Reactive Nitrogen Fact Sheet
Impacts
US Environmental Impacts
- The number of low-oxygen dead zones is rising steadily, from 39 at the end of the 1960s to 530 “dead zones” in 2011.[3]
- Atmospheric deposition of nitrogen from fossil-fuel combustion is the largest single source of nitrogen pollution in much of the northeastern United States, leading to acid rain that contributes to the Chesapeake Bay dead zone.
- In the Mojave and Sonoran deserts of the southwestern U.S., non-native grasses like red brome thrive on atmospheric nitrogen pollution. The grasses provide dangerous fuel for wildfire and threaten native plant survival.[4]
- In California, invasive European grasses spurred by increased nitrogen emissions from auto exhaust are wiping out native wildflowers that don’t adapt to nitrogen-rich soil. [5]
Health Impacts
- Nitrogen oxides formed by fossil fuel combustion create ozone, otherwise known as smog. Tiny particles in smog damage lung tissue, increase the risk of cancer and cause heart disease. A recent 18-year study shows that long-term, low-level exposure to ozone can be lethal, increasing the yearly risk of death from respiratory diseases by 40% to 50% in heavily polluted cities like Los Angeles, California.[6]
- Health impacts from increased nitrogen pollution include the consequences of ozone pollution on asthma and respiratory function, and potentially increased allergies and asthma. High nitrate levels in drinking water elevate the risk of blue-baby syndrome and may also spell increased risk of cancer and other chronic diseases.[7]
Africa faces crises resulting from nitrogen deficiencies, as population growth and agricultural demands exceed the land’s ability to provide. But even in Africa, there are highly localized areas that suffer sewage disposal problems or runoff from synthetic fertilizer.
Image source: http://www.wri.org/project/eutrophication/gallery/images/sources
Global Impacts
- In Asia, the growing use of coal and other fossil fuels results in the growing release of nitrogen oxides to the atmosphere. China is now the world’s top user of synthetic fertilizers, applying 41 million tons in 2004, an 8 million-ton jump in just ten years. The number of dead zones along the Chinese coastline now equals those in North America and Western Europe.[8]
- In Latin America, the release of nitrogen into water supplies from inadequate sewage treatment threatens public health, while more rural areas grapple with agricultural runoff and the impacts on freshwater supplies and air quality that follow.
- Africa faces crises resulting from nitrogen deficiencies, as population growth and agricultural demands exceed the land’s ability to provide. But even in Africa, there are highly localized areas that suffer sewage disposal problems or runoff from synthetic fertilizer.
Reference
[3] World Resources Institute, Research Identifies 530 Coastal “Dead Zones” and 228 Marine Eutrophic Sites, Jan. 2011 (wri.org/press/2011/01/new-web-based-map-tracks-marine-dead-zones-worldwide)
[4] Alien grasses in the Mojave and Sonoran Deserts, ML Brooks, TC Esque, Proceedings California Exotic Plant Pest Council Symposium, 2000, (werc.usgs.gov/lasvegas/pdfs/Brooks_Esque_2000_Alien%20grasses%20in%20the%20Mojave%20and%20Sonoran.pdf)
[5] UCR, the magazine of UC Riverside, Spring 2008: Volume 3, Number 2, A Global Warning, link at (ucrmagazine.ucr.edu/cgi-bin/display.cgi?id=120)
[6] Low-level ozone exposure found to be lethal over time, by Thomas H. Maugh II, Los Angeles Times, March 12, 2009, (articles.latimes.com/2009/mar/12/science/sci-ozone12)
[7] California Watch, Coping with nitrate contamination, May 13, 2010, (californiawatch.org/coping-with-nitrate-contamination)
[8] UNEP and WHRC. Reactive Nitrogen in the Environment: Too Much or Too Little of a Good Thing. United Nations Environment Programme, Paris, 2007.