Health Risks of Ionizing Radiation: - Clark University

148 Communities Near Nuclear Facilities
Figure 12-2. A leaky drum at the 903 pad at Rocky Flats.
Photo courtesy of the U.S. Department of Energy http://
www.rfets.gov/doe/HAER/RockyFlats_HistoryBook_
rev2.pdf
processing plants in Pennsylvania (Boice et al.
2003a, 2003b). The Apollo and Parks facilities were
less than three miles apart and could be treated as one
source of exposure. Although the local rates of colon
cancer and cervical cancer were significantly higher
than Pennsylvania rates, the cancers associated
with likely exposures from the plants were not
significantly increased and the total cancer incidence
was not increased (SIR 1.01, 0.93-1.10). There were
18 leukemia cases, compared to 12.4 expected, for a
SIR of 1.45 (0.86-2.30). Cancer mortality rates were
not different from the rates for control counties in
Pennsylvania but there did appear to be an increase
in mortality from multiple myeloma, leukemia and
all cancers after the plants started up 5 .
Communities exposed to contamination from
uranium mining and milling may experience health
risks. Au et al. (1998) measured chromosome
aberrations in residents next to mining and
milling sites of Karnes, Texas. The study found a
nonsignificant increase in chromosome aberrations,
and significantly compromised DNA repair
responses, compared to controls. Another study
focused on birth outcomes in Navajo families near
the Shiprock uranium mining area (Shields et al.
1992). These authors found an increased risk of
congenital birth defects in mothers living near
tailings or mine dumps (OR 1.83, 1.0-3.5) or mines
(OR 1.43, 0.72-2.56) 6 .
Multi-site studies in the US. A National Cancer
Institute study looked at cancer mortality rates in
107 counties adjacent to 61 nuclear facilities (mainly
commercial power facilities) and did not detect any
mortality excess (Jablon et al. 1991). This study
did, however, find significantly increased childhood
leukemia incidence in four Connecticut and Iowa
counties. Mangano et al. (2002) studied areas
downwind of eight nuclear plants before and after
the plants closed. They found that infant mortality
and childhood cancer incidence declined after plant
closure and that the declines were significantly
greater than average declines nationwide. This was
followed by an assessment of childhood cancer
incidence in counties adjacent to 14 east coast
nuclear power plants (Mangano et al. 2003). At all
sites there was an apparent excess and the overall
excess of ~12% was highly significant. This study
also determined that Pennsylvania counties within
30 miles of a nuclear power facility (about half
of the state) had a childhood leukemia rate 10.8%
higher than the national average 7 .
12.3 UK studies
There have been many studies of cancer clusters
in the UK, particularly childhood leukemia clusters,
and some of these occur near nuclear facilities. One
controversial explanation of these clusters involves
fathers who work at the facilities. It has been
proposed that radiation exposure before conception
might damage sperm cells and pass a cancer risk on
to the child. Although this possibility is relevant to
communities living near the facilities, we deal with it
separately in our preconceptional irradiation section
and in an appendix. The studies that we discuss
below involve exposures received by communities
5 During 1950-64, 1965-79 and 1980-95 the relative risks for multiple myeloma were 0.91, 0.92 and 1.04. Corresponding
estimates for leukemia were 0.89, 0.86 and 0.97, and for solid cancer 0.96, 0.95 and 0.98. The two facilities began
operations in 1957 and 1960.
6 Shields et al. (1992) also found evidence that occupational or residential exposure of fathers could be a risk factor.
This is discussed further in the section on preconceptional exposures.
7 Childhood leukemia in the rest of the state was 11.5% below the national average (Mangano et al. 2003).