PALOMARES , Spain -- Almost 40 years have passed since the U.S. Air Force accidentally dropped four hydrogen bombs on Spain. But the fallout continues with a newly published scientific study that traced the spread of radiation from the accident site -- and continuing rumors about a mysterious fifth bomb that supposedly is still leaking on the Mediterranean Sea floor. Ironically, while the scientists who conducted the study discount the fifth-bomb theory, their findings have fueled the rumors. They reported that the Mediterranean, indeed, has been contaminated -- but only from radioactive material that washed into the sea from the bombs that hit land. They also said current levels of radioactivity pose no threat to people. The story goes back to Jan. 17, 1966, when a B-52 bomber and a KC-135 tanker aircraft collided during a refueling exercise over the sleepy farming village of Palomares on Spain's southeastern coast. Both planes disintegrated and down went the B-52's four hydrogen bombs, creating the first U.S. nuclear weapons crisis near a populated area. Each 1.5-megaton bomb packed 100 times more explosive power than the bomb dropped on Hiroshima in World War II. Two were found intact. One fell on land, the other into the Mediterranean, where it was recovered after an 80-day effort dramatized in the 2000 Hollywood film "Men of Honor." The movie spotlighted U.S. Navy diver Carl Brashear, who lost a leg in the effort. Non-nuclear explosives in the other two bombs detonated when they hit the ground. Hydrogen bombs contain conventional explosives that trigger the nuclear blast. Seven pounds of plutonium were splattered over 558 acres of Palomares, forcing an $80 million clean-up by the United States. Military crews hauled away 1,500 tons of radioactive soil and tomato plants for burial at a nuclear waste dump in Aiken, S.C. Some radioactive material inevitably was left behind, perhaps as much as 15 percent of the total. "The remainder of the original plutonium clearly has spread, and spread widely," said William R. Schell, a University of Pittsburgh emeritus professor and a member of the international team that reported on the accident in the current edition of the journal Science and the Total Environment. "There's been quite a bit of migration into the Mediterranean." Radioactivity was detected in western Mediterranean plankton -- tiny plants and animals that drift in the water and serve as staple food for fish and other larger organisms. "It was a surprise," said Joan-Albert Sanchez-Cabeza of the University of Barcelona, head of the research team. Sanchez-Cabeza explained that plutonium does not dissolve easily in water. Yet somehow, plutonium and a related radioactive material, americium, got into the water and were taken up by marine organisms. Plutonium is extremely toxic and lingers in the environment for ages. It takes 24,000 years for half of a given amount to decay. Plutonium outside the body is relatively harmless because it emits a form of radiation that cannot penetrate skin. But when absorbed into the body from air, food or cuts in the skin, it can cause cancer and other serious health problems. The research team found that the highest radiation levels in the plankton were well below the human danger level set by the World Health Organization. It also learned that the plutonium apparently does not accumulate to higher levels in the fish that eat plankton -- a matter of particular concern to the Spanish, who eat a lot of fish. "We think that the plutonium found in plankton should not be of serious concern to the public," Sanchez-Cabeza said. "But further research and monitoring is needed." The study revived rumors that a fifth nuclear bomb from the Palomares accident was never recovered and remains submerged in the Mediterranean, leaking radiation. A Spanish radio news program dredged up the old stories right after the new study was announced. "That has been a local rumor or worry in the area since the accident," the station's commentator noted. "Well now, the latest radioactive readings in local plankton have started to rise. I'll leave you to decide for yourselves if there is another bomb." Sanchez-Cabeza, noting the lack of any documentation to support the fifth-bomb theory, said, "Well, that's a big one." American B-52 bombers in the 1960s typically carried four hydrogen bombs. In another of more than 30 known "Broken Arrow" incidents between 1950 and 1980, a nuclear-armed B-52 crashed near the Thule Air Base in Greenland in 1968. Crews recovered four nuclear bombs. Researchers dismiss the fifth-nuke stories and believe that contaminated soil from Palomares eventually washed into the ocean after heavy rains. Wind-blown dust, which contains the same chemical "fingerprint" as the radiation found in the soil at Palomares, may be another source. The U.S. Department of Energy and its Spanish counterpart are monitoring the health of Palomares' 1,500 residents. The Energy Department said the accident so far has caused no known radiation-related cancers or other health problems. In 2002, the U.S. Air Force surgeon general re-analyzed the radiation exposure of 1,500 U.S. military veterans involved in the Palomares clean up. Their work involved packing contaminated soil in steel drums, burning tainted crops and roto-tilling fields to bury radioactive material. The surgeon general concluded that they were exposed to only one-tenth the current radiation limit for workers at commercial nuclear power plants and other facilities. The Air Force study reached similar conclusions for 700 personnel involved in cleaning up the Broken Arrow incident in Greenland, which happened when a B-52 caught fire and the crew was forced to bail out. Conventional explosives in the hydrogen bombs detonated in that incident as well, spreading plutonium and other radioactive material over the ice and snow. In his 1997 book "America's Lost H-Bomb," the late Randall C. Maydew, a government nuclear weapons guru who helped design arming, fusing, firing and safety systems, wrote that the Palomares case and other Broken Arrow episodes produced at least some beneficial fallout: They prompted designers to make weapons less prone to release radioactive material in the case of an accident. _____ Yvonne Zanos, KDKA-TV consumer editor, can be reached at 412-575-2234 or <mailto:zanos@kdka.com>zanos@kdka.com. Please provide your name, address and daytime telephone number with all inquiries. She tries to reply to all inquiries but, because of the volume of questions she receives, she cannot always respond.) She also can be reached by writing to her c/o KDKA-TV, One Gateway Center, Pittsburgh 15222. Copyright ©1997-2003 PG Publishing Co., Inc. All Rights Reserved. http://www.post-gazette.com/pg/03333/245423.stm

