Free radon tests for 17,000 homes in Cornwall
About 17,000 homes in an area of Cornwall believed to be a radon hotspot have been offered tests to detect it.
The homes are in the former Carrick district, in mid Cornwall, where high levels of radon have been found, the Health Protection Agency (HPA) said.
Radon is a natural radioactive gas which is believed to be linked to lung cancer, it added.
The HPA, Cornwall Council and the Cornwall and Isles of Scilly Primary Care Trust are behind the project.
A detector is placed in the home for three months and is them analysed by the HPA.
If a property is found to have high levels of radon, advice will be given to the owners on how it can be reduced.
Radon levels have previously been measured in more than 14,000 homes in the former district, which includes Truro, Falmouth and St Agnes.
The HPA said the average level of radon in those homes was 145 becquerels per cubic metre of air (Bq m-3), which was almost seven times higher than the English average of 21 Bq m-3.
Nationally, long-term exposure to the gas is believed to lead to more than 1,000 lung cancer deaths each year, the agency added.