Operation Upshot-Knothole, Nevada Proving Ground, March-June 1953. Projects 23.4-23.14 and 23.16. Genetic Effects of Fast Neutrons from Nuclear Detonations,
Abstract
A series of genetics test objects were exposed to fast-neutron irradiation at Operation Upshot-Knothole. The exposures were made by placing the specimens inside 7-in.-thick lead hemispheres that were first used at Operation Greenhouse. These objects were set at appropriate distances from ground zero to cover the dose ranges required. The genetics test materials were supplied by a number of active investigators at Oak Ridge or at university laboratories and were sent to Mercury in the proper stage for exposure shortly before the scheduled detonations. After exposure the material was returned for breeding and study. Plant materials used included spores of several fungi, Tradescantia pollen, and seeds of Datura and of corn. Drosophila flies, Mormoniella wasps, and several mouse strains constituted the animal specimens used. The data support the following conclusions: (1) The relative biological effectiveness (RBE) for genetic effects from detonation neutrons compared with x or gamma irradiation is high, observed values ranging from about 2 to 15 or more; (2) The RBE for chromosome breakage from detonation neutrons is not significantly higher than that from cyclotron neutrons--this conclusion is subject to some uncertainties in dose determination; (3) It is indicated that the RBE for the production of simple mutations by fast neutrons compard with x-rays tends to be low. The values are higher for gross chromosome aberrations; (4) The genetic tests are of some value as 'biological dosimeters' supplementary to physical dosimetry; and (5) The studies clearly indicate that, for equal doses, Neutrons represent a greater potential genetic hazard than other forms of radiation from nuclear detonations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1954
- Accession Number
- ADA080270
Entities
People
- C. W. Sheppard
- H. H. Plough
Organizations
- United States Atomic Energy Commission