What is a common environmental concern with improper pesticide application?

Water contamination is a significant environmental concern associated with improper pesticide application. When pesticides are applied incorrectly, such as in excessive amounts or during inappropriate weather conditions, they can be washed away by rain or irrigation runoff. This runoff can carry harmful chemicals into local water sources, affecting both surface water and groundwater. Consequently, non-target organisms, including aquatic life, can be harmed, and the quality of drinking water can be compromised, posing risks to human health and ecosystems.

While other options like soil erosion, pest resurgence, and increased crop yield relate to agricultural practices, they do not directly address the issue of environmental contamination in the same way. Soil erosion can occur due to various factors, not limited to pesticide use, pest resurgence refers to the return of pests as a potential outcome of mismanagement, and increased crop yield generally signifies beneficial outcomes of proper agricultural practices rather than being a concern. Thus, the focus on water contamination highlights a crucial aspect of responsible pesticide use and its broader implications for environmental health.