A very good commentary by Zion on the issue. I would only add that some medical isotopes come from an assortment of particle accelerators. An example of this is TRIUMF in British Columbia as an adjunct to the University of British Columbia.
The impact of nuclear medicine over the past century has been enormous. It has allowed visualization of the human body interior in ways never imagined in the 19th century or before. Today nuclear medicine avoids the need for an enormous number of procedures in exploratory surgery. It should be noted that one of the greatest scientist of all time, Marie Curie, was heavily involved in nuclear imaging. WW1 was the first time that X-Rays were used for examination of injuries. Curie was very active as a radiologist volunteer with the French army medical services providing X-Ray examinations to wounded soldiers. These first generation X-Ray machines were extremely poor in protection operators from nuclear doses. And the doses were very, very large. Wartime X-Ray exposure may account for most of Marie Curie's lifetime radiation dose and not her laboratory work in radioactive materials.
Marie Curie may be the greatest scientist who ever lived. Her two Nobel Prizes, 1903 for Physics and 1911 for Chemistry, make her the only double winner of a Nobel Prize in two different disciplines. All this and her volunteer medical work in WW1 meant a career that none can match, before or since.
Good point, Colin! I'd add an emphasis: whereas the most common imaging isotope (Technetium-99m) is produced plentifully in reactors, it also has a half-life of about 6 hours, making it difficult to deliver continent-wide while still "hot". This waste can be avoided by installing small, cheap (relative to a reactor) special-purpose proton accelerators in or near hospitals across the continent. Those accelerators can also make other, even more short-lived medical isotopes to reduce the exposure of patients and the public as they wait for days to lose their activity.
I once had a 20-minute radiation infusion scan and was sent home without comment, but when I went to work at TRIUMF I set off all the radiation alarms for 3 days (12 halflives of Tc-99m). The doctors were being sensible, but this calibrates the level of radiation paranoia forced upon TRIUMF by regulatory agencies and the anti-nuclear zealots they fear.
Jess, I agree with you entirely. Your point about the short half-life of Te-99m is very well taken. It is indeed an issue for continent-wide or even nation-wide distribution. In Canada, there are 15 sites, mostly hospitals, scattered across the country. Each site has two to seven linacs doing exactly the things you recommend. I can provide you a link to the list of sites if you wish.
As to radiation alarms, over the years there have been a number of alarms set off at Canada's nuclear power plants because of radiation treatments for various employees. This is why all nuclear power plants have a procedure of requiring a short period of 'cooling off' to allow the residual materials to decay below detection levels. This is possible because all of the isotopes used for imaging have very short half-lives.
It's not really paranoia. All regulators and operators are handcuffed by the obstinacy of ICRP. It's necessary to adapt to the requirements of LNT. Nothing will change until there is large scale reform of the International Commission on Radiological Protection. Despite any evidence to the contrary, ICRP is still standing pat on its guess-work recommendations from 68 years ago. It's as though in more than half a century, nothing has been learned about radiation.
There are als the NDT applications that use Co-60 made in nuclear machines to keep built steel structures safe, including ships and other heavy metal stuff. Oil and Gas platforms? Also used in Radiotherapy machines and the sterilisation facilities used in food processing and medical dressings, etc. Plutonium powered the Voyager exploration vehicle, Pu-238, not fissile but has an energetic decay. I imagine Wade Allison could give you chapter and verse.
PS Much realer science than JSO's. Much respect for transitioning to reality.
RTGs powered by Pu-238 were also used on the Galileo and Cassini-Huygens deep space missions. RTGs had to be used because solar power is not available beyond the orbit of Mars because of low flux density.
Also note that RTGs were the only thing that made the very deep space probes Voyager 1 and Voyager 2 possible. V1 was launched in 1977. It transmitted its last images of the solar system in 1990. V1 left the heliosphere in 2012, becoming the first human object to enter interstellar space. V1 has sufficient remaining power in its RTG batteries to function at its current low power state until 2036.
A similar case is with Voyager 2. Launched in 1977 it too will have sufficient power to function at its current low power levels with nearly all of its scientific equipment turned off until at least 2030.
RTGs using Pu-238 was also used on both Viking Mars landers in the 1970s. V1 remained operational until 1982.
Great piece on nuclear medical use - very interesting and informative.
Thanks!
