Registered Environmental Health Specialist (REHS) Practice Exam

Nitrate contamination in water is most commonly associated with farming practices. This is primarily due to the use of fertilizers that contain nitrogen, which, when applied to crops, can leach into the groundwater and surface waters as the nitrogen compounds break down. When rainfall occurs, these nitrates can be washed away from agricultural fields and into nearby streams, rivers, and aquifers, leading to elevated nitrate levels in drinking water sources.

Farming practices often involve high-intensity agriculture that utilizes synthetic fertilizers, which are particularly rich in nitrates. Additionally, animal waste from concentrated animal feeding operations can also contribute significant amounts of nitrates to the surrounding environment as it is often used as a fertilizer without proper management practices to minimize runoff. This agricultural influence on water quality through nitrate leaching is well-documented and recognized by environmental health specialists as a major source of contamination.

In contrast, while industrial waste, urban runoff, and residential landscaping can have impacts on water quality, their contributions to nitrate levels are typically much less significant than those stemming from agricultural activities.