Question

Given figure represents biomagnification of $DDT$ in an aquatic food chain. Select the incorrect statement regarding this.

• A. When agricultural fields are sprayed with $DDT$, it is carried by runoff water into nearby aquatic bodies.
• B. River water may have a very low concentration of $DDT$, but the carnivorous fish in that river may contain high concentration of $DDT$, which is still suitable for consumption by human beings.
• C. Increased concentration of $DDT$ in birds affects calcium metabolism due to which egg shells become thin and break before maturity
• D. None of these

Answer 1

Answer: (B)

River water will always have a very low concentration of $DDT$, but as we go to higher trophic levels concentration of $DDT$ increases due to biomagnification. So carnivorous fish has high level of $DDT$ and it is not suitable for consumption by human beings, because of presence of $DDT$.