that the radiation level is halved every six hours. The effective levels may drop even faster since the radioisotope will also leave the body through the urine. Given my line of work and the caution with which we treat radiation and contamination, it's amusing to think that I am currently an unmarked, walking radiation source and that I'm simply dumping radioactivity into the sewers every time I flush the toilet.

Most sources suggest that I'll have received about 500 millirem of exposure by the time the Tc-99m is out of my system. Although this is not an insignificant level of exposure over such a short period of time, it is still far from being dangerous. It is also a lot higher than the amount I've received at my facility since I started there several years ago. Occupational radiation exposure is monitored separately from that of other sources (e.g., medical treatments). Thus, I won't be allowed to wear a dosimeter when I go back to work next week until I'm scanned by a radiological controls technician and am declared to have returned to background radiation levels. I look forward to finding out my radiation level on Monday so I can back-calculate the level I reached when I was first injected.

I wonder what super powers I'll get

UPDATE: 2/13/12
First thing this morning a radiological controls technician checked my radiation levels. Between Tc-99m's short half life and the soda and Powerade I was drinking to flush out my system, I had returned to background levels. And since I don't know when I got rid of most of the isotope, I can't even back-calculate my original levels. The worst part is that I don't have a single super power to show for it.

This Day In History: The Apollo 11 Moon Landing

On this day in 1969 Apollo 11 astronauts Neil Armstrong and Edwin "Buzz" Aldrin landed on the surface of the moon in the Lunar Module Eagle. Mission pilot Michael Collins remained in lunar orbit in the Command Module Columbia.

Armstrong and Aldrin spent 21 hours and 31 minutes on the lunar surface before returning to Columbia. Although Collins' contribution is overshadowed by that of his compatriots, he played a vital role in the success of the mission. Later astronauts would spend over three days on the surface.

I don't think mankind has done anything quite as cool since then.

Electric Cars Not So Green After All

Electric cars: more total
emissions than standard cars?

I love it when self-righteous environmentalists are made to look like fools. I got my day's worth of schadenfraude from this article on the environmental impact of "green" electric cars:

An electric car owner would have to drive at least 129,000 km [80,157 miles] before producing a net saving in CO2. Many electric cars will not travel that far in their lifetime because they typically have a range of less than 145 km [90 miles] on a single charge and are unsuitable for long trips. Even those driven 160,000 km [99,419 miles] would save only about a tonne [1.1 tons] of CO2 over their lifetimes.

As pretty much any engineer who has even a rudimentary understanding of the kind of batteries used in electric cars could tell you, a lot of energy goes into making those batteries. Thus:

... a mid-size electric car would produce 23.1 tonnes [25.5 tons] of CO2 over its lifetime, compared with 24 tonnes [26.4 tons] for a similar petrol car. Emissions from manufacturing electric cars are at least 50 per cent higher because batteries are made from materials such as lithium, copper and refined silicon, which require much energy to be processed.

Just as it does with nearly every other pie-in-the-sky environmental fad, the US Government is heavily subsiding electric cars such as the Chevy Volt. Politicians claim that they're doing this for environmental reasons, although I'm sure auto industry lobbyists and the United Auto Worker's Union also have a lot to do with it. Either way, this study shows us that our supposed representatives are again spending our money/our children's money on something they don't understand and that doesn't live up to its promises once you actually look into the messy details and unintended consequences.

I'm reminded of then-Governor Arnold Schwarzenegger's 2004 State of the State address that encouraged Californians to switch to hydrogen-fueled cars. Why not, asks the politician, since hydrogen is the most abundant element in the universe and it burns cleanly (the end result is water vapor)? Of course, a basic understanding of chemistry would tell you that the reactivity of hydrogen ensures that it's not found in an elemental state on Earth and that it therefore must be separated from whatever other element(s) it's attached to. This process usually requires a significant amount of energy. In addition, hydrogen is difficult to transport or store.

