User:Funny648/Ciudad juarez cobalt-60

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Funny648/Ciudad juarez cobalt-60
Date6 Dicember 1983
LocationCiudad Juárez, Chihuahua, Mexico
Typeradiation accident
CausePrying open of a radiation therapy unit
Non-fatal injuriesAt least 200 exposed over 1 rem

Ciudad Juárez Cobalt-60 Accident (Spanish: Incidente del Cobalto-60)[1] was a radiation accident that occurred on 6 December 1983 in Ciudad Juárez, Mexico.[2] Known as the worst incident involving radioactive material in North America,[3] it involved the unknowing exposure of multiple people to radiation over eight weeks, at least 200 individuals by some estimates.[2]

Background[edit]

Radiation is the disintegration of an atom's nucleus.

Cobalt-60 is an isotope of Cobalt with a half-life of 5 years.[4] This type of Cobalt has more mass than the usual variety of Cobalt (Cobalt-59). Its atomic nucleus is also unstable (radioactive), and in enough amounts, the amount of Cobalt-60 will diminish by half every 5 years.

A curie measures how much a substance breaks apart (radiates) in a given period of time.[5] It is equivalent to 3.7×1010 decays a second or Becquerels (Bq), the SI unit for the same concept.[6]

A rem measures the amount of damage an organism receives as a result of being exposed to radiation; this varies on what organs the radiation went through.[7] It is equivalent to 1 centisieverts (cSv), also an SI unit.[6]

Events Leading Up to Accident[edit]

In 1977, a Lubbock hospital in Texas sold a Picker 3000 radiation therapy unit to an x-ray company in Ft. Worth, Texas. Said company then sold it to a clinic in Ciudad Juárez. The clinic, however, did not have the proper paperwork to handle radioactive materials.[8]

It is believed that this specific Picker 3000 unit had been produced around 1963 and that the supply of Cobalt-60 involved was from September 1969.[3]

Once in Juárez, however, the unit sat idle since the clinic was never able to repair the device.[8]

Accident[edit]

Then, on 6 December 1983, one of the clinic's electricians decided to sell the unit to a junkyard.[1] He and a coworker placed it at the back of a pick-up truck and pryed it open. The unit contained 6,010 pellet, some of which were lost en route to the junkyard.[2]
Once on site, the pellets were mixed with other metals. Those pellets had the same amount of radiation (curies) of 300 grams of radium. This metal found its way to two foundaries, one producing table legs for restaurants, the other steel rods. 600 tons of such steel rods made their way into the U.S. between December 1983 and January 1984. Meanwhile, the electrician's truck sat in a parking lot, where children played frequently.[8]

Detection[edit]

On 17 January 1984, a truck containing (some of) the radioactive steel rods set off alarms at the Los Alamos facility in New Mexico. The junkyard that contained the pellets was then closed four days later.[2]

Clean-Up Efforts[edit]

It took two months to clean up the junkyard and to recover the metal used in the tables and steel rods. The truck, however, had not been buried and was in a fenced area. Well into 1984, the radiation coming from the truck could still be detected across the Rio Grande.[3]
Since the pellets had scatted into a variety of places between Juarez and Chihuahua City, there were twenty-two active sites, some of which were on highway asphalt.[8]

Aftermath[edit]

The contaminated steel rods went on to contaminate 17 out of 35 states in Mexico.[9]

See Also[edit]

Other incidents involving Cobalt-60

Notes[edit]

References[edit]

  1. ^ a b Barragán, Almudena (5 June 2019). "Ciudad Juárez, el mayor accidente nuclear de América". El Pais (in Spanish). Retrieved 29 July 2020.
  2. ^ a b c d "El Cobalto". Window on State Government. Texas Comptroller of Public Accounts. Archived from the original on 14 March 2008.
  3. ^ a b c Marshal, E (16 March 1984). "Juarez: an unprecedented radiation accident". Science. 223 (4641): 1152–1154. doi:10.1126/science.6701516.
  4. ^ "ICRP Publication 107: Nuclear Decay Data for Dosimetric Calculations". Annals of the ICRP. 38 (3): 1–96. 2008. Retrieved 30 July 2020.
  5. ^ "Radiation Terms and Units". Environmental Protection Agency. 12 August 2019.{{cite web}}: CS1 maint: url-status (link)
  6. ^ a b Thompson, Ambler; Taylor, Barry N. (March 2008). "Guide for the Use of the International System of Units (SI)" (PDF). National Institute of Standards and Technology. 811.
  7. ^ "Dose, absorbed". United States Nuclear Regulatory Commission. 26 June 2020.{{cite web}}: CS1 maint: url-status (link)
  8. ^ a b c d Blakeslee, Sandra (1 May 1984). "Nuclear Spill at Juarez Looms as One of Worst". The New York Times. Retrieved 30 July 2020.
  9. ^ Brooks, Dario (25 Oct 2020). "El "Chernóbil mexicano": cómo ocurrió el mayor incidente nuclear de la historia de América". BBC Mundo.{{cite web}}: CS1 maint: url-status (link)

External links[edit]

Category:1983 in Mexico