The present nuclear leakage crisis from Japan is a topic to be discussed in present public health. In radiology, the leaked radioactive elements are considered hazard. Here, the author briefly reviews and discusses on two important radio-hazard elements in post nuclear power plant crisis, radioactive iodine and radioactive cesium. Based on previous similar nuclear crisis in Russia, it is evidenced that the increased incidence of some cancers in post-crisis period is due to exposure to these two important radioactive elements.

Background and Aim: Saghand area is located at 190 Km north-east of the Yazd city. The presence of radioactive materials and the possibility of radiation caused concern among people. This study was performed to measure radioactive materials in the soil, plant, and water of the Saghand area. Methods: In a cross sectional and analytical study the amounts of Ra226,Tu232, K40 and Cs137 in each 5Km as far as 50Km of Saghand mines were measured. Samples of plants were washed, dried and grinded. Samples of soil were picked up from 30cm deep and the water samples were picked up from the springs of that area. The samples were analyzed by spectrometry by the pure germanium (H.P.Ge) detectors in the lab of Iran Atomic Energy Organization. Results: The results showed that the value of Ra in the soil was 21-45, Tu was 21-43, K was 303-505, Cs was 0.1-12 Bq/Kg, and the amounts in the both axes were similar. The amount of Ra in the plant of that area was 0.6-2.8, Tu was 1.7-3.3, K was 86-157, and Cs was 0.4-3.4 Bq/Kg. The value of Ra226 of water was between 2 to 8 mBq/liter in the water sources of that area. Conclusion: According to the radiation law, by increasing the distance, the value of radiation from radioactive materials do not decrease. The value of radiation in water was much less than the standard level (110 mBq/liter). Therefore, we can confie to all of the people in the district that the life is not dangerous for water, food and soil pollution with radioactive materials in this region.

Distinguishing naturally occurring radioactive (e. g. ceramics, fertilizers, etc. ) from unauthorized materials (e. g. high enriched uranium, Pu-239, etc. ) to reduce false alarms is a prominent characteristic of radiation monitoring port. By employing the energy windowing method for the spectrum correspond to the simulation of a plastic scintillator detector using the MCNPX Monte Carlo code together with an artificial neural network, the present work proposes a method for distinguishing naturally occurring materials and K-40 from four unauthorized sources including high enriched uranium and Pu-239 (as special nuclear materials), Cs-137 (as an example of dirty bombs), and depleted uranium.