Word: plankton
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Dates: during 1960-1969
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...gallons of spilled oil every year-about ten times the amount that oozed from the Torrey Canyon, and enough to coat a beach 20 ft. wide with a half-inch layer of oil for 8,633 miles. Scientists are increasingly worried that this oil could be poisonous to ocean plankton, a key source of photosynthesis that produces most of the earth's oxygen...
...causing cancer in mice, and of upsetting whole ecosystems. It is ubiquitous, appearing unexpectedly in Lake Michigan's coho salmon and even in Antarctica's snows, where it is carried by winds. Some scientists fear that DDT, washed into oceans, may kill off the plankton that supplies 70% of the earth's oxygen...
Sound's tiny Zooplankton (.04 ppm), then built up further in the fatty tissue of plankton-eating fish (.5 ppm). These small fish, in turn, were devoured by larger fish with yet another increase in DDT concentration (2.0 ppm). By the time the chemical had passed into the bodies of such fish-eating birds as cormorants, mergansers and ospreys its concentration (25 ppm) had increased an astounding 10 million times over the original amount (see diagram...
Airborne Cats. Beyond the danger to fish and birds lies DDT's threat to the whole ecological system. Concentrations of DDT no larger than a few parts per billion in plankton, says Biologist Charles F. Wurster Jr., chief scientific adviser to a New York conservationist group called the Environmental Defense Fund, can substantially hinder the photosynthesis process. On a larger scale, such interference could have a devastating effect, since phytoplankton produces 70% of the earth's oxygen...
...from U.S. lakes daily by commercial and sport fishermen is contaminated. A classic example is Clear Lake, Calif., where DDT (at the minuscule proportion of two one-hundredths of a part per million parts of water) was used to kill off a troublesome, lake-hatching insect. As a result, plankton accumulated DDT residues at five parts per million; fatty tissue of fish feeding on lake-bottom life was found to contain several hundred to 2,000 parts of DDT per million; grebes and other diving birds died from eating the fish. The New York health department reports high concentrations...