Man-Made Sources of Radiation

Man-made sources of radiation contribute a small portion of the average annual dose for a person living in Ireland.  

It is mainly found in medicine, which is of beneficial use. In total it contributes 14% of the average annual dose, compared with 86% from naturally occurring radioactivity.

Medical

There are three ways in which radiation is used in medicine:

• X-rays.
• Nuclear medicine.
• Radiotherapy.

X-rays are used to assess injury by taking pictures of the inside of a person's body. Nuclear medicine introduces radioactive material into the body to diagnose and treat disease. In the treatment of cancer, radiotherapy uses radiation to treat the illness. Ionising radiation is essential in modern medicine, the average annual dose of which is 0.30 mSv.

In order to regulate the amount of radiation used, all medicinal exposures must be justified and can only be carried out if sanctioned by a doctor. In some cases people get exposed to more radiation than others, depending on the disease that is being treated.

The doses involved in a chest x-ray can be as low as 0.02 mSv, which poses less risk to health than smoking one cigarette.

Radioactivity all around us

Radioactivity is present in our environment due to other man-made activities that are mostly out of our control.

Nuclear weapons testing: Testing of nuclear weapons represents a small radiation dose onto the ground and into our diet. At the height of testing in the early 1960's radiation was dispersed into the atmosphere on a global scale. This can also be referred to as nuclear fallout. We each receive approximately 0.01 mSv from this source each year.

Chernobyl: The tragic events in 1986 at the nuclear power plant in Chernobyl released substantial quantities of radioactivity. Winds spread the radiation to mainland Europe, and there are small doses in the ground and our diet to this day. The extra radiation dose received in Ireland from Chernobyl fallout during the first year following the incident was estimated at 0.105 mSv. It is estimated that this dose will cause between 5 and 25 extra deaths from cancer in Ireland over the next 70 years.

Sellafield: Waste products released from this nuclear reprocessing plant in England are radioactive. Low doses of radiation from this source can be passed onto humans by consuming fish and shellfish from the Irish Sea.

Fukushima: On March 11th 2011, a magnitude 9.0 earthquake and subsequent tsunami wreaked havoc on the north east coast of Japan, with thousands of people confirmed dead or missing. The earthquake and tsunami disabled the reactor cooling systems at the Fukushima Daiichi nuclear power plant, leading to nuclear radiation leaks and triggering a 30km evacuation zone surrounding the plant. Countries around the world which generate nuclear energy are reassessing their safety protocols in light of the incident.

The average person is exposed to radiation from a variety of other sources. Air travel results in increased exposure to radiation. For example, a return flight from Dublin to New York would deliver a dose of 0.05 mSv. Early television sets were also thought to emit x-rays. There was also a fear that video display units (VDUs) may emit ionising radiation, but testing has proved that this fear was unfounded.