the concentration expected from Fig.
l.
through the data points.
From this
Thus, there is little question that
curve, the concentration of plutonium
the plutonium levels in the air of
expected in air at the latitude of
Bikini Island around the first part
Bikini during May 1972 is approxi-
of June 1970 were above fallout-
mately 16 aCi/m>.
plutonium background levels for that
normal median (21 aCi/m>) of actual
latitude.
concentrations at Bikini is only
The only mechanisms that
While the log
could cause such levels are resus-
slightly more than this value, the
pension processes on the island.
mean plutonium air concentration
The median concentration at Bikini
detected at Bikini during this period
was very nearly equivalent to the
(34 aCi/m>) was twice this expected .
mean air concentration at New York
value.
during this period in 1970.
were detected in the air at New York.
Remember
In this same month, 37 aci/m>
that during 1970 the urine concentra-
Again we find a similarity between
tions from Bikini and New York were
the levels of plutonium in Bikini and
also comparable.
New York air, and the Bikini mean
Except for water
and possibly some fish, no indigenous
concentration is again higher than
material was consumed at Bikini
expected for this latitude from
during 1968 and 1969.
worldwide fallout concentrations,
From this
comparison of New York and Bikini,
The 1972 data on air concentration
the 1970 data strongly suggest a
of plutonium at Bikini also showed a
close correlation between plutonium
strong geographic correlation.
levels in air and concentrations in
plutonium air concentrations in the
urine.
samplers increased from northwest to
In May, 1972, air samplers were
The
southeast along the length of the
again operated on Bikini Island at
island.
four different locations.
the island have higher plutonium air
239,240
The
.
.
Pu air concentration during
this period ranged from less than 6
to 80 aCi/m>.’
The log normal median
Therefore, some regions of
concentrations
than others.
The
. individual's inhalation exposure,
then, must also depend on the time
concentration over the island was
spent in specific regions of the
21 aCi/mn, and the mean concentration
island.
was 34 aCi/m>
In Fig. 2 the HASL
In summary, the data on air con-
air concentrations of plutonium
centrations of plutonium at Bikini
during May 1972 are plotted as a
are rather sketchy, and we do not
function of latitude.® A smooth
know how different the concentrations
continuous curve has again been drawn
in large volumes of open air are from
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