Study the picture given below (industrial effluent and oil being discharged into a water body, with dead fish visible) and answer the following questions: Study the picture given below (industrial effluent and oil being discharged into a water body, with dead fish visible) and answer the following questions:
Name one pollutant that causes the above pollution.
Topic: Water pollutants
Answer
INDUSTRIAL EFFLUENTS (also acceptable: sewage, oil spills, chemical fertilisers and pesticides washed from fields).
One pollutant only, so name one.
Adding its EFFECT strengthens the answer: industrial effluents carry heavy metals such as MERCURY and LEAD, which accumulate along the food chain — mercury causing MINAMATA disease and lead damaging the nervous system.
Two other sources worth knowing: SEWAGE — carries pathogens and, as it decomposes, consumes the dissolved oxygen so that fish suffocate FERTILISER RUN-OFF — causes EUTROPHICATION, an explosion of algal growth that blocks light and strips the water of oxygen when the algae die