By Laura Zuckerman
SALMON, Idaho, Oct 5 (Reuters) - Smoke from a wildfire inIdaho that burned mining sites with traces of uranium andthorium contained elevated levels of radiation, but none thatposed a risk to human health, state officials said on Friday.
The state Department of Environmental Quality last monthtook air samples in North Fork, a town in the burn zone ineast-central Idaho, after the so-called Mustang Complex fireswept through a former uranium mine and two abandoned goldmines.
Health officials said then they believed risks to people'shealth was low, and the latest findings back up that assessment.Residents in the area had expressed worries about the smoke.
Paul Ritter, health physicist with the state environmentalagency, said in the area of the mining sites, smoke from thefire showed amounts of radiation roughly equivalent to emissionsfrom a fire in 2000 that charred parts of Los Alamos NationalLaboratory, the nuclear weapons design facility in New Mexico.
"The readings are definitely elevated but not out of linewith what has been measured in fires before. It is not a risk,"he said.
Americans are exposed to an estimated 310 millirems ofradiation a year from natural sources, including some rocks andsoils, according to the U.S. Nuclear Regulatory Commission.
An analysis of air samples in North Fork showed residentswould have been exposed to 0.5 millirems of radiation in a30-day period. That compares to a dose of 5 millirems deliveredby a round-trip transcontinental flight, Ritter said.
"Residents certainly weren't in a bad state in terms ofairborne radioactivity," he said.
The Mustang Complex fire has consumed nearly 340,000 acresof canyon lands and pine forests since it was ignited bylightning in late July in the Salmon-Challis National Forest.
Even without a danger from radioactivity, smoke from theblaze has posed a danger to residents, especially the young andthe elderly, because it carries fine soot particles that canworsen existing respiratory or cardiovascular ailments.
The smoke triggered unhealthy air readings for more than amonth in North Fork and Salmon in a pollution event that Idahohealth officials said was unprecedented for its duration andpredicted impacts on human health.
The findings of no significant risk from radiation did notease concerns about exposure for Cindy Hallen, who lives 10miles (16 km) from the former uranium operation.
"There are too many unknowns," she said.
Estimates indicate that Idaho wildfires this year alreadyhave been responsible for more air pollutants being releasedinto the atmosphere than all automobiles and industrial sourcesin the state, Governor C.L. "Butch" Otter said in a statement.
(Editing by Alex Dobuzinskis and Eric Walsh)
Keywords: USA IDAHO/RADIATION