Cesium in pollen not viewed as health risk
The Forestry Agency believes cedar pollen next spring contaminated by cesium fallout from the Fukushima No. 1 nuclear plant will be well below the legal safety limit.
The exposure from inhaling cesium-contaminated cedar pollen circulating from Fukushima Prefecture will have a maximum radiation reading of 0.000132 microsievert per hour, the agency said, based on a recent calculation of fallout affecting cedar needles and leaves.
In June, the education and science ministry studied cedar leaves in the town of Kawamata, located about 45 km from the Fukushima No. 1 nuclear plant, and determined the cesium-134 and -137 levels ranged from 54,300 to 177,600 becquerels per kilogram.
The Forestry Agency used those results to estimate the radiation exposure from pollen grains. If the level of contamination was 177,600 becquerels per kilogram and the concentration of pollen grains — a gauge of pollen density that shows how many grains are floating in 1 cu. meter of air — was 2,207, the exposure would be equal to 0.000132 microsievert per hour.
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