Fact-checking Amazon's new season of Bosch
The latest season of Amazon’s detective series Bosch premiered recently on its streaming service, Prime. The season opens with the murder of a medical physicist and the theft of radioactive cesium, with plenty of drama following as the protagonist tries to solve the murder and end the “catastrophic threat to Los Angeles.” The show is a work of fiction, but let’s take a closer look at the depiction of radiation to sort out the scientific facts.
The setup: The series stars Titus Welliver as Los Angeles Police Department detective Harry Bosch and Jamie Hector as his partner, Jerry Edgar. The first episode of the sixth and latest season begins late in the evening at a Los Angeles hospital. We are shown a nervous-looking medical physicist as he walks into a laboratory, the camera dramatically focusing on the radiation sign on the door. No one else is around as the medical physicist clears out the lab’s inventory of what we find out later is cesium. The physicist then walks the material out of the hospital without anyone giving him a second look.

A screenshot showing one of the cesium pins being removed by the medical physicist in the first episode of Bosch. Amazon Prime Video.
The medical physicist drives to a secluded meeting spot, where a masked individual demands the cesium. The medical physicist says that he stashed it nearby and will gladly give it up, but only after the safety of his wife—whom, it is implied, has been kidnapped by the masked man—is guaranteed. The scene cuts away to a new one: Bosch and Edgar arriving at the crime scene, where they learn of the murder and eventually discover the theft of the medical material.
To help understand the science and practices portrayed in Bosch, Nuclear News asked some questions of ANS members Steve Biegalski, chair of the Nuclear and Radiological Engineering and Medical Physics Program at Georgia Tech, and Sam Glover, chief of the Chemical and Biological Monitoring Branch of the National Institute for Occupational Safety and Health.
Some context: The radioactive forms of cesium most commonly used in hospitals (Cs -131 and Cs-137) are produced by neutron irradiation of barium and by the fission of uranium, respectively. Cesium is problematic, because it moves easily through the air; binds strongly to soil, concrete, and metal; and, in the case of Cs-137, has a half-life of around 30 years (Cs-131 has a half-life of only ~9 days). The long half-life of Cs-137 means that hospitals can store the material for extended periods of time, unlike other isotopes that have half-lives of only a couple days. The radioactive cesium isotopes found in hospitals are used most often in blood irradiators or other sterilization systems. Both Cs -131 and Cs-137 seeds can also be used for brachytherapy treatment, where small cesium seeds are inserted directly into a cancerous tumor. Biegalski said, “The problem with high-activity, long-lived isotopes is that they pose a radiation risk for the duration of their use and they must be properly disposed at the end of use.” Other uses of radioactive isotopes in medicine can be found on ANS’s About Nuclear page.

An example of a teletherapy radiation capsule like the one at the center of the Goiania Incident in Brazil. The Goiania capsule was 1.8 inches long with a diameter of 2 inches. The depicted components are A.) an international standard source holder (usually lead), B.) a retaining ring, and C.) a teletherapy "source" composed of D.) two nested stainless steel canisters welded to two E.) stainless steel lids surrounding an F.) internal shield (usually uranium metal or a tungsten alloy) that protects a G.) cylinder of radioactive source material, often but not always cobalt-60. The diameter of the "source" is 30mm..
Before we dig further into the Bosch series, it is interesting to note a real-life incident that happened in Goiania, Brazil. Glover explains that in 1987, a radiation therapy machine was removed from an abandoned hospital. That machine used a lead-and-steel capsule that contained 93 grams of cesium instead of small pins as shown in Bosch. The Goiania Incident resulted in four people dying and dozens of homes being demolished due to contamination from the cesium. It’s not an apples-to-apples comparison to what is depicted in Bosch, but it does provide an example of what could happen when radioactive material is released.
What did the show get right? Bosch never specifies what isotope was stolen, but the most likely explanation is that the rods being removed by the medical physicist in the first episode could contain cesium seeds used for brachytherapy or cesium chloride used for sterilization systems. Biegalski explained that radiation contamination would not occur unless the steel case containing the material were broken or damaged, which was noted by the Federal Bureau of Investigation (FBI) agents in the show. Biegalski said, “If Cs-137 were used by domestic terrorists in a dirty bomb, it would wreak havoc on a major city like Los Angeles because of the panic it would induce and not from radiation.”
There are times when the show discusses radiation dose, like when Bosch and Edgar find the cesium. Edgar’s radiation detector does not go off until they are right next to the cesium. “If the source had high activity,” Biegalski said, “the detector should have been alarming much farther away” than portrayed in the show. Bosch does say, after a quick checkup at the hospital, that the doctors told him he would get more radiation on a flight from Los Angeles to New York—which is very true.

Screenshot of when the cesium pins were discovered by Bosch and Edgar. Amazon Prime Video.
Any exposure to radioactive material is not to be taken lightly, but it takes prolonged exposure to high-activity sources found in hospitals to receive enough dose to get radiation sickness or die. The only casualty from radiation in Boschwas a homeless man who found the canister of cesium. It was discovered that the man was sleeping in his van with the cesium only a few feet away for the handful of days after it went missing from the hospital. Biegalski agreed that the scenario depicted “could theoretically give him a lethal dose without any medical attention.”
What is overdramatized? The opening scene of the first episode sets the tone here. Biegalski confirmed that there is no way a medical physicist would be able to simply walk into a hospital’s lab and remove a source like this. “Any radiation source with high enough activity to cause public risk is protected by multiple layers of security,” Biegalski explained. “There are physical barriers for removal along with alarm systems and video surveillance. It is not possible for someone to just walk out of a facility with such a source without alerting others to this removal.”
Then there are the obligatory comments from FBI agents in the show saying things like any radiation contamination would be “catastrophic” with “mass casualties” and the land would be “unusable for 300 years.” If a radioactive source were dispersed over a city by a terrorist organization, Biegalski said, “the concentrations would be reduced significantly and would not be lethal to the city.” We are never told how much cesium is in the stolen pins, but referring back to the Goiania Incident, 93 grams of cesium chloride was spread around the Brazilian city, and four people died. Any deaths are a tragedy, but “mass casualties” is not a realistic statement.
Biegalski added, “The main impact would be denial of use of the contaminated area”—not very different from what we are dealing with now with the COVID-19 pandemic. Economic activity has been halted since mid-March around most of the United States, and the economic impacts have been devastating for many around the country and the world. This is similar to what would happen if a radioactive source were to be dispersed in a major city—though the effects of a dirty bomb would be less widespread than the current COVID-19 pandemic.
While the FBI agents in the show say that the land wouldn’t be habitable for 300 years, in reality the land would instead be decontaminated, as it was in real life in Brazil. During the remediation process, the contaminated area would not be usable. The decontamination would take a considerable amount of time and would be very expensive. Even after the cleanup, the general public would likely still be afraid to return to the area because radiation is undetectable without a sensitive radiation detector. Fear would have much more impact than the radioactive material itself.
Overall, the Bosch series was fun to watch and has received a lot of positive reviews from fans and critics. Its take on radiation, however, has to be taken with a grain of sodium chloride.
The story was updated to clarify the differences in production of Cs-131 and Cs-137