Science Wednesday: Nitrogen, Think About It

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By Sarah Blau

Let’s just take a moment to think about nitrogen. Symbol: N. Atomic number: 7. Atomic mass: 14u. But unless you’re a chemist this doesn’t mean too much…

So let’s think about other aspects of nitrogen. Nitrogen is in the air we breathe, it is in the food we eat, it is a part of the necessary nutrients needed for life. Plants need nitrogen. Animals need nitrogen. We need nitrogen.

But, as is often the case, too much of a good thing is NOT a good thing. Nitrogen exists naturally in the environment, but human energy and food production have led to increased nitrogen levels in the air, land, and water. This excess of nitrogen in our natural resources contributes to many adverse impacts from decreased visibility in the air, to acid rain falling on land, to harmful algal blooms in water bodies, and more.

Nervous yet?

Luckily, EPA researchers take more than a moment of the day to think about nitrogen. They think about sources of nitrogen, the movement of nitrogen in the environment, the chemical changes of nitrogen, and the environmental and public health effects of nitrogen.

EPA scientists and partners in Iowa are testing newly created wetlands as treatment systems for lowering sediment and nitrogen pollution in surface waters draining into the Mississippi River.

In Narragansett, Rhode Island, EPA scientists are investigating how nitrogen from different sources interacts with other pollutants and affects lakes and reservoirs. Results will be used to develop computational tools for more informed nutrient management decisions.

Yet another EPA study focuses on the northern Gulf of Mexico, a.k.a. “The Dead Zone” where excess levels of nitrogen have had severe effects on the coastal ecosystem. Scientists are developing cutting-edge, 3D water flow and water quality models of the northern Gulf in order to inform decision-making about how potential nutrient management and climate change scenarios will affect the Gulf’s Dead Zone and the rivers and streams that feed into it.

EPA’s nitrogen research is ongoing at these and many other locations across the country to answer the overarching question: “How do we protect and sustain ecosystems and protect public health while also providing the material, food, and energy required by society?”

It’s a good question and a hard one to answer. So let’s be glad that EPA scientists know their chemistry.

About the author:  Sarah Blau is a student services contractor working with EPA’s Science Communication Team.

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