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effects of oil spilled in the oceans and
seas.
We don't often realize how much oil
is lost into the oceans every year. A loss
on the order of either the Torrey Can–
yon or the Santa Barbara, California,
oil spill represents
comiderably less
tha11 one percmt
of the yearly input of
oil into the sea from all sources.
These very spectacular local events are
but a small part of what is occurring
continuously on a worldwide basis
through smaller accidents, dumping,
waste, and spillage.
Most of these spills occur in conti–
nental shelf areas, the part of the ocean
teeming with abundant aquatic life.
There are also other intrusions into
the life-support systems of the oceans.
Hot water cffiuents from industry, waste
salt from desalinization plants, and
over-exploitation of fish resources are
a few examples. Then there is the most
notorious intruder into the aquatic web
of life - DDT.
Taylor A. Pryor is president of the
Oceanic Foundation at the Makapuu
Oceanic Center in Waimanalo, Hawaii.
In a sobering paper delivered at the San
Francisco UNESCO meeting, he re–
ported:
Ambouodor College l'hotos
Mountains of Garbage
-
left, waste
dumped at landfill; above, huge mounds
of waste, junk and garbage al a los
Angeles dump; right, millions of junked
cars yearly produce mountains of ugliness
over the landscape.
"One investigator cannot find an un–
contaminated sample of surface sea
water within three hundred miles of the
California coast. Tetraethyl lead, carried
in the atmosphere from auto exhaust,
reaches that far.
"Farther yet is the reach of DDT. An·
tarctic penguins carry an increasing load
of this 'hydrocarbon and can eventually
be considered
candidates for extinction
along with the brown pelican.
"Since marine organisms seem to con–
centrate DDT in large amounts as they
move up the food chain, the predators
on top of the chain are trapped. Already
the Atlantic bottlenose porpoise off the
Florida coast carries 800 ppm of DDT
in blubber while the Department of Ag–
riculture permits 5 to 10 ppm in sa–
lable meat. But for once the great
whales may have a break with their re–
servoirs of fat for ready absorption.
"Not so for the sea birds.
lt is hard
to say yet, but they may
al/
be doomed
now.
Most of the DDT ever used is still
active in the atmosphere or locked in
soils ready to be removed by evapora–
tion or by run-off into the sea. With a
10- to 50-year half-life remaining, what
effects will follow? How much seafood
will human predators be able to con·
sume?"
Yes, even if all DDT usage were ban–
ned now, scientists are predicting - in
fact expecting - that it's already
too
late to avoid wholesale extinction of
many life forms in the ocean com–
munity.
The publicity given to the pollution
problems caused by DDT compounds
has tended to minimize the threat of
other environmental pollutants. But the
pesticide problem is only half the story.
The most abundant synthetic pollu–
tants in the marine environment, after
the DDT compounds, may be a dass
of chemicals called polychlorinated
biphenyls, oc PCB. They are used in such
vast amounts in industry that they can
be purchased in railway cae quantities.
Sorne of the principal uses are as plas–
ticizers and fue retardants. They are
found in many plastics, rubbers, paints,
hydraulic fluids, and in countless other
industrial products.
The problem is, these powerful
chemicals are now found worldwide
in
fish and marine birds- as is DDT.
The PCB compounds are extremely
stable. They do not dissolve in water.
They readily enter biological systems