Whether the car is electrical or hydrogen powered, energy must be consumed to either charge the car or to create its fuel. Since about 68% of US electricity is produced by burning fossil fuels (with coal accounting for much of it), these alternative fuel vehicles are likely to actually increase total emissions since more "dirty" electricity would need to be produced to run "clean" cars. And, thanks to the second law of thermodynamics, the more energy conversions you introduce, the more inefficient your total process becomes. There are a number of conversion processes needed to run an electric car, each of them introducing significant inefficiencies; e.g., burning coal to heat steam, using steam to spin a generator, spinning a generator to produce electricity, using electricity to charge a battery, and using a battery to run a car's electric motor. In short, a huge amount of energy has to be produced at the beginning of the process just to provide the relatively small amount of useful energy needed to operate the car.

I think one of the best arguments for limited government is the fact that politicians regularly waste huge sums of money and force burdensome regulations or mandates on us based on insufficient or incorrect information. Should we really give so much power to a small group of elite ignoramuses?

Kids and Fantasy Violence

Yesterday afternoon I watched an episode of Mythbusters with my daughters. The episode tested the truth of the saying 'to slap some sense' into a person. They established their baseline by putting Grant through an obstacle course testing both cognitive abilities and reflexes and, later on, by putting Tory and Kari through a shooting range used for police training. After getting their baseline, they then impaired their performance by spending thirty minutes in a freezing room (Grant) or by combining sleep deprivation, fasting, and a thirty minute chill (Tory and Kari) and then repeating the test. Finally, they repeated the impaired test except that they slapped the person once across the face with a bungee-powered slapping machine beforehand. In all three cases the slap significantly compensated for the impairment, although they still fell short of their baseline. Apparently the slap initiated the fight-or-flight instinct that caused the improvement.

We got to see this over and over again in slow-motion

Later that evening, my older daughter and I watched Star Wars: The Clone Wars. In that particular episode, Anakin Skywalker's apprentice, Ahsoka, found herself and three other Jedi trainees being hunted by trandoshans (an intelligent reptilian species). The episode contained the typical amount of violence seen in the series: several characters were shot, the Jedi slammed trandoshans into boulders and bulkheads with the Force, characters kicked and punched each other, and two characters fell to their deaths (with one of them actually becoming impaled on a stalagmite).

Wookies and trandoshans have never gotten along

Later on I asked my daughter if she liked watching Mythbusters and if she thought it was funny when the mythbusters were being slapped by the machine. She thought about it for a moment and then said that the episode was okay but that she didn't like that Tory, Kari, and Grant were being hurt and that she had felt bad for them. When I asked if she liked the episode of The Clone Wars she got very excited and talked endlessly about how much she enjoyed it when the Jedi and the wookies were beating up the trandoshans. In fact, I believe that nearly all the trandoshans were dead by the end of the episode.

My daughter's reaction to the two different shows reminds me of a very interesting book I read several years ago called Killing Monsters. The book's subtitle declares that "children need fantasy, super heroes, and make-believe violence". The author, Gerard Jones, argues that children can generally distinguish between real violence and fantasy violence and that fantasy violence helps them to cope with the frightening things around them while also serving as an outlet for aggressive emotions. Jones goes even farther and suggests that children who are not allowed to relieve these emotions through make-believe violence may later seek out more realistic forms of it; e.g., extremely violent films and music, animal cruelty, or even by the infliction of it on their peers or family.

Several times I've seen parents or teachers get whipped into a panic because some preschool-aged boy pointed his finger at another child and said "bang, I shot you". Several cases of a "zero-tolerance policy" run amok have made nationwide news, with kids getting suspended from school for normal childhood behavior such as having a "simulated weapon" (this can include "finger guns" and inch long G.I. Joe action figure guns). It's as if these adults have completely forgotten that generations of children have pretended to shoot, stab, or bludgeon each other (some of the earliest identifiable toys were wooden swords used by Roman children) without becoming murderous psychopaths. One of Jones' strongest arguments is that the common presence of realistic toy guns among the baby-boomer generation didn't result in an epidemic of actual violence. And I think I can guarantee that the very adults responsible for many of these ridiculous zero-tolerance policies laughed years before when, as children watching Saturday morning cartoons, they saw Elmer Fudd blast Daffy Duck's beak off with a shotgun.

Although the mythbusters took the slaps in good humor, they obviously didn't enjoy them and my daughter didn't like watching real people get hurt. At the same time, she enjoyed the fantasy violence of Star Wars and later pretended that Son of Atomic Spud and I were Sith Lords and that she was slashing us up with a lightsaber. I wish that more adults were as mature about make-believe violence and as capable of distinguishing it from real violence as most children are.

