DDT content in the water of a lake that supplies drinking water to the nearby
villages, is found to be 0.003 ppm. The kingfishers of that area were reported
to have 2 ppm of DDT. Why has the concentration increased in these birds?
What harm will this cause to the bird population? Name the phenomenon.
1. DDT is a non-biodegradable pollutant. It can not be utilized and excreted out from the
body of living organisms, hence gets accumulated at different trophic
2. From water, it accumulates in phytoplanktons then to fish and finally to predatory birds.
3. Higher concentration of DDT diturbs calcium metabolism in birds
resulting in thinning of egg shells, and their premature breaking.
This phenomenon is called biomagnification.