Some explosives in your salad?

by Lila Rimalovski, Student in SEE-U NYC: Agro-eco/Food Systems Course

Guisante, a nitrogen-fixing legume that can be used as a cover crop to decrease the need for synthetic fertilizers. Photo by Lila Rimalovski, taken at an organic farm in Spain

There are two tales in modern global history that are more similar than you’d think: one is the story of wartime explosives, the other is the story of industrial agriculture. The point of intersection between these two boils down to a seemingly invisible yet ever-present facet of life: nitrogen.

Nitrogen is one of the core building blocks for all living things on Earth; everything from microorganisms to humans to entire ecosystems relies on this one element for survival. Edible crops demand high amounts of nitrogen inputs (what we call fertilizer), which means that the success of our agricultural systems is entirely reliant on the available supply of nitrogen. Nitrogen is also widely used in metal manufacturing, oil refineries, and, important to this narrative, in ammunition and explosives. In short, our economies, governments, farms, and communities are dependent on nitrogen to maintain our ways of life. Here’s the catch: 78% of our global nitrogen supply is suspended in the atmosphere, existing in a chemical form that is inaccessible to humans and most other life forms (Erisman et al., 2008).

So, if everyone needs it, yet so few can access it, how we are harnessing the nitrogen we use in everyday life?

This is the question that inspired the greatest achievement of a German scientist named Fritz Haber. In October of 1908, Haber discovered how to transform atmospheric nitrogen into a usable form called ammonia. This process, which he received a Nobel Price for, involves synthesizing atmospheric nitrogen with hydrogen and iron in the presence of high pressures and temperatures. While Haber’s discovery was revolutionary, he had not yet figured out how to implement the process on an industrial scale. Thus, Carl Bosch entered the scene. Also a German scientist, Bosch was able to revolutionize the impact of Haber’s discovery by massively increasing the scale at which the process could occur. The combination of Haber’s mad science with Bosch’s real-world expansion dubbed them the fathers of the chemical reaction, resultantly naming their joint creation the Haber-Bosch Process (Erisman et al., 2008).

The immediate application of the Haber-Bosch Process arose in the First World War. As German supplies of ammunition were decreasing while the demand was increasing, Haber and Bosch created a seemingly unlimited supply of available nitrogen—the key ingredient in ammunition—just as the Germans were looking for more deposits. Haber and Bosch supplied the Germans with the primary tool to produce ammonium nitrate, nitroglycerine, TNT, and other nitrogen-containing explosives. Since then, the Haber-Bosch Process has been utilized in wartime weapon production throughout the 20^th century yielding an estimated 100-150 million war-related deaths (Erisman et al., 2008).

As Haber and Bosch were igniting global warfare, literally, they were also helping us grow food like we never had before. Due to the high nitrogen inputs required for large-scale agriculture, the Haber-Bosch Process provided an immediate and accessible source of food for our crops, therefore feeding our increasing population. Agronomists posit that the number of humans supported per hectare of arable land rose from 1.9 in 1908 to 4.3 people in 2008—more than doubling the number of humans sustained by the same piece of land (Erisman et al., 2008).

Here arises the dilemma: the Haber-Bosch process was feeding us as it was killing us, while simultaneously destroying our environment in ways that neither scientist had predicted. One of the most significant consequences arose in the amount of leachate from farms applying high amounts of nitrogen fertilizer. The excess nitrogen leaving the farms entered other pools in the ecosystem, exacerbating water pollution, extreme loss of biodiversity, and eutrophication. The prominence of industrial agriculture increased with the availability of Haber-Bosh nitrogen, therefore contributing to increased air pollution, perturbation of greenhouse-gas levels, soil acidification, formation of particulate matter in the atmosphere, among many, many more consequences (Erisman et. al., 2007).

So, do the repercussions of the Haber-Bosch process outweigh the benefits? Is feeding our population efficiently and effectively, albeit through harmful practices, better than not doing it at all? And how do we, consumers, make sense of the relationship between the agriculture that sustains us, and the explosives used by our military?

The answer to these questions lies in the arrangement of our priorities as human a population—what comes first, global health, war, or capitalism?

References

Erisman, J.W., Bleeker, W., Galloway, J., Sutton, M.S., 2007. Reduced nitrogen in ecology and the environment. Environ. Pollut. 150, 140-149.

Erisman, J.W., Sutton, M.S., Galloway, J., Klimont, Z., Winiwarter, W., 2008. How a century of ammonia synthesis changed the world. Nat. Geosci. 1, 636–639.

Stewart, W. M., Dibb, D. W., Johnston, A. E., Smyth, T. J., 2005. The Contribution of Commercial Fertilizer Nutrients to Food Production. Agron. J. 97, 1-6.