Which statement is true about groundwater or surface water contaminated by pesticides?

Which statement is true about groundwater or surface water contaminated by pesticides?

• A. Runoff and erosion are sources of surface water contamination by pesticides.
• B. Groundwater contamination occurs only from spills.
• C. Pesticides cannot contaminate surface water.
• D. Rainwater cleanses water instantly.

Answer: (A)

Think about how chemicals move from land into water. For surface water, rainfall or irrigation water running over fields can pick up pesticide residues and carry them into streams, rivers, and ponds. Erosion also contributes, as soil particles bound with pesticides are washed into water bodies. These pathways are classic sources of surface water contamination by pesticides. Groundwater gets contaminated mainly through leaching and percolation of pesticides down through the soil into aquifers; spills are not the only way this happens. Pesticides can indeed contaminate surface water, so the statement claiming they cannot is incorrect. Rainwater does not instantly cleanse water; it can move pesticides into water bodies and may dilute them, but it doesn’t instantaneously purify.

Think about how chemicals move from land into water. For surface water, rainfall or irrigation water running over fields can pick up pesticide residues and carry them into streams, rivers, and ponds. Erosion also contributes, as soil particles bound with pesticides are washed into water bodies. These pathways are classic sources of surface water contamination by pesticides.

Groundwater gets contaminated mainly through leaching and percolation of pesticides down through the soil into aquifers; spills are not the only way this happens. Pesticides can indeed contaminate surface water, so the statement claiming they cannot is incorrect. Rainwater does not instantly cleanse water; it can move pesticides into water bodies and may dilute them, but it doesn’t instantaneously purify.