Rs from the Sky

How dangerous is radioactive fallout? At last week's Atlantic City meeting of the American Medical Association. Commander Robert A. Conrad of the Naval Medical Research Institute reported on the Marshall Islanders who were exposed to moderate fallout from the great test explosion in the Pacific on March 1. 1954. Talking to physicians, he did not prettify. The most intensive study was made of 64 Marshallese whose island got the heaviest fallout. Hours after the detonation. a snowlike material fell from the sky. It whitened their hair and clung to their skins. At first it had no ill effect, but during the night and the next day or two, about three-fourths of the people felt nausea. Their skins itched or burned, and tears ran from their eyes.

After two days the Navy took them all to Kwajalein Island and made vigorous efforts to decontaminate them. By this time their first symptoms were gone. Calculations showed that they had received about 175 roentgens of radiation, which is less than half of a deadly dose (400 R). But they were watched carefully.

A fortnight later, new symptoms began to show. The patients' dark skins grew darker in patches and rose up in leathery plaques. Sometimes the skin peeled away, leaving white or pink tissue. Deeper burns wept and formed crusts. When burns were on the scalp (70% of all individuals), the hair came out by the handful.

Tended by squads of Navy doctors, the burns healed eventually, leaving only scars or patches of discoloration. More long-lasting were the effects on the islanders' blood. The lymphocytes (one type of white blood cell) were reduced by more than 50%, and most of the effects lasted for six months at least. The children were hardest hit, but devoted care kept all of them alive.

The Navy concluded that most of the external damage came from the dust on the islanders' skins and in their hair. More clothing, better shelter and prompt decontamination would have reduced it. None of the Marshallese died. Fatal internal damage was prevented by removing them from their contaminated island--just in time. Probably 50 more roentgens would have killed at least some of them.

A distasteful job of Atomic Energy Commission officials is to tell Americans what to do if a similar bomb should contaminate a part of the U.S. Instructions prepared by AECommissioner Willard F. Libby contain little cheer.

A ten-megaton bomb (equivalent in energy to 10 million tons of TNT), says Libby, creates 1,100 Ibs. of radioactive fission products. Airborne for one day and then spread evenly over an area of 100,000 square miles, it would give each unsheltered person a dose of 67 roentgens per day. This is not far from the strength of the "snow" that fell on the Marshall Islanders.* They survived because they were evacuated promptly and cared for well, but as Libby remarks in an understatement, evacuation of 100,000 square miles (more than twice the size of New York State) "may be a bit impractical." Dr. Libby recommends that everybody stay indoors, preferably in a basement, where radioactivity will probably be low.

Then, when the level of radiation falls to about 6.7 R per day (after seven days), people may venture out cautiously. With radiation detectors (none are available in quantity) they must feel for pockets of extra-strong activity.

Finding the coast reasonably clear, people should get to work at the heavy labor of decontamination. Fire hoses will do a lot of good (if there is water), and shielded street-sweeping machines (not yet devised) will brush the contaminated asphalt. Heavy rain (if rain falls) will carry some of the deadly dust down the rivers to the sea. At last the interdict will be raised, and people can go about their ordinary business, avoiding dangerous areas and conscious that even in the safer places they are still receiving a considerable input of Rs.

To judge by the Navy's experience, many of the worst effects will not appear for weeks. The number of deaths, near-deaths and disfigurements will depend on how well the people have avoided radiation and have decontaminated themselves, and on how promptly they-have received good medical care.

*In practice, some places would get much more radioactivity, perhaps an amount quickly fatal in spite of precautions. Others would get less.

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