- 69 The radioisotopes in the ocean are those that
occur from natural sources,
posal of radioactive waste.
from fallout,
or from dis-
The radioactivity in sea
water from naturally occurring radioisotopes is about
750 disintegrations per minute per liter,
of which «40
contributes ninety-seven per cent of the activity.
The
greatest amount of radioactivity added to the ocean has
been in the area of local fallout near Bikini-Eniwetok
Atolls.
The amount of radioactivity from fallout in a
liter of sea water, immediately following a detonation
may be thousands
of times greater than the amount from
x40; within one year, however, the amount is less than
from KO,
From the Bikini-Eniwetok area, fallout is
carried westward by the North Equatorial Current system
at a rate of seven to ten miles per day.
Radioactive wastes may be the principal source
of radioisotopes in the ocean in the near future but at
the present time the contribution from this source has
been negligible.
Biological effects from radioisotopes in the ocean
should be especially evident in the Bikini-kniwetok area;
however, gross population changes or morphological abnormalities have not been observed in samples from the area,