Which of the following are correctly matched ?
1. Arsenic poisoning - Black-foot disease
2. Secondary effluent treatment - Biological process
3. Pyrolysis - Waste disposal
4. Tubifex - Water pollution indicator
5. Biomagnification - Degradable pollutants
The correct option is E 1, 2, 3 and 4
Biomagnification refers to increase in concentration of the toxicant at successive trophic levels. This happens because a toxic substance accumulated by an organism cannot be metabolised or excreted, and is thus passed on to the next higher trophic level. This phenomenon is well known for mercury and DDT.