Tens of thousands of people flock to Austrian mountains every year in search of a controversial form of therapy.

However experts are skeptical over the healing powers of the caves and warned that exposure to radon gas could prove to be dangerous as it increases the risk of lung cancer.
Says Dr Hasan Tahir, a consultant rheumatologist at Whipps Cross University Hospital in East London, “It may be an interesting option for patients to take this treatment alongside conventional medicine. However, as radon is potentially carcinogenic – admittedly at a much higher dose – I would like to see more long-term safety data.”
Source-Medindia