Question

how do you think throwing waste into lakes and rivers would affect the water creatures living there?​

Answer 1

Answer:

Water used for cooling is warmer than the river itself, and this is also a form of pollution.

People are sometimes careless and throw rubbish such as bottles and crisp packets directly into rivers. Polluted water also carries diseases. 

When animals drink the water,  they may get diseases which can kill them.

Answer 2

Biomagnification

Eutrophication-Toxicity in marine food chain increases

Algal Bloom-Algae form in the water bodies and use up oxygen of water killing marine organisms.

Mainly death of marine organisms

Radioactive pollutants cause mutation in fishes(Refer Minamata Tragedy)