Fermi, Feynman, others. A NMHD study more or less confirms it (although some types of cancer were actually lower):
"1. Los Alamos County experienced a modest elevation in brain and nervous system cancer incidence during the mid- to late-1980s. Incidence in the county during this time period was 70%- 80% greater than that observed in a New Mexico state and a national reference population. Due to the small number of cases, random fluctuation in the LAC incidence could not be ruled out as causing the observed elevated incidence.
...
6. Los Alamos County experienced a sudden and marked increase in thyroid cancer incidence in the mid-1980s. The 1986-1990 county thyroid cancer incidence rate was nearly four-fold higher than the rate for a New Mexico state reference population. For the preceding time period 1981-1985, thyroid cancer incidence in the county was roughly similar to the state incidence. The recent increase in the county thyroid cancer incidence was found to be unrelated to recent advances in high-frequency thyroid ultrasonography.
7. Breast cancer incidence in Los Alamos County women was elevated during the entire 21-year time period 1970-1990. County breast cancer incidence rates consistently were 10%-65% higher than state and national reference rates. Reproductive and demographic factors known to increase the risk of breast cancer, including urban residence, high socioeconomic status, and delayed age at first full-term pregnancy, have been prevalent in the county over the past two decades.
8. Ovarian cancer incidence in Los Alamos County women was elevated between the mid- 1970s and 1990. For the latest five-year time period 1986-1990, ovarian cancer incidence in the county was roughly two-fold higher than that observed in a New Mexico state reference population. The majority of the excess ovarian cancer incidence was confined to the census tract corresponding to the North Mesa and Barranca Mesa neighborhoods. Incidence in this census tract was four to six- fold higher than that observed in the remaining census tracts.
9. The incidence of melanoma in Los Alamos County was elevated over the entire 21-year time period 1970-1990. Peak elevations in the county incidence rates occurred during the mid- to late- 1980s. Melanoma incidence in the county during this time period was approximately two-fold greater than that observed in a New Mexico state reference population. The excess melanoma incidence observed in Los Alamos County may in part be related to the high ambient solar UV radiation intensity thought to exist in the county due to its high altitude.
10. The incidence of leukemia was comparable to or lower than that observed in a New Mexico state and national reference population. The incidence of other cancers of the lymphoreticular system (excluding non-Hodgkin's lymphoma) also was comparable to or lower than that observed in the reference populations. The incidence of non- Hodgkin's lymphoma consistently was elevated in Los Alamos County during 1970-1990. County incidence rates typically were 20%-60% greater than those observed in a New Mexico state and a national reference population."
http://www.google.com/url?sa=t&source=web&cd=4&ved=0CC8QFjAD&url=http%3A%2F%2Fwww.doeal.gov%2FSWEIS%2FOtherDocuments%2F313%2520athas1993.pdf&rct=j&q=cancer%20los%20alamos%20new%20mexico%20health%20department%20study&ei=2mMHTsu-IqPhiAKdnP3DDQ&usg=AFQjCNGPVWLxPtQKyrtoaV5ShJqfRo9Krg&cad=rjaI don't argue a link between exposure to radiation and cancer, but the conclusion that the rubble "is" radioactive because it's "potentially" radioactive.