Answer:
1) Adverse effect on aquatic life also increase in biological oxygen demand.
2) Biomagnification of pollutants
Step-by-step explanation:
Water pollution is caused by unwanted addition of waste, animal debris, industrial effluents etc in a water body.
Water pollution may cause many direct and indirect harmful effects on environment. To name a few:
a) Decrease in level of oxygen leading to death of aquatic organism like fish.
Increase in biological oxygen demand.
b) Biomagnification: a pollutant may enter food chain from water and some pollutant may enter food chain contaminating other members of food chain.