More Baseless Nuclear Panic

Thanks to the Fukushima accident, my coworkers and I have found ourselves fielding questions from friends and family because the media has been too busy sensationalizing and ax-grinding to do some basic research. I've tried to summarize the relevant information on this page. Unfortunately, there seems to be more panic among Americans than among the much more stalwart Japanese.

The latest unfounded fears I've come across are coming out of Boise, Idaho. Due to the Fukushima accident, elevated levels of the radioactive isotope iodine-131 were found in Boise's rainfall and drinking water. Of course, this has some people panicking. "Anonymous Coward" posted this on one forum:

We are going to get a very concentrated dose of radioactive materials tomorrow in Boise, Idaho PLUS a 90% chance of rain. Cesium 137 was detected here by air filter and rainwater. The next three days if not longer are going to be bad but it looks like only tomorrow will be raining.

Should I keep my child home from school tomorrow? Am I overreacting? Wwyd? P.S. Yesterday I felt fine, today I have feelings in my throat and a weird headache and it's raining.

Others in the forum advised the poster to keep her child out of the rain due to "high levels of iodine 131", to treat her drinking water with various "detoxification" substances, or to allow her child out in the rain to build up a tolerance because "she has many years of exposure to come." How can we have nearly all of mankind's knowledge at our fingertips thanks to the Internet and yet keep finding absurd advice like this?

It doesn't take a whole lot of research to show that Anonymous Coward's throat problems and "weird headache" are psychosomatic and not the result of radiation sickness. First of all, let's review the actual report that has some people scared. Here's the EPA's statement on precipitation from April 4, 2011:

[P]recipitation data collected in several states show elevated levels of radiation in recent precipitation events. In all cases these are levels above the normal background levels historically reported in these areas. While short-term elevations such as these do not raise public health concerns – and the levels seen in rainwater are expected to be relatively short in duration – the U.S. EPA has taken steps to increase the level of monitoring of precipitation, drinking water, and other potential exposure routes to continue to verify that. (emphasis mine)

Despite the EPA's statement that there is no public health concern, many people seem to have focused on the report's table stating that 242 pCi/L was measured in the local precipitation on March 22 (the level of cesium-137 was about 20 times lower). My coworkers and I have had a good laugh that this number has caused an uproar among some people. The pCi (pronounced "picocurie", meaning 1/1,000,000,000,000 of a curie) is an extremely small quantity of radioactivity, especially when diluted in a liter (L) of water. When we talk about contaminated water at work, we use units of µCi/mL (1/1,000,000 of a curie in 1 milliliter of water) because a pCi/L is such a small amount (1 µCi/mL is a billion times more than 1 pCi/L).

Not understanding what a small amount of radioactivity 242 pCi/L is, someone took that number, divided it by the EPA drinking water limit of 3 pCi/L for iodine-131, and then declared that "Boise rainwater has highest levels of radioactive material… 80 times amount of I-131 allowed in drinking water." Once again, someone has either failed to do their research or is deliberately trying to scare people.

Drinking Water versus Precipitation
Notice that the above calculation confuses precipitation with drinking water. The rain that has fallen since the Fukushima incident makes up only a small percentage of Boise's drinking water. So how much radioactive iodine has actually been found in the drinking water? From the EPA's April 4, 2011 statement on drinking water:

Drinking water samples from two locations, Boise, Idaho and Richland, Washington, showed trace amounts of Iodine-131 – about 0.2 picocuries per liter in each case. Even an infant would have to drink almost 7,000 liters of this water to receive a radiation dose equivalent to a day’s worth of the natural background radiation exposure we experience continuously from natural sources of radioactivity in our environment. (emphasis mine)

Even after the "very concentrated dose" of radioactivity in the rainwater on March 22, the drinking water in Boise contained a paltry 0.20 pCi/L on March 28. This isn't 80 times greater than the allowed EPA limit, it's 15 times less than the limit. And since iodine-131 has a half-life of about 8 days, the quantity of radioactive iodine will significantly decline over the coming weeks and months.

