Which property of a pesticide would make it more likely to move with water in surface runoff?

• A. High solubility
• B. High volatility
• C. Low molecular weight
• D. Low water solubility

Answer: (A)

Movement with surface runoff hinges on how well the pesticide dissolves in water. If a pesticide is highly soluble, it stays dissolved as water from rainfall or irrigation flows across the field, so the pesticide can ride along with that water and be carried away with runoff. In contrast, pesticides with low water solubility tend to stick to soil particles and stay put rather than moving with the water, and those that are highly volatile may evaporate before runoff forms. So the property that makes runoff movement more likely is high solubility in water.