Radon may be the cause of 300 deaths yearly in Denmark.

Hundreds of people die from cancer induced by overexposure to the dangerous gas radon, research suggests More than 755,000 people nationwide are exposed to excessive levels of cancer-causing agent radon, according to figures from the National Institute of Radiation Protection’s…
Radon is a naturally occurring gas that comes primarily from ore and its density means it can easily accumulate in buildings. The Health Board estimates that more than 300 deaths each year can be attributed to radon poisoning.

The World Health Organisation (WHO) lowered its recommendations for acceptable radon levels earlier this year to 100 Becquerel units per square metre, after research determined the gas was more dangerous than previously thought.
Lene Espersen, the business and economy minister, reported to parliament that up to 350,000 buildings and homes across the country are believed to contain excessive radon levels. She has asked the Danish Enterprise and Construction Authority to follow the new WHO recommendations.

Presently, radon levels in Danish buildings are recommended to be at highest 200 bq/sqm. But that is only a recommendation and not the law, and there are currently no legal limits for how much radon can be present in buildings.
Mette Neerup, head of the environmental division of engineering firm Niras, said Denmark needed a national radon plan like the one introduced in Sweden.

‘It’s a weak political action when the only thing the minister does is to revise a recommendation,’ she told trade publication Ingeniøren. ‘If we don’t set stricter requirements then nothing will change.’

Areas in Denmark where buildings have the highest radon levels include southern Funen, western Lolland, Møn and Bornholm.