A histological kidney study of uranium and non-uranium workers.

Kidney tissue sections were obtained at autopsy from seven persons with a history of low level occupational exposure to uranium and histologically compared in a blind study with similar sections obtained from six reference cases. The pathologist was unable to identify the uranium workers or any uranium-specific nephropathy. This suggests that the chronic low level of kidney uranium concentration experienced by these workers, which was an order of magnitude lower than the accepted permissible level of 3 microgram per gram, did not induce any identifiable permanent tissue damage.