Conservatism of the EPA Limit
It's unfortunate that the unit of measurement used throughout the Fukushima crisis has been 'X times (normal levels, regulatory limits, etc.)'. I understand that this is an attempt to give people a sense of scale, but since most don't actually know the levels at which radiation or radioactivity become dangerous (and the media doesn't seem to be in a hurry to tell them) you end up with people who are in possession of the facts but don't know what they mean. For example, ten times the normal radiation levels sounds scary until you realize that normal radiation levels are nearly 100,000 times lower than the levels at which the signs of acute radiation sickness appear (the average American receives about 1 millirem (0.001 rem) per day from normal background radiation, while radiation sickness generally occurs after receiving about 100 rem).

The EPA's limit for iodine-131 in the drinking water is an average annual level of 3 pCi/L "so the public radiation dose will not exceed 4 millirem". The limit was chosen as one that was so low that a person could ingest it every day from infancy to old age with no statistically detectable ill effects. Like so many other EPA limits, this number is relatively arbitrary. Although levels vary, the Department of Energy has estimated that the average American receives 360 millirem/year due to background radiation (some have estimated even higher levels due to the increased use of certain medical technologies). The 4 millirem that one could get from drinking water containing the EPA limit of iodine-131 would therefore account for a mere 1% of the radiation a person would normally receive. Even if the scary '80 times the EPA limits for drinking water' were accurate, and if it were assumed (unrealistically) that levels in the water would remain elevated for a whole year, people in Boise would only receive an extra 320 millirem per year (4 millirem times 80) from the contaminated water. Compare that to the 5,000 millirem per year that nuclear workers are allowed to receive per Federal law. Also per Federal law, a pregnant nuclear worker is allowed to receive 500 millirem for the duration of the pregnancy. These Federal limits are what workers may receive beyond normal background exposure. In short, even in an unrealistic worse case scenario, the people of Boise would receive lower radiation doses than have been shown to be safe for unborn children (320 millirem versus 500 millirem).

Precedence
A brief review of the data shows that the 242 pCi/L of iodine-131 found in Boise's rainwater are less than the levels found after the Chernobyl accident in 1986. On May 8, 1986, 460 pCi/L were found in the rainwater in Portland, Oregon. On May 10, 530 pCi/L were found in Las Vegas, Nevada and 270 pCi/L were found in Olympia, Washington. In Ottawa, Canada even higher levels were found; samples taken on May 7, 1986 found 1,647 pCi/L in the rainwater. These levels were all higher than those found in the United States following the Fukushima accident, yet there were no cases of radiation sickness nor was there a noticeable increase in cancer rates in North America. According to the EPA, such levels are low enough that they "pose no threat to human health or the environment."

Even the contamination spread by the Chernobyl disaster is dwarfed by the amount of radioactive fallout produced by years of nuclear testing between the late 1940s and the early 1960s. The United States alone performed 331 nuclear weapons tests above ground (and even more underground). Many of these tests were conducted in Nevada, about 100 miles from Las Vegas, while the largest tests were performed in the Pacific. The Soviet Union conducted 715 tests, often without regard for the health of those living nearby. One Soviet test involved the largest nuclear weapon ever detonated (50 megatons versus the 15 megatons of America's Castle Bravo test). Each of these above ground tests blasted huge quantities of radioactive materials into the stratosphere. Since humanity somehow managed to survive almost twenty years of fallout resulting from the nuclear arms race, I think it's safe to say that Anonymous Coward of Boise, Idaho and her child will tolerate the radioactivity spread by the Fukushima accident just fine (I'm not sure how well she'll handle the psychosomatic effects, though).

Castle Romeo vs. Fukushima: which do you think caused more fallout?

In conclusion, as I've said before (here and here), the levels of contamination reaching the United States are very low and present a negligible risk to human health. Unfortunately, members of the American public who have little to no knowledge of nuclear power (e.g., Anonymous Coward) have latched onto numbers that seem large and have started to panic. This hasn't been helped by those who have taken a single day's measurement of radioactivity in rainfall (which yielded a number with units that they don't understand) and have compared it to a regulatory limit for drinking water (without understanding the origin of the limit or how that limit compares to actual biological effects). Rather than try to confirm or correct their perceptions using the power of the Internet, these people gather on various forums to scare each other instead. I find myself wondering how many of these people drive without wearing a seatbelt.

