Question

Biomagnification of DDT in a aquatic food chain starting from water having a concentration of 0.003 ppb may go, in fish eating birds, upto

• A. 2 ppm
• B. 25 ppm
• C. 50 ppm
• D. 100 ppm

Answer 1

The correct option is B 25 ppm

Persistent pesticides like organochlorine or chlorinated hydrocarbons like DDT pass into food chains and increase in amount per unit weight of organisms with the rise in trophic levels due to their accumulation in fat. The phenomenon is called biomagnification or bioconcentration. e.g., 0.003 parts per billion in water, 2.5 parts per billion in phytoplanktons, 40 parts per billion in zooplankton, 0.5 parts per million in clams and small fish, 2 parts per million in predator fish and 25 parts per million in fish-eating birds like Sea Gulls.

So, the correct answer is '25 ppm'