Side Effects of Radiotherapy or Overexposure to Radiation

The x-rays and radiation from the radioisotopes play a great role in diagnostic procedures and therapy, but the exposure exceeding certain limits do have side effects on our body as elaborated below:

1. Skin Reaction: The maximum permissible dose (MPD) for the skin is 100 rads. When a limited area of the skin receives a dose of a few times of MPD within a few days, that may result in the production of erythema and the reaction may stay for a week. A dose of about 1000 rads may cause tanning of skin and hair fall. A dose in the range of 2000 rads to 3000 rads may cause permanent tanning of skin and hair loss. There is possibility of atrophy of sweat glands and serious ulcers.


2. Radiation Sickness: Even a single exposure of 50 rads or more to the trunk or entire body may cause malaise, nausea, vomiting and diarrhea, collectively called radiation sickness. Some people may not be affected at this dose, however effect may be severe at a whole body exposure at 200 rads.


3. Effects on Blood: A single exposure of 25 to 30 rads to the whole body or to the major bones/bone marrow may result in mid to moderate leucopenia (low count of white blood cells in blood), but recovery is there. A dose of 200 to 500 rads to the spinal marrow may cause leukemia in some cases. Keep in mind that the radiations have accumulated effect.


4. Production of Cataract: Excessive exposure of eyes to radiations with an accumulated dose of 100 to 200 rads could impair our vision and cause cataract.


5. Production of Sterility: Even a shorter time exposure to the radiations around 500 rads to the genital organs may cause permanent sterility in either sex. A long term exposure to lesser dose of radiations may also lead to secondary infertility in either sex.


6. Exposure during Pregnancy: Although there are a number of cases receiving radiotherapy for pelvic cancer during pregnancy and delivering normal babies, but a pregnant woman receiving a very large dose of radiation in order of 1000 rads within a few weeks may have a miscarriage or still birth. The possible effect on the fetus may vary with the period of gestation. Congenital abnormalities may affect the babies so pregnancy should be avoided during radiotherapy of pelvic cancer.


7. Genetic Hazards: Irradiation of ovaries or testicles may lead to mutations in genes and affect reproduction. Greater is the exposure, the greater are the chances of genetic abnormalities.