Nuclear Power and Relative Risk

A commenter on one of my recent posts said that "Every human enterprise involves some risk". This is the same message as a March 14th Wall Street Journal opinion article. In light of the ongoing Fukushima crisis, I think it's instructive to review the concept of relative risk.

Just looking at the statistics, I think the most obvious lesson of the Tōhoku earthquake and the resultant tsunami (i.e., the disasters that caused the Fukushima accident) is that it's more dangerous to live by the beach than it is to live by a nuclear plant. The earthquake and the tsunami (which caused most of the casualties) left a death-toll of around 10,000 people, while the nuclear accident has not officially killed anybody (although two workers are missing who may have been killed in an explosion). Yet the lesson that so many anti-nuclear activists and ordinary Americans will take away from the disaster is not that beachfront property may be a poor investment, but that nuclear power is dangerous and bad. In fact, even in light of the 230,000+ deaths caused by the 2004 Indian Ocean tsunami, I think most people would still like to own a home by the ocean.

Three Mile Island

I am always amazed by how risk-averse Americans are with regards to some things while having absolutely no trepidation about other things that are much more likely to kill or injure them. For example, nuclear power is one of those touchy subjects that causes panic or fear in millions of Americans. Yet the total number of Americans that have been demonstrably killed by nuclear power (not counting a handful of early incidents involving experimental bomb cores) is three. That's right; three people, all of whom were military personnel killed in the explosion of the experimental SL-1 reactor in 1961. One study suggests that one or two cancer deaths may have occurred after the Three Mile Island accident, but this number was determined statistically and cannot be confirmed. Worldwide there have only been 63 confirmed fatalities directly associated with nuclear power (this number omits weapons and military related incidents as well as the Fukushima crisis, which isn't quite finished yet).

Chernobyl

The Chernobyl disaster, which was caused by a poorly designed reactor and an ill-advised experiment that disabled essential safety systems, accounts for the bulk of the fatalities (53 out of the 63). However, it must be admitted that the official figure may be misleading since the Soviet Union was never known for releasing honest casualty figures. Shortly after the accident, the United Nations Scientific Committee of the Effects of Atomic Radiation (UNSCEAR) estimated that 4,000 people would suffer from cancer due to the accident (later reports suggested that this was an overestimate). Not all of these 4,000 people would have died prematurely since some types of cancer associated with radiation exposure (e.g., thyroid cancer) are relatively treatable and have a decent survival rate.

To prove my point about relative risk, let's begin by approximating how many people may have been killed by nuclear power. Since I couldn't possibly guess how effective Soviet medicine was in the 1980s, we'll just count all 4,000 potential cancer cases caused by Chernobyl as fatalities. Thus, an upper limit of 4,063 people may have been killed by nuclear plant accidents since 1961, with the vast majority of that number being questionable. If we divide that number by 57 years (the number of years that have passed between now and 1954, when the first nuclear reactor to provide power for an electrical grid came online) we end up with an average number of approximately 71 deaths per year due to nuclear power plants. Remember, this number was boosted by an estimated number of cancer cases that might have been incurred by the Chernobyl disaster. If we only use confirmed numbers then the average number of deaths per year drops to about 1.

A lot more deadly than any nuclear reactor

Using the exaggerated number of 71 deaths per year, it becomes horribly ironic that most anti-nuclear activists protesting at a nuclear power plant must have driven there. Every year around 30,000 to 40,000 Americans are killed in auto accidents. It is estimated that a worldwide total of 1.2 million people are killed annually in auto accidents. This means that, on average, nearly 17,000 times more people die annually in car accidents than in nuclear plant accidents. Clearly we're in the middle of an automobile-spawned apocalypse. So where are the anti-automobile activists?

Electricity: Threat or menace?

How about an energy source that we interact with daily? In 1993 550 people were killed by electricity in the United States. Given that US electrical safety standards are significantly higher than they are in parts of the developing world, the number of electrical fatalities worldwide is undoubtedly much higher. Either way, this number is almost eight times higher than our average annual rate of nuclear power-related deaths (this assumes that 550 is a fairly representative fatality rate for more recent years). Honestly, how can we even allow electricity into our homes when it's clearly so dangerous?

