North-West at risk from cancer-causing radon gas

Date released: Jul 13 2009

RPII urges householders in Mayo and Sligo to test for radon.

The Radiological Protection Institute of Ireland (RPII) has found three homes in Mayo and Sligo with concentrations of radon gas up to 16 times the acceptable level. Nationally, radon is responsible for up to 200 lung cancer deaths per year. The RPII believes it is very likely that there are more homes in the North-West with similarly high radon levels and urges local people to test for the gas and reduce their risk of lung cancer. 

The three homes, one of which is located in Claremorris, Co Mayo, and two in Tubercurry and Ballymote in Co Sligo, had measurements of 3261 becquerels of radon per cubic metre (Bq/m3), 2923 Bq/m3 and 2871 Bq/m3 respectively. At these radon levels, the radiation dose to the householder would be equivalent to receiving between 2700 and 4000 chest X-rays per year. 

Commenting on these measurements, Mr. David Fenton, Manager of Radon Advice at the RPII said: “Radon has no smell, taste or colour and, because of this, people cannot tell if they have radon in their home without measuring for it. To date we have measured over 4300 homes in Mayo and Sligo and found that roughly 1 in 6 homes are above the acceptable level. We believe that there are many more homes in these counties with high radon levels. People living in these homes are at increased risk of developing lung cancer.” 

The high levels were found as a result of research into the possibility of reducing the normal three-month radon measurement to a one-month screening measurement without losing accuracy in the result. Householders who had made measurements in the past were contacted to participate in the project and radon measurements are being carried out in 130 homes in Mayo and Sligo. This was part of a national study of 554 homes nationwide. The three householders with very high radon concentrations were identified among this group. As part of a further initiative, earlier this month the RPII issued Guidance for local authorities on the implementation of a radon measurement programme in social housing. The Guidance Document offers advice to local authorities on minimising radon levels in their housing stock and can be downloaded from the website

“We are very concerned about the risks from exposure to radon and counties Mayo and Sligo are known High Radon Areas. The more we measure in these areas, the more high levels we find. Measuring for radon and, in the event of a high reading, reducing the levels present are both relatively inexpensive. We strongly urge people to measure both their homes and workplaces for radon immediately” continued Mr. Fenton.   

The RPII has redeveloped the website so that anyone can now search for their address on an interactive radon map to see whether their home or workplace is in an area predicted to have high radon levels. They can find out what they need to know about radon – what it is, why it is a problem and how they can have a measurement made. Information can also be obtained on freefone 1800 300 600.   


Note to Editors: 

In the interest of confidentiality, the identification and exact location of homes will not be made available.   

Radon is the second biggest cause of lung cancer in Ireland – causing up to 200 deaths per year. Over 100,000 homes and workplaces throughout Ireland are thought to have radon levels above the acceptable limit.   

Radon is a naturally occurring radioactive gas that originates from the decay of uranium in rocks and soils. It has no smell, colour or taste and can only be detected using special detectors. Outdoors radon quickly dilutes to harmless concentrations, but when it enters an enclosed space, such as a house or other building, it can accumulate to unacceptably high concentrations. This gives rise to a radiation dose, which may cause lung cancer.   

The national Reference Level for radon in homes is 200 becquerels per cubic metre (Bq/m3). The Becquerel is the unit of radioactivity.   

To test for radon, one radon detector is placed in a bedroom and a second in a living room for a three-month period. The detectors are small and can be sent and returned by post for analysis. The RPII and a number of private companies provide a radon measurement service. The cost of a measurement is between €40 and €80.   

Radon is a Class-1 carcinogen. Long-term exposure to radon increases the risk of lung cancer. Based on current knowledge, it is estimated that in Ireland, for the population as a whole, a lifetime exposure (i.e. 70 years) to radon in the home at the Reference Level of 200 Bq/m3 carries a risk of about 1 in 50 of contracting fatal lung cancer. This is approximately twice the risk of death in a road accident. Radon is linked to approximately 200 lung cancer deaths in Ireland every year. For people who smoke, or who have smoked, the risk from radon is considerably greater than for people who never smoked.   

Indoor radon concentrations can vary considerably from day to day due to changes in weather conditions, ventilation rates, etc. and for this reason the current recommended measurement period is not less than three months. The RPII are carrying out research to see if this period can be reduced to one month.