"Within the first three days after the detonation, the resident populations of Rongelap (including some present on Ailinginae) and Utrik, as well as American weather servicemen on Rongerik, were evacuated to avert continued exposure and to provide immediate medical care."

Some of those exposed had skin burns due to fallout.

Radioactive Iodine-131 was measured in the urine of adults from Rongelap and Ailinginae about two weeks later. That data was valuable to present researchers seeking to calculate dosage to the groups.

"In contrast, similar data do not exist for populations who were living on other atolls of the Marshall Islands and radiation doses to Marshallese living there have, consequently, been difficult to assess."

The federal government has provided medical care and documented health effects among what the report calls "the highly exposed Marshallese." But only two epidemiologic studies have been carried out, one of benign thyroid disease and thyroid cancer.

"To date, there has not been an epidemiologic study of the Marshallese to estimate the total numbers of cancers and other serious illnesses resulting from exposure to radioactive fallout." But it was possible to estimate how many cancers would develop among the population, including those caused by fallout.

Among the ways people were exposed were externally, through fallout on the ground or air outside of the body; and internally, through such routes as inhalation, drinking fallout-laced water, using eating utensils with fallout on them, or consuming food contaminated by fallout.

Because radioactive material went into the soil, contaminated food may have been eaten "months and years after the deposition of fallout." Some amount of radioactive Cesium is still present in the soil of certain islands.

"Estimated doses at Rongelap and Ailinginae, as expected, were very high, particularly to children — in the range of tens to more than one hundred Gray (a measurement of radiation) depending on the age at exposure and the particular organ" of the body.

"Doses of that magnitude from accident situations have rarely, if ever, been documented."

Estimates of the amount of fallout varied according to where the person lived. "For example, at the more distant locations, e.g., Kwajalein, Majuro, etc., ingestion of fallout would probably play a much less important role than we assumed and inhalation of fallout would be more important."