RADIATION

Radiation or ionizing radiation cause mutations and this concern was aroused with the advent of the atomic age. Owing to the difficulty of observing mutation rates in man, almost all the information available has been from extrapolations from animal data. Radiation causes breaks and rearrangements in chromosomes and in DNA, point mutations, base changes, small deletions or frame shifts.

Natural sources of radiation:

Cosmic rays
Background radiation from deposits
Artificial sources
Nuclear test explosions
Nuclear reactor leaks
Nuclear reactor wastes
Diagnostic or therapeutic irradiation
Industrial, occupational and laboratory radiation hazards
Office equipment like, computers and visual display units
Granite floors and walls

Background and cosmic radiation accounts for about 3 rem per generation. Medical uses add another 0.5 to 5 rem. Atomic testing may have contributed about 0.5 rem. These add up to quite a significant sum. In great Britain it has been estimated that for every 3.3 million of exposed population, over a period of 30 years, 320 new genetic cases will appear due to the contributions from the present level of radiation for medical reasons.

In addition to point mutations and chromosome aberrations, radiation is known to cause, leukemia and other forms of neoplasia and breast cancer in women exposed as children to atomic bomb irradiation. Prenatal diagnostic irradiation increases the risk to the unborn child, of leukemia and may be even postnatal cancer. As a general rule, avoidance of any irradiating procedure or source throughout life, particularly during pregnancy is advised.