APPLICATIONS OF NUCLEAR TECHNOLOGY

William Hill - ORNL
Ed Slowey - K&S Associates

Food Irradiation

According to the Centers for Disease Control and Prevention, more than 81,000,000 million cases of food-borne illness occur in the US each year resulting in upwards of 10,000 deaths.

The US Department of Agriculture estimates the annual cost of food borne illness to be between $5.6 billion and $22 billion.

Causes of food poisoning are: more animals in smaller areas, and cross- contamination from food handling

Food irradiation causes small harmless molecular changes similar to changes caused by cooking, canning, and freezing.

Food irradiation was first conducted in 1903. Today 500,000,000 tons of food are irradiated/year.

Benefits are: reduces disease, controls insects, extends shelf life, leaves no residue, allows package processing, can be used in place of chemicals and fumigants, and causes no change in temperature.

Some Irradiated Foods:

Spices	- largest use, targets insects;
Flour	- targets insects;
Pork	- targets Trichinella;
Fresh Fruits and Vegetables	- 40% of this harvest spoils, delays ripening; (Irradiated strawberries and mushrooms have shelf lives of three weeks)
Poultry	- targets bacterial contamination such as Salmonella.
Red Meat	- targets Salmonella & E. coli (levels reduced >100,000-fold)
Other products which are Sterilized with Radiation: bandages, milk cartons, & contact lenses.
37 Countries irradiate food using 170 irradiators. US Army and NASA are big users, as are hospitals

Pest Elimination

Male flies are sterilized with radiation and released to breed.

Release rates aim at 50:1 ratios of sterilized males to wild males.

Has resulted in eradication of Tsetse fly in Zanzibar, screwworm in the US, and the Mediterranean Fruit Fly in Florida (California still releasing sterile flies for suppression purposes).

Fig. 4: The decline of total body pottasium with age

Body Composition

Natural potassium exists as 3 Isotopes; K-39,K-40 & K-41. K-40 is radioactive and lasts billions of years.

It is the most essential cation of human cells and concentrates in muscle tissue.

Gamma measuring devices are used to detect the amount of potassium in the body. Declines in total body potassium are indicative of loss of muscle mass.

Radioisotope Generators- plutonium generators have been utilized on 24 NASA missions.

Cassini - $3.4 billion Saturn probe powered by Radioisotope Thermoelectric Generator (RTGs)
Galileo - $1.5 billion Jupiter probe also powered by Radioisotope Thermoelectric Generator

RTG battery consisted of 49.4 pounds of plutonium-238 which provides approx. 580 watts of electricity. Plutonium is clad with iridium (melts @ 4449 F) containing small amounts of tungsten, aluminum, and thorium. It is extremely tough and will prevent release in any worst case shuttle accident (Note: launch of one satellite w/ a plutonium RTG was aborted [blown up] and the RTG was recovered in 300 feet of water. It was undamaged by the abort; was cleaned up and relaunched).

Boron Neutron Capture Therapy (BNCT)

Treatment for Glioblastoma Multiforme, a particularly virulent form of brain cancer.
Technique involves injection of a patient with a boron laced drug (boron is a neutron absorber).
The boron is attached to sugar which preferentially locates in cancerous cells.
The patient is then placed in a thermal neutron beam. The boron absorbs neutrons and changes to lithium and a helium nucleus.
The resultant particles have short ranges (the diameter of a cell) and ionize the cells, thereby destroying them.
Technique being performed at BMRR and MIT with very positive results.
DOE recently signed a lease with BioNeutrics, Inc to utilize an available DOE reactor (Tower Shielding Facility) for this therapy.

Applications for Boron Neutron Capture Therapy (BNCT)

Focus of BNCT development has been for glioblastoma multiform (GBM)

6-800 cases in U.S. each year
Conventional treatments ineffective (surgery, chemo, photon)
Mean survival time of 6-9 months after diagnosis

BNCT appears well suited for GBMs

Appears better than conventioanl treatment (also quality of life)
Several areas of technology improvement seem possible

BNCT is being researched for other forms of cancer

180,000 cases of prostate cancer each year
240,000 cases of lung cancer each year

Boron Neutron Capture Therapy

A binary therapy for treating malignant tumors

Application of boron compounds which selectively concentates in tumore cells
Exposure to neutrons with a suitable energy distribution to minimize damage to normal tissue

Easy in concept - difficult in practice

Pharmacology and biokinetics
Boron distribution (macro and micro)
Microdosimetry and biological effectiveness
Beam spectrum and "purity"
Clinical protocol