Download
1 / 6
100 likes | 933 Vues
LD 50/30. Purpose. The purpose of this presentation is to define the term LD 50/30 as it relates to nuclear medicine and radiation exposure. Furthermore, I will go beyond its definition into a basic explanation of the term and its application. . Definition.
E N D
Purpose • The purpose of this presentation is to define the term LD 50/30 as it relates to nuclear medicine and radiation exposure. • Furthermore, I will go beyond its definition into a basic explanation of the term and its application.
Definition. • LD 50/30 is the dose of radiation expected to cause death to 50 percent of an exposed population within 30 days. • Typically, the LD 50/30 is in the range from 400 to 450 rem (4 to 5 sieverts) received over a very short period. • In other words, the Ld 50/30 is the mean lethal dose, or the dose that would be lethal to 50 percent of the human population within 30 days after irradiation of x or gamma rays given in a single exposure to the whole body.
Continued… • The mean lethal dose will be considerable higher if only part of the body is irradiated or if the irradiation is spread out over a longer time period, such as one week. The administration of special medical care, including infection control and bone marrow transplants, will also increase the LD 50/30.
Usefulness of LD 50/60. • As humans often survive beyond this thirty day period, the LD 50/60, or the lethal dose required to kill fifty percent of a population in sixty days might be more useful at times. • The LD 50/60 is approximately 250 to 300 rads.
Conclusion. • Even though the timing and manifestation of the signs and symptoms vary among various mammals, most mammals show similar signs and symptoms. The survival time after different doses differs greatly among species. In referring back to the LD 50/30 values for different species, humans appear to be relatively radiosensitive.