Windmills of DEATH

While we're throwing numbers around, it turns out that accidents involving wind power have killed 73 people between 1975 and 2010. Note that this number of fatalities (which were incurred over a period of 35 years) exceeds the 63 officially confirmed deaths caused by nuclear plant accidents (after 57 years of commercial nuclear power). The most common cause of windmill related accidents was blade failure. When a turbine blade fails, the blade or pieces of the blade can be thrown at a lethal velocity. Now that wind turbines are being built in ever greater numbers and closer to inhabited areas, we can only expect the number of accidents to go up. Too bad all those activists are too busy protesting nuclear plants to care about the windmill farms being built near residential areas.

Don't breathe too deep

Now that we're back on the subject of electricity production, let's talk about coal-produced power. In 2006 coal plants generated about 49% of America's electricity and 68.7% of China's electricity (nuclear power accounts for about 20% of US electricity). Ironically, because coal contains a number of naturally radioactive isotopes, it is estimated that US coal burning in 1982 released 155 times more radioactivity into the air than the Three Mile Island accident. Ignoring the effect of radioactivity, we find reports suggesting that 750,000 Chinese die prematurely each year due to air pollution. The World Health Organization has claimed that 2.4 million die each year due to air pollution. Much of this pollution comes from burning coal for electricity. Now, I know that there are anti-coal plant activists, but many of them are the kind that conveniently forget that coal power is a major source of the energy used to make solar cells, manufacture wind turbines, or to charge their "environmentally friendly" Chevy Volts. Modern life (which is more than 20 years longer and healthier than life in the early 20th century) would not be possible without the electricity produced by burning coal.

The point I'm trying to make is that human life is full of risks but that many people seem to be confused about what risks they should worry about. Even if the Fukushima accident turns out as bad as the most extreme estimates suggest (estimates which are almost invariably developed by anti-nuclear organizations), the number of deaths that could be caused by radiation sickness and radiation-induced cancer would be far exceeded by the number of auto deaths that occur in the United States in a single month. Yet most of the Americans who are stocking up on iodine tablets probably don't think twice about getting into a car (and I'd bet a good percentage of them don't even bother to put on a seatbelt). Although I spend every work day in close proximity with nuclear materials and energy, I know that the most dangerous part of my day is the drive to and from work.

An Update on the Fukushima Situation

Some of the following will make more sense if one has a basic understanding of the composition and construction of nuclear fuel. I provided a basic introduction to nuclear power in my last blog post and have created a standing page on the subject.

Fallout Over California
Previously I discussed the possibility of fallout from the Fukushima incident reaching the West Coast. Although I erred slightly when I said that the fallout "would probably be so widely dispersed that the radioactivity would be effectively undetectable" (I neglected the fact that radioactivity detection systems used to monitor nuclear weapons tests have become extremely effective), I was right when I also said that it "would have a negligible impact on public health". Recent reports indicate that the levels of contamination reaching the United States are "about a billion times beneath levels that would be health threatening".

Damage Control and Radiation Exposure

A damaged reactor building at
the Fukushima nuclear plant

In the meantime, nuclear plant workers (the heroic "Fukushima 50", although there are actually about 180 of them) have been attempting to stabilize the reactors. Working in shifts, these plant employees are being limited to 50 rem (0.5 Sv) total radiation exposure. This is ten times the annual Federal limit for radiation workers in the US but is about half the amount of exposure at which point the effects of acute radiation sickness can be felt; i.e., 100-200 rem (1-2 Sv). Although these workers will undoubtedly face an increased cancer risk in the future (perhaps four times greater than normal if they end up like Chernobyl's "Liquidators"), as long as they observe the 50 rem limit it is very unlikely that any of the Fukushima 50 will die from radiation sickness. In other words, the plant workers have been given a dangerous task, but it isn't a "suicide mission" as some in the media have called it.

