The Tale of the Hanford Sheep

Part One

The great Herb Parker used to tell the following story—a story that provides the little known background to a series of classic studies performed by Leo Bustad at Hanford.

In the late 1940s, environmental surveys around Hanford revealed elevated I-131 concentrations in the thyroids of the local fauna. This finding indicated that reactor operations at Hanford, and elsewhere, might result in the deposition of substantial radioiodine on pasture land—radioiodine that could be ingested by grazing animals. To determine the effects of this intake on sheep, and to identify any possible effects in their offspring, Leo Bustad and his coworkers initiated a series of experiments. These studies, which continued throughout the 1950's, are probably the first multigenerational investigations into the effects of radionuclides on large animals (Stannard 1988).

The first thing that the investigators had to accomplish was the establishment of a successful breeding program. No effort or expense was spared e.g., the experimental facilities were set up in a remote area (near one of the reactors) in order that the sheep not be disturbed. The pens were even constructed of stainless steel to facilitate decontamination!

But things didn’t go as planned! The sheep weren’t becoming pregnant! Something had to be done, so an observer was sent out to the pens to see what was, or wasn’t, going on. He returned with the following report: the rams were eager to complete their assignments, but every time they got to work, their hooves would slip and slide all over the steel floor. No traction! It wasn’t just the investigators who were frustrated.

After ruminating over the matter, the investigators came up with a perfect solution: condoms—put them over the rams’ feet! Well that did the trick, and it probably represents the only time that condoms have been donned to ensure pregnancy!

Part Two

One of the hallmarks of this column is the unrelenting demand for accuracy. Even a story of Herb Parker’s has to be checked out. It wasn’t easy, but I managed to locate the man with the most intimate knowledge of the whole affair—Leo Bustad.

Leo said that he was sorry to report that Parker’s story was largely, although not entirely, a fabrication. It was true that the sheep weren’t becoming pregnant because the rams were unable to get traction. But, the floor of the pens wasn’t stainless steel, it was concrete covered with a frequently wet rubber pad. Furthermore, the answer lay not in condoms, but in spreading sawdust over the floor to absorb the moisture.

That, and replacing the old rams who had grown timid, with younger ones who, according to Leo, "had the reckless abandon of a second lieutenant!"

Unless noted otherwise, the information in this "Tale" was obtained in personal communications with Merril Eisenbud and Leo Bustad.


  • Bustad, L.K., ed.. Proceedings of the Hanford Symposium on the Biology of Radioiodine. Health Physics 9(12):1081-1426; 1963.
  • Stannard, J. N. Radioactivity and Health—A History. Battelle Memorial Institute; 1988.