September 23, 2009
WHO Cuts Safety Limits On Radioactive Radon
In light of the fact that naturally occurring radioactive gas is responsible for up to 14 percent of lung cancer cases, The World Health Organization has made significant cuts in the safety limits of radon to one-tenth of its current level.
"In view of the latest scientific data, WHO proposes a reference level of 100 becquerels per metric cube to minimize health hazards due to indoor radon exposure," said the UN health agency in a report published this week.
"However, if this level cannot be reached under the prevailing country-specific conditions, the chosen reference level should not exceed 300 becquerels per metric cube," it added.
Becquerel is a unit of measure for radioactivity and reference levels represents the maximum accepted radon concentration in a residential dwelling.
There was WHO report back in 1996 that had fixed the reference level at 1,000 becquerels per cubic meter.
Radon claims tens of thousands of lives each year, making it the second greatest cause of lung cancer after smoking, said the WHO.
"Cancers attributable to radon range from 3 to 14 percent, depending on the average radon concentration in the country concerned and the calculation methods," it said.
The sneaky gas cannot be detected by color, odor, or taste. It is released through the soil or bedrock in some areas with relatively high concentrations of decaying natural uranium. These concentrations can then build up inside of homes, particularly in basements, and can seep in through cracks in floors, porous building materials or drains.
Concentrations of the gas are considerably low outdoors, but it has been known to build up in mines and caves.
Health experts say that indoor radon pollution can be cut by carefully designing and building new homes.
Various European countries such as Britain, France, Ireland, Switzerland, Sweden and Italy have a system for tracking areas that are known to have relatively high concentrations of radon.
The WHO also encourages people to keep their homes aired, especially in winter when radon levels build because of windows being shut to block out the cold.
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