Articles >>

April 29, 2019

Author: Masaharu Tsubokura

Editors: Akihiko Ozaki M.D., Yuki Senoo

69. The exposure dosage determines the adverse health effects of radiation poisoning

 Unstable radioactive substances emit unneeded protons, neutrons, electrons and energy in the form of radiation to stabilize their nuclei.

However, radioactive substances are not able to emit protons, neutrons, electrons randomly, and the type and the number of particles emitted are unique to each substance.  For example, 2 protons and neutrons, 1 electron, or a certain amount of energy are emitted by alpha, beta, and gamma rays, respectively.

As another example, radium and radon, which are naturally-occurring radioactive substances found in hot springs, are known to emit alpha rays.

Potassium, an element found in many foods, emits beta and gamma rays. Furthermore, radioactive cesium emits beta and gamma rays, while strontium emits beta rays.

Regardless of their sources, whether it is naturally occurring or artificial, all radioactive substanc...

April 16, 2019

Author: Masaharu Tsubokura

Editors: Akihiko Ozaki M.D., Yuki Senoo

67. There is no difference between natural and artificial radiation

All materials are composed of small invisible matters called "protons, neutrons, and electrons." When there is an imbalance of their numbers, the substance becomes unstable and is said to be radioactive.

As radioactive substances try to stabilize, they emit unnecessary "protons, neutrons and electrons" or energy out. These emitted unnecessary particles are what is so-called radiation.

Between radioactive form of an element and nonradioactive elements, for example, radioactive potassium and potassium, radioactive iodine and iodine, and radioactive cesium and cesium, the number of neutrons are different and radioactive versions of elements emit radiation due to their instability while nonradioactive versions do not.

The important thing is the radiation emitted from radioactive substances are "proton, neutron, electron" and energy. Therefore, both natural and ar...

April 10, 2019

Author: Masaharu Tsubokura

Editors: Akihiko Ozaki M.D., Yuki Senoo

65. Similar to UV light, the total dose of exposure is a crucial risk factor for radiation-related adverse health outcomes.

Do you know why rainbows have seven colors? Well, to answer this question, we have to first recognize that various kinds of light exist in this world, depending on differences in wavelengths (energy): the color of visible light differs depending on its wavelength. The seven colors in the rainbow (red, orange, yellow, green, blue, indigo and violet) move in different wavelengths.

Human eyes cannot catch all of the wavelengths that exist in the world. Besides visible light, light waves with lower energy (longer wavelengths) are called radio waves and infrared rays, well-known for being produced by fan heaters. In contrast, light waves with higher energy (shorter wavelengths) are called ultraviolet rays; you may be familiar with UV-reducing products. Compared to ultraviolet lights, ionizing radiation (X-r...

April 3, 2019

Author: Masaharu Tsubokura

Editors: Akihiko Ozaki M.D., Yuki Senoo

63. Air dose rates are not consistent

"External exposure" occurs when the body is exposed to radiation originating from an external source. Glass badges and monitoring posts are used to measure the radiation.

The level of external radiation, measured by a device called dosimeters, does not remain the same over time, as radiation is not emitted at a regular pace. The emission of radiation occurs similarly to how sparklers give off sparks. If radioactive substances were sparklers, the fireball would be the nucleus and sparks would be ionizing radiations. In the same way that sparks come off randomly, in different directions, ionizing radiations are emitted inconsistently. Consequently, the levels of detected external radiation fluctuate. Therefore, the external radiation level can be determined by measuring repeatedly or calculating the average value over a fixed period.

Moreover, the measurement for external exposure is also...

Please reload

Please reload