Thousands Found Exposed to Hanford Plant Radiation

Radioactive iodine released from the sprawling nuclear weapons facility at Hanford, Wash., exposed as many as 13,500 residents of surrounding areas to heavy doses of radiation to their thyroids, scientists reported Thursday after a two-year review of once-secret government records.

Although the vast majority of the 270,000 people living in the vicinity received only low exposures during the peak of emissions between 1944 and 1947, infants and young children, drinking milk from cows grazing in the country immediately west of the complex, potentially could have been subjected to heavy exposure through the food chain.

The estimates made public at a news conference in Richland, Wash., said that 13,500 persons in the 10 surrounding counties could have received cumulative exposures up to 33 rads during the three years. Among some 1,400 infants and children drinking milk from cows grazing in Franklin County, just to the west of the complex, the median dose was put at 70 rads. A rad is a measure of radiation equal to what is absorbed in about a dozen chest X-rays.

Scientists involved in the study said that people could be put at risk at 9 rads and that they had chosen 33 rads as a point of concern to emphasize. Theoretically, the report said, a small number might have gotten a whopping 2,900 rads, but scientists said that the probability of such a high dose was low.

Nevertheless, said Sen. John Glenn (D-Ohio), chairman of the Senate Government Affairs Committee: “The study suggests that the Hanford residents may have been exposed to more radioactive iodine than from any industrial nuclear facility in the world.”

Over the course of three years, the body receives about one rad from natural background radiation and the government limits workers in nuclear facilities to an annual exposure of no more than five rads.

Scientists long have known that iodine emitted from the Hanford plant found its way into milk, increasing the risk of thyroid cancer. But the $15-million study under way is seeking for the first time to zero in on exposure levels and even identify the surviving individuals at greatest risk.

Nuclear engineer John Till, who chairs the project’s technical steering panel, said that the findings announced Thursday fully justify continuing the study, but he emphasized that the iodine danger in the area “is long since past.”

Iodine-131 is rendered harmless within months by the process of radioactive decay.

Hanford made the Tri-Cities area of western Washington an atomic boom town during the development of the United States’ first atomic bombs as 30,000 people moved into the remote area in the span of a year. Its reactors produced the plutonium fuel for the explosives, and the iodine was released from facilities reprocessing their spent fuel rods.

Energy Secretary James D. Watkins anticipated the release of the study at a press conference on Wednesday, stressing that the dangerous releases took place during a time when scientists and engineers had not yet comprehended the gravity of nuclear safety problems.

Although the radiation dose reconstruction project is being conducted independently, critics of the Department of Energy remain unhappy that the department is paying for it.

Legislation has been introduced in both the House and Senate to put the investigation in the hands of the Department of Health and Human Services.

Watkins’ assurances that the future of the Hanford facility will be devoted to environmental cleanup and management of its 600,000 cubic yards of radioactive waste rather than plutonium production have not mollified critics of the government’s record at the complex.

“The bottom line is that the department still wants to keep control of the information on health and safety,” said Rep. Ron Wyden (D-Ore) of the House Energy and Commerce Committee.

The extent of the iodine emissions first became public as a result of a lawsuit by environmentalists four years ago. Government documents released then showed that more than half a million curies of radiation had been emitted during a nine-year period in the late 1940s and early 1950s--thousands of times more than emissions during the Three Mile Island accident in Pennsylvania a decade ago.

Till told reporters that the exposure estimates, based on records inspection and mathematical models, are preliminary.

Next month, the panel plans a round of public hearings to answer questions and receive public comments in the Hanford area.

Over the coming three years, the project plans to refine the figures released Thursday while another study by the federal Centers for Disease Control in Atlanta seeks to estimate the number of thyroid cancers and other radiation-induced diseases.

Besides studying the airborne iodine hazard, the first phase of the dose reconstruction project reviewed the potential radiation exposures as a result of materials that Hanford released into the Columbia River between 1964 and 1966.

It concluded that about 70,000 persons eating fish from the river got doses of no more than 0.05 rad to their bones from radioactive phosphorous and about 1.7 rad to the gastrointestinal tract.