Radiation sickness is a disease brought on by overexposure to electromagnetic radiation (usually in the high frequency range). You are always surrounded by some amount of radiation from visible light, infrared light, radio waves, etc. However, humans are able to endure low levels of radiation over their lifetime without any obvious effect. Radiation becomes dangerous when you are exposed to large quantities of it (acute radiation sickness) or smaller amounts over a long period of time (chronic radiation sickness).
DNA is a sensitive structure that is found throughout the body and it has been found that radiation can cause mutations in DNA. These mutations result in the body producing different proteins than it would normally, causing cells to behave in abnormal manners. One example of the effect of DNA mutation is cancer, one of the most common causes of death. Cancer is caused when mutated DNA allows cells to multiply in an abnormal manner, possibly destroying organs and other sensitive structures in the body.
Radiation sickness was first noticed during early research by radiation pioneers such as the Curies, Roentgen, Tesla, and Edison. When the X-Ray was discovered, researchers exposed themselves to the radiation for long periods of time and without shielding their organs. Eventually, DNA mutations resulted in hemorrhaging of their skin, leaving very noticeable open sores all over their body and, in some cases, dead limbs.
Thomas Edison, for example, was researching what he called a fluoroscope. The device was not shielded to prevent emission of X-Rays and after some time, Edison noticed that one of his assistants had taken ill as a result. Edison scrapped the project, but his assistant ended up getting his forearms amputated after radiation sickness caused the tissues to die.
During the atomic bombing of Hiroshima, thousands of Japanese were subjected to unprecedented amounts of radiation, resulting in a horrific situation. It is said that more people died from radiation sickness than the actual atomic blast, since the radiation spread throughout the region. Not surprisingly, the people who survived the radiation ended up having badly mutated children since they were being constructed with mutated DNA.
Studies conducted on mice during the 1960s have showed that young children and babies are the most susceptible to severe radiation sickness complications since they are still growing and need pure DNA to ensure that their bodies grow in a normal manner. Once their DNA is mutated, their body grows in strange ways, often resulting in death or disability.
With acute radiation sickness, the amount of radiation is what decides how severe the radiation sickness will be. A dosage of 100 roentgens is sufficient to cause sickness. A dosage of 400 Roentgens will cause death 50% of the time and a dosage of 100,000 rads will cause death within an hour.
Symptoms of radiation sickness do not usually develop immediately, rather over a period of time since it takes time for the mutated DNA to produce enough proteins to make an obvious change in body chemistry and structure. Among the symptoms are nausea, diarrhea, burns, swelling, weakness, dehydration, hemorrhaging, hair loss, ulcers, vomiting blood, bloody feces, and bruising.
Doctors can't do much about radiation sickness since they have no way of repairing the DNA. They can, however, treat the symptoms using medication and basic comfort care. Even if you survive radiation sickness, you will likely die early and experience complications in the future.