1. Water - Primary consumer
Oil - Biomagnification compounds like DDT, mercury

2. The concentration of oil increased from one trophic level to other trophic level.

3. The oil is accumulated if we goes from one trophic level to other level leads to accumulation of oil
so it refer as biomagnification.

4. because the compound intake by organism not able to digest so it accumulate inside the body if we goes from one trophic level to higher trophic level and cause a serious side effects to the higher trophic level organism even death.