Since 1915, chemical fertilizer has been mass produced for farming. Which of the following is the main water pollution problem caused by chemical fertilizer?

increased carbon monoxide

radioactive substances in the water

increased nitrate and phosphate levels

higher levels of bacteria, viruses, and protozoa

Chemical fertilizer increases nitrate and phosphate levels

Answer : The correct answer is 3) Increased nitrates and phosphates level.

Chemical fertilizer:

These are substances that are applied into soil or directly to plants to provide them optimal nutrition for their growth and development. These are also known as synthetic fertilizers.

These chemical fertilizers contain Nitrogen as nitrates, phosphorous as phosphates and potassium as salt of it.

Example : Urea. ammonium nitrate etc.

When these chemical fertilizers are sprinkled over plants or given to soil, during rain, they enter water bodies through runoff and contaminate them.

Due to which the nitrates and phosphates enters water bodies and cause Eutrophication. Eutrophication causes excessive growth of algae which in turn causes oxygen deficient in water bodies.

This is how fertilizer pollute the water bodies by increasing the level of nitrates and phosphates.

Hence option 3) Increases nitrates and phosphates level is correct answer.