How from PCBs fish die?

Question

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Answer 1

Different pollutants work differently. Some, such as PCBs, are subtle. A female striped bass produces 6 million eggs in a lifetime. If some die from PCBs, it won't be noticed. But humans are also affected when they eat fish contaminated by PCBs; the chemicals can cause cancer and disrupt the functioning of hormones in the body. Other forms of pollution, like nitrate and phosphate runoff from farms, kill the ecosystem by starving fish. These nutrient pollutants are found in fertilizer and in sewage, and they cause excessive growth of aquatic plants when they hit the water. Algae, during their natural course of life, die and sink to the bottom, where they are devoured by bacteria, which use oxygen. Too many algae deprive fish of oxygen.

Yet as he indicated earlier, Kennedy does not see factories as blights on Eden but as signs of a rich and useful economy. Neither he nor Cronin is opposed to industry, condominium construction, powerboat use or anything that might bring the fullness of communal American life into contact with the river. They simply oppose anyone destroying the river. "This is a fight to save a resource for as many constituencies as possible," says Kennedy. "Here there is room for everyone." As he speaks, a trio of ducks puts on a brief air show high above the electrical wires that cross the river. A great blue heron is spotted over the Lovett plant.-