Caesium-137
gamma sources have been involved in several
radiological accidents and incidents.
1987 Goiânia, Goiás, Brazil In the
accident of1987, an improperly disposed of
radiation therapy system from an abandoned clinic in , Brazil, was removed, then cracked to be sold in
junkyards. The glowing
caesium salt was then sold to curious, unaware buyers. This led to four confirmed deaths and several serious injuries from radiation contamination.
1989 Kramatorsk, Ukraine The
1989 Kramatorsk incident happened in1989 when a small capsule in size of caesium-137 was found inside the concrete wall of an apartment building in
Kramatorsk, Ukrainian SSR. It is believed that the capsule, originally a part of a measurement device, was lost in the late1970s and ended up mixed with gravel used to construct the building in1980. Over 9years, twofamilies had lived in the apartment. By the time the capsule was discovered, 6residents of the building had died, 4from
leukemia and 17more receiving varying doses of radiation.
1994 Tammiku, Estonia The
1994 incident involved the theft of
radioactive material from a
nuclear waste storage facility in
Parish,
County,
Estonia. Threebrothers, unaware of the facility's nature, broke into a shed while scavenging for
scrap metal. One of the brothers received a (40
Gy) whole-body dose from a caesium-137 source that had been released from a damaged container, succumbing to
radiation poisoning 12days later.
1997 Georgia In 1997, several
Georgian soldiers suffered radiation poisoning and burns. They were eventually traced back to training sources left abandoned, forgotten, and unlabeled after the
dissolution of the Soviet Union. One was a caesium-137 pellet in a pocket of a shared jacket that released about 130,000times the level of
background radiation at a distance.
1998 Los Barrios, Cádiz, Spain In the
accident of1998, the Spanish recycling company accidentally melted down a mass of radioactive caesium-137 that came from a
gamma-ray generator.
2009 Tongchuan, Shaanxi, China In 2009, a Chinese cement company in ,
Province was demolishing an old, unused
cement plant and did not follow standards for handling radioactive materials. This caused some caesium-137 from a measuring instrument to be included with eight truckloads of
scrap metal on its way to a
steel mill, where the radioactive caesium was melted down into the steel.
2015 University of Tromsø, Norway In March 2015, the Norwegian
Universityof lost 8radioactive samples, including samples of caesium-137,
americium-241, and
strontium-90. The samples were moved out of a secure location to be used for education. When the samples were supposed to be returned, the university was unable to find them. , the samples are still missing.
2016 Helsinki, Finland On March 2016, unusually high levels of caesium-137 were detected in the air in , Finland. According to Finland's
Radiation and Nuclear Safety Authority(STUK), measurements showed approximately 1,000times the usual
background level. A STUK investigation traced the source to a building from which STUK itself and a radioactive waste treatment company operate.
2019 Seattle, Washington, United States Thirteen people were exposed to caesium-137 in May2019 at the Research and Training building in the
Harborview Medical Center complex in
Seattle, Washington. A contract crew was transferring the caesium from the lab to a truck when the powder was spilled. Five people were decontaminated and released, but 8 who were more directly exposed were taken to the hospital while the research building was evacuated.
2023 Western Australia, Australia Public health authorities in
Western Australia issued an emergency alert for a stretch of road measuring about after a capsule containing caesium-137 was lost in transport on 25January 2023. The capsule contained a small quantity of the radioactive material when it disappeared from a truck. The State Government immediately launched a search, with the WADepartment of Health's chief health officer
Andrew Robertson warning an exposed person could expect to receive the equivalent of "about 10
X-rays an hour". Experts warned, if the capsule were found, the public should stay at least away. The capsule was found on 1February 2023.
2023 Prachinburi, Thailand A caesium-137 capsule went missing from a
steam power plant in
province, Thailand on 23February 2023, triggering a search by officials from Thailand's
Office of Atoms for Peace(OAP) and the provincial administration. However, the Thai public was not notified until 14March. On 20March, the Secretary-General of theOAP and the governor of held a press conference stating that they had found caesium-137 contaminated furnace dust at a steel melting plant in
district.
2024 Khabarovsk, Russia On 5April 2024, an emergency regime was introduced in the Russian city of after a local resident accidentally discovered that radiation levels had jumped sharply in one of the industrial areas of the city. According to volunteers of the dosimetric control group, the dosimeter at the NP site showed up to , which is 1600times the safe value. Employees of the Ministry of Emergency Situations fenced off the area to , where they found a capsule with caesium from a
defectoscope. This was placed in a protective container and taken away for disposal. The incident was first reported by the .
2025 Indonesia and United States On 18August 2025, the United States
Food and Drug Administration(FDA) issued a statement indicating that shipments of
shrimp from
Indonesia had been contaminated. This was only the first of several
major recalls of irradiated shrimp processed by the Indonesian company Bahari Makmur Sejati (
BMS Foods). The source of the material was traced to a metal scrapyard in the Modern Cikande industrial estate near Jakarta, in which the company supplying the shipping containers was also based. ==See also==