Why are nitrogen and phosphorus specifically regulated?

Nitrogen and phosphorus are specifically regulated because they can cause significant environmental harm if not managed properly. When these nutrients are applied excessively to agricultural lands or urban areas, they can run off into water bodies, leading to nutrient pollution. This process can contribute to problems such as algal blooms, which deplete oxygen in water and harm aquatic life, disrupting ecosystems. Additionally, the overabundance of nitrogen and phosphorus in water can lead to issues like eutrophication, which negatively affects water quality and can result in dead zones where marine life cannot survive. Therefore, regulations are in place to ensure that their application and use are controlled to reduce the risk of these environmental impacts.