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Science Wednesday: Nitrogen, Think About It

2012 January 11

Each week we write about the science behind environmental protection.Previous Science Wednesdays.

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.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

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9 Responses leave one →
  1. Arman permalink
    January 11, 2012

    More EPA….! More EPA…..! More EPA…….! More…!!!

    Now, I am sure EPA just not environmentalists community, but more than It : “Government Administration…”! You are successfully to open our problem, to see something how that important, to share public opinions, to answer people need and to bring the people calmly. Environmentalism seems to replace capitalism or socialism. Who knows????

  2. Cory Merriman permalink
    January 11, 2012

    When I was in college I participated in a wetland reclamation project. It was a blast, and was amazing to see everyone working together on it. Wetlands and swamps are among some of my favorite eco-systems. They provide so much beauty and bio-diversity. Swamps get kind of a bad rap but they are natures way of cleaning herself. In my mind there are so many things we can do to encourage better water quality, but it requires everyone being on the same page. Cooperation can get a lot accomplished but is difficult sometimes. Can’t wait to see what the many research projects find out. Thanks!

  3. Aaron@EPA permalink
    January 11, 2012

    Thanks Cory — sounds like important work and a great experience.

    Here is alink to some of EPA’s wetland research (good stuff!):

  4. kiyohisa tanada permalink
    January 12, 2012

    I think so “nitrogen” to be an important material on the earth.
    Without “nitrogen”, stability of the air disappears.
    It is convenient when I use “nitrogen” for “the tire of the car”.
    Besides, I am concerned with the thing that is important.
    Because I am near, I do not know “the important thing” well.
    I want to know more “nitrogen”.

  5. Gail permalink
    January 13, 2012

    Arman, I am confused. Is your assertion that EPA is becoming too big and needs to get out of people’s lives?

  6. Arman permalink
    January 15, 2012

    Dear Gail,

    No, it is not.-

  7. Steve Jordan permalink
    May 2, 2012

    The nitrogen problem can be difficult to understand. The nitrogen that makes up 70% of our atmosphere is in an inert form that has no effects on life, or chemistry for that matter. It is when the inert nitrogen is “fixed,” or converted into active chemical forms such as nitrate and ammonia, that it becomes (1) an essential nutrient for all life forms, and (2) a pollutant if there’s too much of it in the wrong places.

    The main sources of excess nitrogen are (1) combustion in power plants and automotive engines; (2) fertilizers; (3) human and animal wastes; (4) production of nitrogen-fixing crops, especially soy beans. Fixed nitrogen is a valuable and essential substance – it is when it’s wasted by overuse or lack of controls that it becomes a problem.

    Hope this is helpful.

  8. Sarah@EPA permalink
    May 3, 2012

    Steve, thank you so much for the clarification of these points. I neglected to explain the difference between inert versus fixed nitrogen in my post, but you did it very clearly here. It’s also important for us to be aware of these sources you point out that introduce excess nitrogen into our environment.

    Also, I’m happy to announce that EPA recently went live with a new website dedicated to explaining nutrient pollution:

    The site includes a thorough listing of EPA’s recent reports and current research related to nutrient pollution:

  9. August 8, 2012

    Steve Jordan, thanks a lot for explaining!
    It really makes sense and in the end it is again human’s fault that excess nitrogen posts a threat to us and other living creatures.

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