What environmental hazard is associated with pesticide use?

Water contamination through runoff or leaching is a significant environmental hazard associated with pesticide use. When pesticides are applied to agricultural fields or lawns, there is a potential for these chemicals to be washed away by rain or irrigation, leading to runoff into nearby water bodies. Additionally, pesticides can leach through the soil, reaching groundwater sources. This contamination can pose serious risks to aquatic ecosystems, drinking water supplies, and overall water quality, affecting not just wildlife but also human health.

On the other hand, the other choices do not accurately reflect the impacts of pesticide use. Air quality improvement is not a direct result of pesticide application, as pesticide use can often contribute to air pollution through volatilization. Soil enrichment is also misleading, since while certain agricultural practices can enhance soil quality, the application of pesticides often disrupts soil microbial communities and can lead to long-term soil health issues. Increased biodiversity is typically not a direct benefit of pesticide use; instead, pesticides can harm non-target species, leading to a decrease in biodiversity as sensitive organisms are affected by the chemicals.