ENVIRONMENT

Ionizing radiations have as their main characteristic that they cause ionization of matter and create ions through the detachment of electrons from its atoms. The origin of ionizing radiation can be natural or anthropogenic. The first category includes environmental radiation (soil, air, water, food) as well as cosmic radiation, while the second mainly includes radiation from medical devices, nuclear reactors, nuclear waste, nuclear weapons testing, and construction materials. In the above cases, ionizing radiations are emitted, the category of which includes high-frequency X-rays and γ-rays, the particle radiations of Helium nuclei (α particles), electrons (β particles), protons and neutrons, as well as cosmic radiation. Almost all of these radiations are produced during the manifestation of the phenomenon of radioactivity.

The active or equivalent dose (in Sv-Sieverts), measures the effect of radioactive radiation on the human body after taking into account the type of radioactivity (e.g. β particles, γ radiation, X, etc.) and the energy absorbed by the human body . Another unit of radiation dose used is the rem (rem) where 1 rem = 0.01 Sv.

As an example, we list common causes of elevated radioactivity values:

• Building materials with a high percentage of radioactive materials (e.g. various ceramic tiles, granite countertops, bricks, cement, pumice stone, volcanic ash stones, phosphogypsum, etc.)
• Food with radioactive residue (eg vegetables, milk, meat and fish from the radioactively affected areas in Japan and neighboring areas - anything produced after March 12, 2011).

Ionizing radiations have as their main characteristic that they cause ionization of matter and create ions through the detachment of electrons from its atoms. The origin of ionizing radiation can be natural or anthropogenic. The first category includes environmental radiation (soil, air, water, food) as well as cosmic radiation, while the second mainly includes radiation from medical devices, nuclear reactors, nuclear waste, nuclear weapons testing, and construction materials. In the above cases, ionizing radiations are emitted, the category of which includes high-frequency X-rays and γ-rays, the particle radiations of Helium nuclei (α particles), electrons (β particles), protons and neutrons, as well as cosmic radiation. Almost all of these radiations are produced during the manifestation of the phenomenon of radioactivity.

The active or equivalent dose (in Sv-Sieverts), measures the effect of radioactive radiation on the human body after taking into account the type of radioactivity (e.g. β particles, γ radiation, X, etc.) and the energy absorbed by the human body . Another unit of radiation dose used is the rem (rem) where 1 rem = 0.01 Sv.

As an example, we list common causes of elevated radioactivity values:

• Building materials with a high percentage of radioactive materials (e.g. various ceramic tiles, granite countertops, bricks, cement, pumice stone, volcanic ash stones, phosphogypsum, etc.)
• Food with radioactive residue (eg vegetables, milk, meat and fish from the radioactively affected areas in Japan and neighboring areas - anything produced after March 12, 2011).

Normal values of radioactivity in the environment are generally <0.3 µSv/h (e.g. 0.13 µSv/h is a global average for exposure to natural sources of radioactivity - excluding radon [4] and values greater than 0.4 µSv /h trigger an alarm in Finland).

The exposure limits set by the legislation are as follows:

• Greek and European occupational exposure limit: 10 μSv/h (20 mSv/year - 2000 working hours per year) [5]
• Greek occupationally exposed limit during pregnancy: 0.70 μSv/h (1 mSv/year – 1440 working hours in 9 months)
• Greek general population limit: 0.11 µSv/h (1 mSv/year) Caution: doses due to medical applications, radionuclides in the subsoil, the human body, cosmic radiation at sea level or radon are not included.

Potential health effects depending on radiation dose rate [6]

• 100 µSv/h: increased chance of disease
• 100,000 µSv/h: nausea, vomiting (radiation sickness)
• 1,000,000 µSv/h: increased chance of cancer
• 10,000,000 µSv/h: organ damage and death within hours

The American Nuclear Regulatory Commission (NRC) characterizes as highly radioactive areas in a nuclear power plant or after a nuclear accident when they exceed 1000 µSv/h [7].