A very good commentary by Zion on the issue. I would only add that some medical isotopes come from an assortment of particle accelerators. An example of this is TRIUMF in British Columbia as an adjunct to the University of British Columbia.
https://www.triumf.ca/
The impact of nuclear medicine over the past century has been enormous. It has allowed visualization of the human body interior in ways never imagined in the 19th century or before. Today nuclear medicine avoids the need for an enormous number of procedures in exploratory surgery. It should be noted that one of the greatest scientist of all time, Marie Curie, was heavily involved in nuclear imaging. WW1 was the first time that X-Rays were used for examination of injuries. Curie was very active as a radiologist volunteer with the French army medical services providing X-Ray examinations to wounded soldiers. These first generation X-Ray machines were extremely poor in protection operators from nuclear doses. And the doses were very, very large. Wartime X-Ray exposure may account for most of Marie Curie's lifetime radiation dose and not her laboratory work in radioactive materials.
Marie Curie may be the greatest scientist who ever lived. Her two Nobel Prizes, 1903 for Physics and 1911 for Chemistry, make her the only double winner of a Nobel Prize in two different disciplines. All this and her volunteer medical work in WW1 meant a career that none can match, before or since.
Good point, Colin! I'd add an emphasis: whereas the most common imaging isotope (Technetium-99m) is produced plentifully in reactors, it also has a half-life of about 6 hours, making it difficult to deliver continent-wide while still "hot". This waste can be avoided by installing small, cheap (relative to a reactor) special-purpose proton accelerators in or near hospitals across the continent. Those accelerators can also make other, even more short-lived medical isotopes to reduce the exposure of patients and the public as they wait for days to lose their activity.
I once had a 20-minute radiation infusion scan and was sent home without comment, but when I went to work at TRIUMF I set off all the radiation alarms for 3 days (12 halflives of Tc-99m). The doctors were being sensible, but this calibrates the level of radiation paranoia forced upon TRIUMF by regulatory agencies and the anti-nuclear zealots they fear.
Jess, I agree with you entirely. Your point about the short half-life of Te-99m is very well taken. It is indeed an issue for continent-wide or even nation-wide distribution. In Canada, there are 15 sites, mostly hospitals, scattered across the country. Each site has two to seven linacs doing exactly the things you recommend. I can provide you a link to the list of sites if you wish.
As to radiation alarms, over the years there have been a number of alarms set off at Canada's nuclear power plants because of radiation treatments for various employees. This is why all nuclear power plants have a procedure of requiring a short period of 'cooling off' to allow the residual materials to decay below detection levels. This is possible because all of the isotopes used for imaging have very short half-lives.
It's not really paranoia. All regulators and operators are handcuffed by the obstinacy of ICRP. It's necessary to adapt to the requirements of LNT. Nothing will change until there is large scale reform of the International Commission on Radiological Protection. Despite any evidence to the contrary, ICRP is still standing pat on its guess-work recommendations from 68 years ago. It's as though in more than half a century, nothing has been learned about radiation.
Her daughter Irene was also heavily involved in radiology, helping her mother. She received harmful levels of exposure from this.
There are als the NDT applications that use Co-60 made in nuclear machines to keep built steel structures safe, including ships and other heavy metal stuff. Oil and Gas platforms? Also used in Radiotherapy machines and the sterilisation facilities used in food processing and medical dressings, etc. Plutonium powered the Voyager exploration vehicle, Pu-238, not fissile but has an energetic decay. I imagine Wade Allison could give you chapter and verse.
PS Much realer science than JSO's. Much respect for transitioning to reality.
RTGs powered by Pu-238 were also used on the Galileo and Cassini-Huygens deep space missions. RTGs had to be used because solar power is not available beyond the orbit of Mars because of low flux density.
Also note that RTGs were the only thing that made the very deep space probes Voyager 1 and Voyager 2 possible. V1 was launched in 1977. It transmitted its last images of the solar system in 1990. V1 left the heliosphere in 2012, becoming the first human object to enter interstellar space. V1 has sufficient remaining power in its RTG batteries to function at its current low power state until 2036.
A similar case is with Voyager 2. Launched in 1977 it too will have sufficient power to function at its current low power levels with nearly all of its scientific equipment turned off until at least 2030.
RTGs using Pu-238 was also used on both Viking Mars landers in the 1970s. V1 remained operational until 1982.