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Nutrient Pollution

The Sources and Solutions: Fossil Fuels

line of cars stuck in traffic
Cars and trucks release nitrogen into the atmosphere, which contributes to nutrient pollution in our air and water.

Airborne nitrogen pollution affects not only the quality of the air we breathe, but also the land and the water. Nitrogen is the most abundant element in the air and is essential to plant and animal life. Sources of nitrogen from human activities, such as electric power generation, industry, transportation and agriculture, can upset the natural balance of nitrogen in the environment.

When fossil fuels are burned, they release nitrogen oxides into the atmosphere, which contribute to the formation of smog and acid rain. The most common nitrogen-related compounds emitted into the air by human activities are collectively referred to as nitrogen oxides. Ammonia is another nitrogen compound emitted to the air, primarily from agricultural activities, but also from fossil fuels. Most of the nitrogen oxides released in the U.S. due to human activity are from the burning of fossil fuels associated with transportation and industry.

aerial view of traffic on city road covered in smog
When fossil fuels are burned, they release nitrogen oxides into the atmosphere, which contribute to the formation of smog and acid rain.

Major sources of nitrogen oxide emissions include:

  • Cars and trucks
  • Coal-fired power plants
  • Large industrial operations
  • Ships and airplanes

The presence of excess nitrogen in the atmosphere in the form of nitrogen oxides or ammonia is deposited back onto land, where it washes into nearby water bodies. These excess nutrients contribute to pollution, harmful algal blooms and oxygen-deprived aquatic zones. Excess ammonia and low pH in these areas are toxic to aquatic organisms and affect their survival.



There are many ways that businesses can reduce nutrient pollution, including:

  • Manage and Reduce Emissions
    Leading businesses are taking steps to understand and manage their greenhouse gas emissions by preparing annual greenhouse gas inventories and setting long-term targets to reduce emissions.
  • Increase Energy Efficiency
    Improving energy efficiency not only reduces greenhouse gas emissions into the atmosphere, it is good for a corporation's bottom line. Developing and implementing an effective corporate energy management program allows companies to manage energy with the same expertise used to manage other aspects of their business.
  • Buy Renewable Energy
    Your organization's purchased electricity use can be a significant source of air pollution and greenhouse gas emissions. Buying renewable energy, can help reduce your organization's environmental impact while also providing a number of other valuable benefits.


  • Conserve Energy
    Air pollution from energy production leads to acid rain, excess greenhouse gases, and health risks. One important step you can take to minimize airborne nutrient pollution is to conserve energy. You can do this by:
    • Turning off lights, computers, televisions, video games and other electrical equipment when you're not using them.
    • Buying equipment that uses less electricity, including lights, air conditioners, heaters, refrigerators and washing machines. Energy Star-certified products and buildings use at least 10 less energy than standard models.
    • Limiting the use of air conditioning.
    • Installing a programmable thermostat.
  • Minimize the Miles
    Driving cars and trucks also produces significant amounts of nitrogen oxide emissions. To help cut down on air pollution from cars, you can consolidate driving trips, carpool or take public transportation, such as buses and trains. When possible, consider walking or biking instead of driving.