CHICAGO -- A sharp rise in stomach cancer among Navajo Indians during the past 20 years can be traced to uranium mining on their reservation in the Southwest, a researcher says.
The stomach cancer rate among the Navajos was once a tenth of the average, but is now three times greater than normal, with 12 cases per 100,000, said Dr. Richard Auld, with the Kaiser Health Group in Northern California.
Of 192 cases reported between 1965 and 1984, Auld found 82 percent occurred since 1975, about 12 years after uranium was discovered and began to be mined on the 25,000-square-mile Navajo reservation near the Four Corners in the Southwest, he said.
Auld, reporting Wednesday at a meeting of digestive disease specialists, said that time period corresponds roughly with how long it takes stomach cancer to develop. He said the cancers were also highly concentrated in areas where the uranium mines were, with some cancer rates 10 to 15 times the average.
Although the mines have been closed since the early 1970s, Auld said waste pilings from the mines still lay open on the reservation and that ground water and the food chain is still contaminated. The Navajos also sometimes use mud from the pilings to build their adobe huts, he said.
The problem probably is not confined to the Navajos, 'Other people living in the area have probably been exposed,' he said. 'It's only easier to see in the Navajos because they had such a low risk to begin with.'