Q: My three-year-old daughter had two full body x-rays without any protection. Is sterilisation possible with two x-rays?

A:Even though there is a mild or remote risk of adverse effects, the advantages of diagnostic radiological studies far outweigh the reported adverse effects. The radiation doses used in routine diagnostic radiological procedures are indeed very small so that adverse genetic effects normally do not come into effect. The reported somatic effects include development of subsequent malignancies, cataracts, and rarely loss of fertility especially in boys. Therapeutic doses of radiation can produce anaemia, hair loss, skin burns and lung fibrosis. Exposure to a radiation of 1 mSv carries a risk of cancer 70/million (0.007%). This has to be compared with the usual radiation of 0.04 mSv during a chest x-ray, 1.5 mSv with x-ray of abdomen and less than 2 mSv with a whole body x-ray. Thus, the probability of developing infertility from the procedure is very small.