Dry Cooling Pools
The latest reports also seem to indicate that some of the greatest problems being faced are not coming from the reactors themselves but from spent fuel cooling pools that may be going dry. If the fuel assemblies aren't being properly cooled they can become damaged due to decay heat. The zirconium cladding can bubble and burst open, releasing fission products into the air. Even worse, it is feared that the overheated zirconium alloys will begin to oxidize rapidly, which can result in a fire. In the presence of steam, the oxidation process can produce hydrogen gas. This process occurred earlier this week when hydrogen was created by the oxidation of the cladding of the overheated fuel assemblies inside the reactors. To reduce the likelihood of damage to the reactor vessels, operators vented the hydrogen out of the reactors and into the reactor buildings, which caused several explosions. The decision to vent the gas was definitely the right one since an explosion within the reactors would have been even more disastrous.

Given the potential consequences of allowing the cooling pools to dry out, plant workers have been desperately trying to refill them. However, in addition to cooling the fuel the water also provides radiation shielding. Without shielding, it is very difficult to approach the pools due to extremely high radiation levels.

An Introduction to Nuclear Power

As I've discussed recently, a lot of information on nuclear power has been long on hype and short on accurate information. My own experience with friends and family has shown me that many otherwise intelligent people have little to no understanding of nuclear power. I recommend that people refer to Wikipedia for detailed explanations of how nuclear fission works or how a nuclear reactor uses fission to make power, since those subjects deserve a more in-depth treatment than I can given them in a blog post. However, the news coming out of Japan may make more sense if we briefly review what nuclear fuel is and how the fuel works.

A uranium fuel pellet

Most commercial reactors use enriched uranium in the form of pellets for their fuel. Uranium consists mostly of the isotope uranium-238 along with a small amount of other isotopes. When uranium is enriched to be used as nuclear fuel, the isotope uranium-235 is increased above the 0.7% found in natural uranium (most power plants use fuel that's 3% to 5% uranium-235). As shown in the photo, these pellets are relatively safe to handle before undergoing nuclear fission. The pellets are sealed into tubes (often called "cladding"), which are usually composed of a zirconium alloy. Zirconium is the material of choice due to certain favorable properties, not the least of which is its near-transparency to neutrons (neutrons will have to be able to pass from one tube to the other in order to sustain a fission reaction). These tubes are then bundled together into fuel assemblies. In a boiling water reactor (BWR), like those used at Fukushima, the assemblies are encased in an additional thin-walled tube. A removable control rod is inserted into the fuel assembly to absorb neutrons and prevent a premature fission reaction. In a pressurized water reactor (PWR) (the most common reactor type in the United States), the control rods enter the fuel assembly from above; in a BWR the control rods enter from below. Notice that all elements of the fuel, the cladding, and the control rods are made of solid materials. I am always surprised to find that many people believe that nuclear fuel is some sort of glowing liquid.

Nuclear fuel rod assemblies

The assemblies are inserted in a reactor vessel and the vessel is sealed. To start up the reactor, the control rods are withdrawn. Neutrons produced by the spontaneous fission of a relatively small number of uranium atoms strike other uranium atoms nearby, which causes still more fissions. A nuclear chain reaction (or "criticality") occurs when, on average, at least one neutron produced by each fission goes on to produce an additional fission. The control rods are partially inserted or removed as necessary to keep the reaction at the desired rate. The control rods contain materials like cadmium or boron that absorb neutrons and prevent an excessive rate of fission. Water within the reactor cools the fuel assemblies, slows the emitted neutrons (slower neutrons are more effective at producing a fission reaction in uranium), and is used in conjunction with steam turbines to produce electricity. In a BWR, the fission reaction boils the water within the reactor vessel. In a PWR, the water in the vessel is maintained at a pressure that prevents it from boiling; the heat from the water in the pressurized "primary loop" is transferred to water in the "secondary loop", which is allowed to boil.

Fuel assemblies in a nuclear reactor opened for servicing

The typical commercial reactor will operate for about 12 to 24 months before the fuel must be replaced. By this time, much of the uranium-235 within the assemblies has been changed into fission products (some of the most common being iodine-131, cesium-137, and strontium-90). Isotopes of plutonium will have also been produced when neutrons were absorbed by atoms of uranium-238. The reactor is shut down by fully inserting the control rods. At this point the reactor is "subcritical", meaning that, on average, each fission produces less than one additional fission. The fuel assemblies are then removed from the reactor and are placed in a water-filled pit or pool. Although the nuclear chain reaction has been stopped, the water is required to cool the assemblies since radioactive decay of the fission products produces a significant amount of heat. Eventually the rate of decay will fall sufficiently that the fuel assemblies can be removed from the pool and be placed in a dry cask.

