reports on the apathy displayed in the hotspots of a health risk

MAYBE it's because it can't be seen or smelled but, despite a growing body of evidence linking radon with cancer, many people living in areas badly affected by the naturally occurring gas are apparently disinclined to consider the risks.

Yesterday, the Imperial Cancer Research Fund published a new study suggesting that radon could be responsible for as many as one in 20 lung cancer deaths in the UK and warned that smokers are at particular risk. The study was the first comprehensive evaluation of the radon health hazard in Britain and echoed the findings of

previous surveys by the National Radiological Protection Board, the Government's radiation watchdog, and work by US research teams.

Radon is a colourless, odourless gas emitted by the naturally occurring uranium in the earth's crust, and certain geological conditions make some parts of the country more susceptible than others to releases.

Two years ago the NRPB published interim results from a major survey to map radon exposure across the UK. Two main areas in Scotland were highlighted as radon hotspots: Helmsdale in Sutherland, which sits on porous sandstone; and parts of Aberdeenshire where a granite and limestone mix allows the radon to escape more easily. It's understood the NRPB has uncovered a number of other, smaller, radon hotspots in Scotland which will be made public at a later date. Tests in the central belt revealed negligible levels.

In the open air, radon readily disperses, but it can build up in confined, poorly ventilated spaces such as some houses. The NRPB estimates between 2000 and 3000 homes in Scotland have radon levels above the accepted limit of 200 becquerels per cubic metre of air.

But even as scientists expressed concern yesterday at the latest findings, health and local authority officials were wearily recounting how they cannot interest people in high-risk areas.

In 1994, NRPB officials said their campaign to identify homes most at risk was being undermined by public apathy and questioned why people were worried about nuclear power when radon delivered higher doses of radiation to many more people. Two years later, as the map of UK hotspots was made public, the Scottish Office urged people to treat the health risk seriously and to take action of they were at risk.

But Dr Ken Oates, a consultant in public health for Highland Health Board, says they continue to struggle to have the issue treated seriously. ''We would welcome any efforts to raise awareness of radon as an issue because in some areas up here we are having great difficulty interesting the public in it at all,'' he says. ''Along with Highland Council we have highlighted the issue, made leaflets available through GPs, and we have got very

little uptake of people wanting monitors in their houses.''

Tim Williamson, of the National Society for Clean Air, believes many people are put off at the cost of modifying their home to disperse radon and has called for a system of mandatory grants to encourage householders to have the work done.

''The threat from radon has been known about for some time and really these kind of figures we saw from the Imperial Cancer Research Fund should not come as a surprise,'' he says. ''What does concern us is that given the length of time it has been known about, the level of action which has been taken is minimal. It has been left up to individual householders to take action and when remedial measures need to be put in place they do cost a fair amount of money. At the moment when people weigh up what is going to be a long-term problem against, say, getting

double glazing in, they choose the

latter. There should definitely be a mandatory system of grants.''

Dr Martyn Green, of the National Radiological Protection Board, meanwhile, says the process to modify homes is not particularly complex

or costly.

''It does depend a little bit on the house, but there are simple measures you can take to reduce radon which might cost between #300 and #800. The most effective way is to get the radon out from under the house by using a radon sump, which involves digging down the side of the house

and fixing a pipe and a fan which

runs continuously off your electricity supply. That would cost about #20 to #30 a year.''

Dr Green admits that, after warning people of the risks in their area, only about 20% to 30% took follow-up action, but he dismisses suggestions that the Government could do more to address the problem.

''There has been an ongoing programme over the past 10 years to publicise the problem. In Scotland we are still working with the Scottish Office. Once we have written to everybody, every household in the area, and said you are at risk, you should do something about it, there is a limit to how far a Government can go before you start to harass people.''