World Medical Journal

The Growing Threat of Nuclear War and the Role of the Health Community

Ira Helfand, MD; Andy Haines, MD; Tilman Ruff, FRACP; Hans Kristensen; Patricia Lewis, PhD Zia Mian, PhD


January 03, 2017

In This Article

The Health Consequences of Nuclear War

Given the growing danger of nuclear war, it is important to consider the health consequences of such a conflict. It is not just large-scale nuclear war between the United States and Russia that poses a global threat. A series of studies have shown that localized, regional nuclear war will also have catastrophic effects worldwide.

The scenario that has been studied most frequently is a limited nuclear war between India and Pakistan involving 100 Hiroshima-sized warheads (small by modern standards) targeted on urban centers. (This is a deliberate underestimate of the full potential of war in South Asia: The combined arsenals of India and Pakistan actually contain more than 220 nuclear warheads.) The direct effects in South Asia are catastrophic. Some 20 million people would die in the first week from the direct effects of the explosions, fire, and local radiation.[11]

The global consequences—global climate disruption and resultant famine—would be far more devastating. The fires caused by these nuclear weapons would loft 6.5 million tons of soot into the upper atmosphere, causing significant drops in average surface temperature and average precipitation across the globe, with the effects lasting for more than a decade. [12,13,14]

This climate disruption would in turn have a profoundly negative impact on food production. The maize crop in the United States, the world's largest producer, would decline by 12% over a full decade.[15] In China, the world's largest producer of grain, middle-season rice production would decline by 17% over a full decade, maize by 16%, and winter wheat by a truly catastrophic 31%.[16]

Under current conditions, adequate human nutrition cannot be sustained in the face of declines of food production of this magnitude. Total world grain reserves in January 2016 amounted to only 84 days of global consumption, and would not begin to offset the shortfall over a full decade.[17] Furthermore, 795 million people are already undernourished at baseline.[18]

There are also some 300 million people who enjoy adequate nutrition today, but live in countries highly dependent on food imports, which would probably not be available as grain-exporting countries suspended exports to feed their own people. In addition, there are nearly a billion people in China with incomes of $5 a day or less who are adequately fed today, but who have shared little in China's growing prosperity over the past several decades. All of these people, around 2 billion, would be at risk under the potential famine conditions that would result from this limited, regional nuclear war.[19]

Large-scale war between the United States and Russia would be far worse. A 2002 study showed that if just 300 of the weapons in the Russian arsenal hit urban targets in the United States, 75-100 million people would die in the first half-hour from the firestorms and explosions.[20] This attack would also destroy most of the infrastructure—the electric grid, Internet, banking and public health systems, and food distribution network—needed to support the rest of the population, most of whom would succumb to exposure, starvation, and epidemic disease in the months following. A US counterattack would be expected to cause the same level of destruction in Russia, and if NATO were involved in the conflict, Canada and much of Europe would face similar destruction.

These direct effects are only part of the story, however. As is true for a limited war in South Asia, the global climate effects would be far worse. A war involving only the strategic weapons that will still be deployed when New START (Strategic Arms Reduction Treaty) is fully implemented would put some 150 million tons of soot in the upper atmosphere, and drop temperatures around the world by 8°C.

In the interior regions of North America and Eurasia, temperatures would fall by 25-30°C. These conditions would persist for more than a decade. Temperatures on Earth have not been that cold since the last ice age. In the temperate regions of the Northern Hemisphere, the temperature would fall below freezing for some portion of every day for at least 2 years.[21] Under these conditions, food production would stop and the vast majority of the human race would starve.


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