Question

explain biological magnification

Answer 1

Biological magnification is the process of accumulation of certain harmful chemicals at each trophic level in the food chain leading to a higher concentration at each trophic level.
As humans are at the top of almost all food chains they are the most affected.
For eg: If chemical concentration in planktons is 0.5ppm the fishes which eat it have a concentration of nearly 5 times more.
As the food chain goes on in the end the top carnivore like humans have a concentration of nearly 1000ppm.
This is how Biological magnification works.

Answer 2

Biological magnification is the accumulation of or increase in the amount of pollutants and chemicals in each tropic level.
It increases after each tropic level.
This is the main reason why the vegeteranians are much fitter than the non vegeteranians.