Trivia

This episode is loosely based on the true events during the Russian campaign in Chechnya where an ex-KGB agent was poisoned and later died from a radioactive material known as Pulonium 210. The ex-agent was poisoned by consuming contaminated sushi.

The "hospital" that the lieutenant is in, is in fact not a hospital but a military research institute. They use the name and the logo of the Armed Forces Radiobiology Research Institute for the hospital where the man exposed to radiation is dying. There is no hospital at the AFRRI, just research labs.

The AFRRI may not have a hospital facility, but in addition to researchers it is also staffed by medical doctors who are specialists in nuclear medicine and are part of the Medical Radiobiology Advisory Team that consults with law enforcement, military and medical personnel in response to nuclear and radiological incidents and they are often directly involved in treating people with radiation sickness as they are some of the world's foremost experts on the subject. AFRRI is located in Bethesda, Maryland only a block away from Walter Reed National Military Medical Center, military personnel exposed to radiation are often treated at Walter Reed by doctors from the AFRRI since it is in close proximity to their lab and Walter Reed has a dedicated biohazard isolation unit especially equipped for treating patients exposed to biological, chemical and radiological agents. This is likely where Lt. Sanders is being treated at.

Tony mentions the movie D.O.A. (1949) when describing a plot of someone being poisoned by radiation. Matthew Marsden, who plays the character who is poisoned in this episode, was in the movie DOA: Dead or Alive (2006).

As Dr. Hass states Prussian blue was originally used as a pigment in dyes, it was the first synthetic pigment made and was discovered in 1706 by a painter from Prussia, hence its name. Experiments done in the 1960's showed that Prussian blue could be used to treat thallium and radioactive cesium poisoning. It works by binding to the cesium and thallium atoms preventing them from being absorbed into the intestines, thereby allowing the toxins to be flushed from the system via urine and feces. Although it is most effective when administered prior to exposure as a preventative measure, as a post-exposure treatment it only effective immediately after exposure; it cannot reverse the damage already done by the cesium or thallium once it has been absorbed by the gut and is not effective when the substance has been absorbed via the skin or lungs.

The agent Lt. Sanders was poisoned with is identified as being a radioactive isotope of thallium. Thallium is a post-transition metal like aluminum, tin and lead; it is also a heavy metal like arsenic, cadmium, chromium, copper, lead & mercury. Thallium is extremely toxic in all forms, it is considered to be the most toxic heavy metal (even more than arsenic), and is informally known as the "poisoner's poison" because it is highly water soluble, is colorless, odorless & tasteless and it kills rapidly with only small amounts. Thallium has several properties that make it highly toxic, it is chemically similar to potassium and therefore is readily absorbed and metabolized through the same pathways potassium is, causing it to be distributed throughout bodily fluids and tissues; making it easily absorbed through the digestive tract, skin and lungs. Thallium interferes with the body's ability to use sulfur to make the amino acid cysteine, which is used in the production of a number of proteins essential to the nervous system. This initially results in peripheral nervous system damage, early symptoms of thallium toxicity are burning sensations in the extremities, hair loss, stomach pain, nausea, vomiting and diarrhea. More serious neurological damage and symptoms appear 2-3 days after exposure and include tremors, headache, insomnia, seizures, uncontrollable muscle movements, ascending loss of sensation, coma, and death if not treated soon enough. Thallium has a number of radioactive isotopes but the only one stable enough to cause poisoning is thallium-204, it is made by exposing thallium to neutrons in a nuclear reactor and is used in certain types of atmospheric gas & dust detectors, it can also be made into thallium-207, which has a half-life of 4.77 minutes, making it useful for imaging in nuclear medicine without being toxic since it degrades so quickly. When used as a poison thallium-204 is probably one of the deadliest and most effective toxins, being radioactive adds to thallium's already extremely toxic properties and would be deadly even in tiny amounts and is almost impossible to treat, by the time physical symptoms appear fatal & irreversible damage has already occurred to the nervous system.