SCIENCE

Members of the exclusive UPPU Club lived and breathed radiation . . . literally. (War is Boring)

See the club’s group project here.

Teachers, scroll down for a quick list of key resources in our Teachers’ Toolkit.

Discussion Ideas

• The short essay never explains how the exclusive UPPU club got its name. What do you think?
  • Pu is the chemical symbol of the element plutonium. Sound it out.

 

• What was the Manhattan Project?
  • The Manhattan Project was a research project that developed the world’s first nuclear weapons.

 

• What is plutonium?
  • Plutonium is a silvery metal that reacts with many other elements. Its atomic number 94 and its atomic weight is 244. It’s expensive, rare, and powerful stuff.
    • Many grades of plutonium are classified according to their concentration of the isotope Pu-240:
      • “Reactor-grade plutonium” (18%) and “fuel-grade plutonium” (7%-18%) are a key fuels for nuclear power plants.
      • “Weapons-grade plutonium” (less than 7%) was the agent used in the world’s first nuclear weapon, nicknamed the Gadget and detonated as part of the Trinity test in New Mexico in 1945. A near-twin to the Gadget, nicknamed Fat Man, was detonated at Nagasaki, Japan, just weeks later.
      • “Supergrade plutonium” (2%-3%) is used by the U.S. Navy in its nuclear weapons.
    • Another isotope of plutonium, Pu-238, has other uses.
      • Pu-238 powers some pacemakers, although most pacemakers now use lithium.
      • Pu-238 is the generating mechanism (radioisotope thermoelectric generator, ahem) for NASA missions such as Voyager, New Horizons, Apollo, and the Curiosity Mars rover.

 

• OK, so plutonium is awesome. Why is there plutonium in the urine of some scientists who worked on the Manhattan Project?
  • Chemists, metallurgists, and technicians involved in the Manhattan Project routinely worked with and around plutonium. (And most, it should be stressed, were never exposed to high or dangerous doses.)
  • Most UPPU Manhattan Project scientists and engineers were exposed to traceable amounts of plutonium by breathing dust containing the element. According to the good folks at Los Alamos, “Approximately 5% to 25% of inhaled [plutonium] particles are retained by the body. Depending on particle size (the smaller the particle, the higher its risk to be retained) and chemical form (soluble forms are more easily absorbed by the blood), inhaled plutonium will remain lodged in the lung or lymph system, or it will be absorbed by the blood and delivered mainly to the liver or bones.”
  • In other words, in high enough doses, plutonium will settle in your body and be excreted as urine, along with water, salts, and waste products.

 

• Uh, isn’t plutonium poisoning deadly?
  • Yes, radiation poisoning can be deadly. In particular, plutonium accumulates in bone marrow, which makes it incredibly dangerous.
  • Plutonium is also a heavy metal, and all heavy metals (even ones that aren’t radioactive) carry significant health risks.

 

• If radiation poisoning is lethal, why are these scientists still alive?
  • Members of the UPPU club had low-level exposure to plutonium and “the mortality rate for the group is about 50% lower than the national average.” (Note: This does not mean plutonium is good for you!) High-level exposure will likely result in an increased risk for lung cancer, and possibly bone and liver cancer.
  • The radioactive risks of plutonium may have been overstated—it doesn’t work like kryptonite on Superman. According to this fascinating article from Los Alamos Science, “Driven by knowledge of the possible harmful health effects of plutonium, scientists carefully warned the public about them and established procedures to protect the workers in plutonium-processing facilities. In fact, their care was so extreme that many believe it was the scientists themselves who promoted an overstated idea that became well known at the end of the 1940s: ‘Plutonium is the most toxic substance known to man.’”

 

• Should I be worried about exposure to plutonium?
  • Not really. Although tiny, tiny amounts of plutonium exist in nature, it is, by definition, a “rare earth element.” Most plutonium on Earth is radioactive fallout from nuclear testing done in the last century. “From the Trinity Test in 1945 until atmospheric testing was banned in 1963, over 5 tons of plutonium were dispersed in the atmosphere in the form of small particles blown around the globe by the wind.” But this isn’t quite reason to worry:
    • “Most of this plutonium dust fell into the oceans, and approximately 96% of that amount simply sank as sediment onto the ocean floors because plutonium is not readily soluble in seawater. The fact that plutonium dissolves very slowly in water also explains why the plutonium concentration in our oceans is low and will continue to be so.”
    • Minute amounts of plutonium settled in topsoil, although its chemical properties largely prevent it from being absorbed by plants.
  • There are two major—and very rare—ways to join the UPPU club.
    • Intentional exposure. For example:
      • In a shameful incident in U.S. history, the government conducted secret radiation (including plutonium) experiments on uninformed patients—children, soldiers, prisoners.
      • In a shameful incident in corporate history, hundreds of young factory workers—the so-called Radium Girls—were exposed to radioactive (radium) paint making profitable glow-in-the-dark watches.
      • In a shameful incident in Cold War history, former Soviet spy Alexander Litvinenko claimed to have been intentionally poisoned (by polonium) by his former colleagues.
      • Nuclear weapon deployment and testing exposed thousands of people to radiation.
    • Accidental exposure. For example:
      • Manhattan Project scientists Harry K. Daghlian and Louis Slotin (the shirtless scientist in the photo above) both died after criticality accidents at the Los Alamos facility.
      • Accidents involving nuclear weapons have released high levels of radiation into the environment. The so-called Thule Incident, for instance, scattered tons of plutonium and uranium across the Greenland ice sheet as a U.S. bomber carrying four hydrogen bombs (!) crashed. Most contaminated material was recovered and removed to a disposal site in the U.S. (The Savannah River Site in South Carolina.)
      • Some nuclear accidents, such as those at Chernobyl and Fukushima, can release plutonium into the atmosphere. But plutonium is not very volatile, and radioactive cesium, cobalt, uranium, and iodine are usually of much greater concern.

 

• Are any other substances radioactive?
  • Trick question! All elements have radioactive isotopes. Radioactive isotopes (also called radionuclides) have an imbalance of nuclear energy. This imbalance makes them unstable, emitting energy (radiation) as they undergo consistent, predictable radioactive decay.
  • The 38 so-called “radioactive” elements are those that lack any stable isotopes.

 

TEACHERS’ TOOLKIT

War is Boring: The Scientists Who Pee Plutonium

Nat Geo: 1945: Trinity Atomic Bomb Test

United States Nuclear Regulatory Commission: Backgrounder on Plutonium

US Department of Energy: The Manhattan Project

Los Alamos Science: Plutonium and Health: How Great is the Risk?

Wikipedia Featured Article: Trinity (nuclear test)

Wikipedia Featured Article: Manhattan Project

Wikipedia Featured Article: plutonium