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Discoveries of the bactericidal properties of radiation
Early 1900's
■ 1905 – Musser and Edsall at the University of Pennsylvania used x-rays to treat pneumonia. Similar studies done by:
- Quimby and Quimby in the 1910’s
- Heidenhain and Fried in 1924
■ 1920’s – Antoine Lacassagne (pictured) pioneered early cellular radiobiology with his research into cancer treatment using radiation -
Studies published on the biological effect of x-rays on bacteriophage.
■ Fernand Holweck (pictured), Salvador Luria, and E. Wollman
■ Concluded that a single ionization suffices to inactivate a small phage particle.
■ Determined that to be effective it must be produced in a more radiosensitive region; the genetic material (AKA the DNA)
■ Macromolecular viruses can be inactivated by an ionization anywhere in the virus -
1954 – First use of medical device sterilization by Ethicon Inc, subsidiary of Johnson & Johnson
■Used to produce sterile sutures
■First used a 2 MeV 0.5 kW Van de Graaff electron accelerator
■1957 switched to 7MeV 5kW electron beam -
First commercial food irradiation plant
■Located in Stuttgart, Germany
■Processed spices for preservation and disinfection
■Also used to kill insect infestations in grain -
Johnson & Johnson's first gamma irradiator
■ Constructed by H.S. Marsh Ltd. for Johnson's Ethical Plastics
■ Located in Slough, England
■ World’s first commercial irradiation plant for the sterilization of disposable plastic syringes
■ Given the Queen’s Award for innovation in sterilization of surgical materials by irradiation.
■ Johnson & Johnson then became not only the first enterprise in history to sell sterile medical products but the first to commercially use ionizing radiation as a sterilization process. -
The Central Tissue Bank starts routinely using ionizing radiation to sterilize connective tissue grafts
■ Medical University of Warsaw, Poland
such as bone, cartilage, tendons, ligaments, sclera, pericardium, skin, acellular dermis and amnion
■ Irradiated with a dose of 35 kGy in a 60Co source
■ Sometimes in junction with a beam of 10 MeV electrons from a linear accelerator -
FDA authorized the first use of irradiation to treat food in the United States
■ Wheat and wheat flour were irradiated to rid them of insects
■ Utilized an electron beam – the result of collaborative research between ARS and the U.S. Army
■ Clearance given for sterilization of can-packed bacon -
International Project on Food Irradiation (IFIP)
■ Sponsored by the International Atomic Energy Agency (IAEA) in Vienna and the Food and Agriculture Organization (FAO) in Rome
■ Consists of a group of 19 countries (eventually 24) researched the consumption of irradiated foods in animals
■ Concluded that the irradiation of any food up to an overall average dose of 10 kGy presents no toxicological hazard -
“Wholesomeness of Irradiated Foods”
■ Published by World Health Organization
■ Concluded that while irradiation does not eliminate all risk from microbial contamination, the foods are wholesome and safe for consumption in humans
■ Also stated no further toxicological or nutritional research is needed on foods irradiated up to an overall dose of 10 kGy.
■ FDA admitted the dose of 30 kGy for the radiation treatment of spices and food products consumed in small amounts -
Prevalence of medical supply sterilization by radiation in Japan
■ Medical products sterilized in Japan in 1999 was estimated to be 600 000 m3, of which about 51% was sterilized by gamma rays
■ 60% of the products were sterilized by radiation (either by gamma rays or e-beam)
■ Overall The sales amounts of sterilized medical products in Japan were 473 billion yen -
United States mail irradiation
■ September 18, 2001 -OCTOBER 2001 - Anthrax attacks
■ The USPS began to irradiate mail to kill anthrax spores in November 2001
■ Radiated mail sent to Congress, the White House, and D.C. federal mail (ZIP Codes 20201-20597)
■ Irradiation systems from Titan Scan (Surebeam) – up to 10 Mega ElectronVolt (MeV) electron beams or up to 7.5 MeV X-ray beams -
Current day medical sterilization standards
■ ISO 11737
■ The international standard governing the sterilization of healthcare products using radiation
■ Part 1 – Outlines requirements for developing, validating, and controlling the radiation sterilization (including Cobalt 60 and Cesium 137)
■ Part 2 – Determines the use of 25 or 15 kiloGrays (kGy) for the minimum sterilization dose
■ Part 3 – Sets requirements of dosimetry and its role in developing, validating, and controlling the process