220
The Last Resource
example, has a half—life—the time taken to lose half its radio—
activity—of approximately eight days and need be stored for only a
Ï à}
few weeks or-months before its decay is completed, whereas the
Strontium—90 and caesium—137 produced from the re—processing of
nuclear fuels need to be kept out of circulation for 60010 900 years.
}
The greatest danger from the slight but continuous trickle of
radio—active material into the oceans lies in the way marine organisms
can hold radio—active elements in the life cycle. An illuminating
example of this occurred during a visit by U.S. scientists to the
Bikini Atoll, once the site of extensive nuclear tests. Navy oicers
,
were puzzled tond that levels of radio—activity onthe ships’ hulls
_
rose at night and decreased during daylight hours. The uctuations
,
were eventually traced to the dailymigrations of zooplankton which
had picked up and concentrated radio—active elements in their
bodies. More than ten years after the last nuclear test, land—dwelling
coconut crabs on the isla‘nds were-still accumulating such ahigh
concentration of Strontium—90 in their shells
…
that the meat was
unsafe to eat, and giantcla—ms living close to the-islands hadkidneys
so radio—active that they sent the surveycounters ‘o' the scale!
Of c0urse, the Bikini;At0 has been subject to an
radio-active
?For a realistic—example of pOllutionby radio—.
active materials in present timesone. mustlookatt power—stations,
1el—pr0œssing and military establishments. The-.stron‘tiurh—go and
caesium—137 released inthe efuents-from Windscale, Cumberland,
-
which
is such, thata— perŸs‘on-“eating‘a kilogram
of sh ‘caught over the
neàrest to .it— would ’not be
exposed to more than ”fo-7 ”per “cent of the perri‘Ssi-‘ole daily doses
set out bythe ICRP. Another, mu“ch—quotedeXamph of the.eare
taken over this question»bf radial—aCtiveapollution is “the Control ::ofthe
waste from the nuclear apower ;stati0n at Winfth in
limit is=said to be:govemedçhy a‘loC'al
proprietor ‘th
every day. Even if he continues to indulge
thro'ughouthis lifetime, his total dose of
'
to more
per cent ofthebackground;radiàtion.x
"
..:;—=:rA more
both thiclearand
cohvènti0nal ones, is the riskaof thermal
cooling
»;,:released
.
into coastal » and
Althoughthèîrwarm elùent
the
prodUCÇion:— by, fariihg _rapidlyængingï‘.'shÏPfand: “!ShCllä…,
sh;ir has also heeft known.
The Last Resource
example, has a half—life—the time taken to lose half its radio—
activity—of approximately eight days and need be stored for only a
Ï à}
few weeks or-months before its decay is completed, whereas the
Strontium—90 and caesium—137 produced from the re—processing of
nuclear fuels need to be kept out of circulation for 60010 900 years.
}
The greatest danger from the slight but continuous trickle of
radio—active material into the oceans lies in the way marine organisms
can hold radio—active elements in the life cycle. An illuminating
example of this occurred during a visit by U.S. scientists to the
Bikini Atoll, once the site of extensive nuclear tests. Navy oicers
,
were puzzled tond that levels of radio—activity onthe ships’ hulls
_
rose at night and decreased during daylight hours. The uctuations
,
were eventually traced to the dailymigrations of zooplankton which
had picked up and concentrated radio—active elements in their
bodies. More than ten years after the last nuclear test, land—dwelling
coconut crabs on the isla‘nds were-still accumulating such ahigh
concentration of Strontium—90 in their shells
…
that the meat was
unsafe to eat, and giantcla—ms living close to the-islands hadkidneys
so radio—active that they sent the surveycounters ‘o' the scale!
Of c0urse, the Bikini;At0 has been subject to an
radio-active
?For a realistic—example of pOllutionby radio—.
active materials in present timesone. mustlookatt power—stations,
1el—pr0œssing and military establishments. The-.stron‘tiurh—go and
caesium—137 released inthe efuents-from Windscale, Cumberland,
-
which
is such, thata— perŸs‘on-“eating‘a kilogram
of sh ‘caught over the
neàrest to .it— would ’not be
exposed to more than ”fo-7 ”per “cent of the perri‘Ssi-‘ole daily doses
set out bythe ICRP. Another, mu“ch—quotedeXamph of the.eare
taken over this question»bf radial—aCtiveapollution is “the Control ::ofthe
waste from the nuclear apower ;stati0n at Winfth in
limit is=said to be:govemedçhy a‘loC'al
proprietor ‘th
every day. Even if he continues to indulge
thro'ughouthis lifetime, his total dose of
'
to more
per cent ofthebackground;radiàtion.x
"
..:;—=:rA more
both thiclearand
cohvènti0nal ones, is the riskaof thermal
cooling
»;,:released
.
into coastal » and
Althoughthèîrwarm elùent
the
prodUCÇion:— by, fariihg _rapidlyængingï‘.'shÏPfand: “!ShCllä…,
sh;ir has also heeft known.