Spent fuel assemblies in a cooling pool

I'll be explaining what the above means for Fukushima in a later post.

Obama's Surgeon General Makes Things Worse

Let me start by saying that this whole Fukushima issue has me frustrated. An earthquake and tsunami kill tens of thousands of people and all the media can talk about are the problems that Japan is having with a handful of reactors. As serious as those problems are, to my knowledge no one has yet died or become seriously ill because of the partial meltdowns or the spread of radioactive contamination. The Wall Street Journal has a good article that discusses this unequal treatment. Also, I believe that America would greatly benefit from a greater exploitation of nuclear power. It is therefore immensely irritating to know that its opponents, with the aid of their useful idiots in the media, will use the Fukushima incident to further strangle the nuclear industry.

It's bad enough that the media seems to be deliberately conflating the nuclear accident with the tsunami's death toll (e.g., "Japan Digs for Thousands of Dead Amid Nuclear Crisis"), which appears to be an attempt to make unwary readers think that the accident at the power plant caused those deaths. And it sure hasn't helped that they've been distorting the science behind radiation and radioactivity. Now the ineptitude and ignorance of Obama's Surgeon General is actually making things worse.

In an example of panic and illogic that is typical for the Golden State, fears that a plume of radioactivity will cross the Pacific and rain down on California have resulted in a run on iodine tablets. Pharmacies are being inundated with requests for the chemical. I've even heard of some people in Idaho and other regions who are snatching up iodine at drugstores as well as buying it on the Internet.

As I mentioned in a previous post, tablets of stable iodine are taken by those who are exposed to fission products to saturate the thyroid and prevent the absorption of the radioactive isotope of iodine that is produced in a nuclear reactor. However, it won't protect a person from external gamma radiation or the ingestion of other fission products like radioactive strontium or cesium.

So, in the middle of a panic, when state and local officials are trying to calm down the citizens, what does Surgeon General Regina Benjamin say?

State and county officials spent much of Tuesday trying to keep people calm by saying that getting the pills wasn't necessary, but then the United States surgeon general supported the idea as a worthy "precaution."

[...] NBC Bay Area reporter Damian Trujillo asked [U.S. Surgeon General Regina Benjamin] about the run on tablets and Dr. Benjamin said although she wasn't aware of people stocking up, she did not think that would be an overreaction. She said it was right to be prepared.

Dr. Benjamin's response was utterly inappropriate and thoughtless. Instead of backing up Californian officials who correctly insist that such precautions are unnecessary, the Surgeon General has instead given support to baseless worries.

Californians' concerns are unwarranted for several reasons. First, the spread of contamination seems to be relatively limited. This is not like the Chernobyl accident in which the combination of an exploded reactor vessel and burning graphite blew huge amounts of contamination into the air and caused a measurable amount of radioactivity to spread across northern Europe. Even then, although towns near Chernobyl were made uninhabitable, the levels of contamination found in the rest of Europe were relatively harmless. In contrast, the Fukushima reactors are mostly intact and don't contain flammable materials inside their vessels. Second, Japan is over 5,000 miles from California. By the time contamination could reach the West Coast from Japan, the cloud would probably be so widely dispersed that the radioactivity would be effectively undetectable and would have a negligible impact on public health. Third, the radioactive isotope that the pills are designed to protect against (i.e., iodine-131) has a half-life of only 8 days. This means that within 8 days, half of the iodine reaching California would have transformed into a stable form of xenon gas. Since it can take 7 to 9 days for dust in Asia to cross the Pacific Ocean, by the time any contamination actually reached North America much of the iodine-131 would have changed into a harmless substance. The other major fission products, cesium-137 and strontium-90, have longer half-lives (30.2 and 28.9 years, respectively).

After the absurdities of the media, panicky Californians, and the U.S. Surgeon General this past week, I can honestly say that I've seen 1950s b-movies with a better understanding of nuclear energy.