Radiation side effects you must know

Radiation is a subject most of us know very little about, especially radiation side effects.

• What is it?
• What it does?
• Where does it come from?
• Why is it harmful in some cases?

Here's a brief outline. Radiation is a form of energy. All living beings require some kinds of radiation just to live. Light and heat, for example, are two basic forms of radiation necessary for all life on Earth.

There are several different types of radiation. The term "radiation" actually covers a collection of several different types of visible electric and magnetic forces, gases or particles in the air.

These originate from 5 basic sources:

1. outer space
2. the Earth
3. the air we breathe
4. the food and drink we take
5. man-made sources

Radiation is basically classified as follows:

Ionizing and Non-Ionizing Radiation

There are 2 types of radiation, "ionizing" and "non-ionizing", to denote its energy and danger.

Ionizing radiation is radiation with sufficient energy to dislodge electrons from atoms which is the basic building blocks of things. It thus changes the chemical properties of substance it interacts with.

Examples of ionizing radiation are:

• X-rays
• gamma rays
• alpha particles
• beta particles
• and cosmic rays

The term "radioactivity" generally refers to the release of ionizing radiation. More specifically, it is the property of certain unstable elements to change (decay) and emit radiation.

Ionizing radiation may cause damage in living tissue. However, different types of radiation such as alpha, beta, gamma and X-ray differ in their ability to cause tissues damage.

Non-ionizing radiation is radiation without enough energy to ionize the atoms. Examples of this radiation and devices using it are:

• ultraviolet
• visible light
• lasers
• infrare
• microwave
• radio frequency
• extremely low frequency
• acoustic
• and ultrasound

Natural and Artificial Radiation

Radiation can be natural or man-made.

Natural or background radiation
Radioactive material is found throughout nature. It occurs naturally in soil, water, and vegetation. All living things are constantly bombarded by radiation from space known as cosmic radiation. Everyone has radioactive materials inside their bodies from birth.

Artificial or man-made radiation
Radiation can also be produced artificially by humans. For example, X-rays in hospitals are produced electrically without using radioactive substances. The same is true for radio waves that transmit our radio and TV programs through the air.

Useful, but Also Harmful

Radiation can be both useful and harmful.

We see using part of electromagnetic spectrum that our eyes detect as visible light. Radiation is commonly used to diagnose ailments. Some people are treated with artificial radiation to cure disease. For example, medical and dental X-rays check hidden problems.

And a multitude of products that make communication convenient such as telephones and computers, are made possible with radiation.

However, various sicknesses and even death can occur to people exposed to certain levels and types of radiation. Several types of electromagnetic radiation are unwanted and detrimental by-products in electrical and electronic equipment usage.

For example, internationally many early pioneers of medical X-rays suffered loss of limb and life through overexposure.

Radiation side effects on health

Ionizing radiation is known to be carcinogenic, or cancer-causing. Large doses of ionizing radiation exposure, very much larger than background levels, can also cause a measurable increase in cancers and leukemia ("cancer of the blood") in later life.

Animal and plant studies indicate that it can also cause genetic mutations that affect future generations. At very high levels, radiation exposure can cause sickness and death within weeks.

To measure long term radiation exposure risks, experts use a standard unit of measurement called Sieverts, or more commonly thousandths of Sieverts or millisieverts (mSv). These units measure quantities called "equivalent dose to individual tissues" or "effective does to the whole body".

British estimates on radiation side effects

Based on British estimates, long-term fatal cancer risk is estimated to be 5% per Sievert of whole body effective dose. This means that an additional radiation dose of 5 mSv would add an additional 0.025% to a person's, say, 25% risk of dying from cancer. This would make their total cancer death risk 25.025%.

In real terms, radiation expsoure of 1 mSv (British estimates) means:

• Lower levels of psychological well-being which includes depression, anxiety, self-harm and suicide.

• Higher rates of morbidity, for example, debilitating long-term illness.

• Higher rates of premature deaths, especially coronary heart disease, injuries and poisoning, including suicide.

An abdominal CT scan gives a radiation exposure dose of about 10 mSv. This is equivalent to about 4 years of background radiation.

Australian estimates on radiation side effects

Based on Australian estimates:

• 10,000 mSv (10 Sieverts) as a short-term and whole-body exposure would cause immediate illness such as nausea and decreased white blood cell count. It will cause subsequent death within a few weeks.

• 1,000 mSv (1 Sievert) in short-term dose causes immediate radiation sickness. Above 1,000 mSv, the severity of illness increases with dose. If exposure greater than 1,000 mSv occur over a long period, they pose a definite risk of cancer in later years.

• Above about 100 mSv, the probability of cancer increases with dose. The estimated risk of fatal cancer is 5 of every 100 persons exposed to a dose of 1,000 mSv. If the normal incidence of fatal cancer were 25%, this dose would increase it to 30%).

In Australia:

• 50 mSv is the highest expsoure allowed by regulation in any one year of occupational exposure.

• Approximately 2 mSv a year is the typical background radiation from natural sources, including an average of 0.7 mSv per year from radon in air. This is close to the minimum dose received by all humans anywhere on Earth.

• 0.3-0.6 mSv a year is a typical range of dose rates from artificial sources of radiation, mostly medical.