That's actually not correct. The studies they quoted are from the IOM studies. There are a number of studies, more than that, and in fact the president commissioned a comprehensive review to include the IOM studies and the studies that did not make it into the IOM.
If you look at the back of this, you'll see a list of different facilities that were tested. There are a number of facilities that were discovered that were not included and with the presidential order had to be included, and they all showed significantly higher levels of cancer incidence. When those came out, that is when the U.S. changed their policy and started a warning for their workers.