It is found that the bioaccumulation was lesser in monsoon season than pre and post monsoon seasons.

The heavy metals could find their way into human beings through food chain. This bioaccumulation cause various physiological disorders such as hypertension, sporadic fever, renal damage, nausea, etc.

It is concluded that unplanned urban settlements, combined with the proliferation of unorganized small-scale industries and the sewage lead to the contamination of the EBWR. Such increased bioaccumulation of heavy metals in fishes not only disturbs aquatic life but also increases health risk in human beings through food chain.

Where do the pollutants enter the water sources from?
How do heavy metals enter the fishes living in this water?
Researchers found that pollution levels increase during monsoon season. Why they found so?
Why did people living in the areas near by the water reservoir, suffer from various diseases?

In many areas man has changed the natural ecosystems to a great extent by damming rivers, draining marshes, re-claiming land from the sea, cutting down forests, plough-ing up land and growing crops, and by building towns, cities, canals and motorways. These changes have greatly altered the communities of plants and animals living there.

Consider the development of a large town, for example. There will be three kinds of change.

a) Some plants and animal species will die out.
b) Some will adapt to the new conditions sufficiently to survive in reduced numbers.
c) Some will benefit by the new conditions and will increase in numbers.

Do you know?

Minamata disease was first discovered in Minamata city in Kumamoto prefecture, Japan, in 1956. It was caused by the release of methyl mercury in the industrial wastewater from the Chisso corporation’s chemical factory, which continued from 1932 to 1968. This highly toxic chemical bioaccumulated in shellfish and fish in Minimata Bay and the Shiranui Sea, which, when eaten by the local population, resulted in mercury poisoning. While cat, dog, pig and humans deaths continued for 36 years.

Let us read the following story to know how cruel the human actvities are against the nature.



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