Question

Explain how pollution by sewage causes dissolved oxygen levels to decrease

Answer 1

When toxic substances enter a body of water, they will be dissolved, become suspended in water or get deposited on the bed of the water body. The resulting water pollution causes the quality of the water to deteriorate and affects aquatic ecosystems. Pollutants can also seep down and effect groundwater deposits. sewage and industrial wastes are discharged into the rivers. Because of this, pollutants enter groundwater, rivers, and other water bodies. Such water, which ultimately ends up in our households, is often highly contaminated and can carry disease-causing microbes.