What is the main concern with pesticide leaching?

The main concern with pesticide leaching is the contamination of groundwater. Leaching occurs when pesticides dissolve in water and move down through the soil layers, potentially reaching groundwater sources. This can pose significant risks to drinking water supplies, environmental health, and public safety. Groundwater is often a crucial source of water for various uses, including agricultural irrigation and human consumption. If contaminated, it can lead to health problems for individuals who consume this water, as well as affect ecosystems relying on these water sources.

While other options discuss important environmental issues related to pesticides, such as air pollution and surface water contamination, leaching specifically addresses the movement of pesticides through the soil and their potential to infiltrate groundwater supplies, which is a significant concern for long-term environmental health and safety.