What environmental issue does pesticide runoff cause?

Pesticide runoff is a significant environmental concern primarily because it can contaminate water bodies. When pesticides are applied to crops or land and heavy rainfall occurs, the chemicals can be washed away into nearby streams, rivers, lakes, and other water sources. This contamination can lead to adverse effects on aquatic ecosystems, harming fish, amphibians, and other wildlife that depend on these habitats. Not only does it affect biodiversity, but it can also pose a risk to human health as these chemicals can enter drinking water supplies. Thus, the understanding of pesticide runoff highlights the need for responsible pesticide application and management practices to protect water quality and aquatic life.