The toll of dead and missing from Japan’s Fukushima earthquake and tsunami approaches 30,000, and entire towns are rubble. At this point, no one has died from Fukushima’s nuclear radiation, and it is quite possible that no one ever will. But radiation hysteria dominates the world’s front pages and television screens. The anti-nuclear community exults as many countries now consider shutting down or delaying construction of nuclear power plants.
While a through review of nuclear plant safety is important, be careful what you wish for. Replacing the annual electric power output of a typical one gigawatt (GW) nuclear plant will require burning five million tons of coal or its equivalent in natural gas. As much as ten million tons of carbon dioxide will then be released to warm us. In the case of coal, the most available substitute, large quantities of mercury, sulfur, and other elements will also join the atmosphere.
The primary public concern over Fukushima is the continuing release of radioactivity. Our bodies receive an average of 300 millirems of natural radiation per year from radon, cosmic rays, certain foods like bananas(potassium 40) and medical exams. The body repairs cell damage from this and larger amounts, or humanity would not exist. The most radiation exposed persons at Fukushima are some workers inside the plants who got doses in the 15 to 25 rem range.
Immediately after World War II, a joint U.S. and Japanese medical team began a 70-year study of 90,000 survivors of Hiroshima and Nagasaki. Those survivors got radiation doses similar to those received by the most affected workers at Fukushima.Seventy years of studies report that the bomb survivors are living longer on average than the Japanese population as a whole with lower cancer rates. California residents are buying up iodine pills, because Fukushima radiation is being detected on our Pacific Coast. That new radiation is one millionth of the amount that the average American receives annually from those natural sources.
The energy producing fission process shut down in all Fukushima reactors. But the radioactive fission products in the active fuel, and spent fuel in the water pools continue to provide heat from beta decay. This produces about 6 percent of the heat created by the fully operating reactor. Without cooling, the temperatures in the reactor from decay heat will rise indefinitely.Normally, backup cooling is done by circulating water with diesel engines, now damaged by the tsunami.
At Chernobyl, a large steam/hydrogen explosion blew out radioactive graphite and other material from a fissioning reactor. 134 plant and emergency workers received very high radiation doses. 28 of them died within a few months. 19 more died within the next 20 years, though from causes not associated with radiation exposure. They have been parents to 14 children, all normal.
Radiation from Chernobyl spread over several countries. The Feb. 28, 2011 UN Chernobyl update states:
“In the three most affected countries, the only evidence of health effects due to radiation is an increase in thyroid cancer among people exposed as children in 1986. There were more than 6,000 cases reported from 1991 to 2005 in Belarus, Ukraine and Russia. By 2005, 15 of the cases had proven fatal.
Radiation is diluted by distance and time. Media panic after Three Mile Island helped end the growth of nuclear energy in the U.S., leaving us with lots of polluting coal plants. Let’s not lose the benefits from our largest supply of clean electric energy which causes fewer injuries than any other major energy source.
ROLF E. WESTGARD, of St. Paul and Deerwood, is a professional member, Geological Society of America, and a member of the Brainerd Dispatch advisory board.