Regional Nuclear War
in South Asia:
Effects on Surrounding Countries
Nicholas Wilson, MBChB, FAFPHM, MPH†
The potential effects of nuclear wars involving India, Pakistan, and China on neighboring non-combatant countries and the rest of the world are estimated by applying
historical data on nuclear weapons effects and models for nuclear weapons usage to
a range of plausible war scenarios involving these three countries. Lethal levels of
local radioactive fallout could reach neighboring countries such as Nepal and
Bangladesh after nuclear attacks on India. After an India-China conflict, radiation
could spread globally and the external radiation alone might be expected in the longterm to cause around 0.6 million cancer deaths in the population living in latitudes 20
to 40 degrees North. Refugee flows, the spread of epidemics, and trade disruptions
could have even more severe effects on neighboring countries than the impact from
fallout. Nuclear weapon attacks on Pakistan, India, and China would have major
impacts on neighboring countries and could spread radioactive fallout globally.
Prevention of nuclear war through disarmament measures should be both a regional
and global priority. [M&GS 1999;6:24-27]
D
uring May 1998 both India and
Pakistan undertook a series of nuclear
weapons tests that dramatically
§ demonstrated their nuclear weapon
capabilities [1]. The current military situation
between these countries is relatively unstable
as there is major asymmetry in the size of
their nuclear arsenals, along with asymmetry
in conventional military power. The absence
of sophisticated early warning systems and
† At the time of publication NW was a public
health physician and an independent consultant
to health organizations in Wellington, New
Zealand.
the very short warning times involved also
raise the risk of surprise first strike attacks. In
the last half of this century India has had
three major wars with Pakistan and one with
China [see Mian, Z., “The Politics of South
Asia’s Nuclear Crisis,” M&GS 1998;5:78-85];
current border disputes between India and
these other countries remain unresolved; and
both India and Pakistan have increased military spending [2]. Given this situation, it is
likely that this region poses the highest risk
of a future nuclear war in the world. Indeed,
the Bulletin of the Atomic Scientists considered
the developments in India and Pakistan as a
reason for moving the hands of their symbolic doomsday clock forward to nine minutes to midnight [3].
© Copyright 1999 Medicine & Global Survival
24 Medicine & Global Survival, August 1999; Vol. 6, No. 1
Regional Nuclear War
The following two nuclear war scenarios
are considered here (direct and indirect physical effects are based on scaling from the 1985
and 1986 SCOPE studies [4,5]) :
Methodology
ß An India-Pakistan war in
which 25 15-kiloton (kt) Hiroshimasized warheads are exploded on
Pakistani targets and nine similar
warheads are exploded on Indian
targets, 0.27 megaton (Mt) as airbursts, 0.24 Mt as surface bursts.
ß A China-India war involving
25 Hiroshima-sized explosions on
Chinese targets and 75 explosions on
Indian targets (an even mix of 100 kt
and 300 kt weapons; 7.5 Mt as airbursts, 7.9 Mt as surface bursts).
These scenarios represent around half
the Indian strategic arsenal (assumed to contain 50 strategic nuclear weapons) and
around three-quarters of the Pakistani arsenal (assumed to contain around 12 strategic
weapons [6]). There is significant uncertainty
surrounding the size of the weapons in these
arsenals given the seismological data from
recent weapons tests suggesting much smaller yields (less than Hiroshima-size) than the
official information released by the Indian
and Pakistani Governments [7]. China was
assumed to use 30% of its 250 strategic
nuclear weapons, which range from 100 kt to
300 kt for most long-range missiles (an average of 200 kt was used) [8]. The delivery systems assumed were aircraft for Indian and
Pakistani weapons and aircraft and ballistic
missiles for Chinese weapons [6].
As in a number of previous nuclear war
scenarios [4], this study assumed an equal
mix of air and surface nuclear explosions. In
addition to the scenarios developed, the
effect of the destruction of all of India’s 10
nuclear reactors (with a generating capacity
of 1,695 MWE [9]) was considered in terms of
its contribution to global fallout (based on a
previous reactor attack model [4]).
Arsenals and Delivery Systems
The levels and distribution of global fallout were based on scaling from the GLODEP
[2] model used in the study by the Scientific
Committee on Problems of the Environment
(SCOPE) [4]. This model produced doses
integrated over 50 years without assuming
anything about weathering or sheltering. A
50% fission fraction was assumed (as in the
scenario used by SCOPE) and the standard
risk factor for cancer mortality of 5% per sievert was used for estimating the radiation-
Fallout
Regional Nuclear War
induced cancer burden [10].
Results
An India-Pakistan War
Nuclear explosions of 15 kt over Indian
and Pakistani cities in this scenario would
probably kill far more people per city than
the 120,000 killed at Hiroshima [11]. This is
because of the larger and denser populations
of modern Asian cities and the higher level of
combustible materials and fossil fuels, which
increase the risk of firestorms. One estimate
for a 15-kt attack on Bombay suggested that
150,000 to 800,000 deaths would occur within
a few weeks [12]. Therefore, it is likely that
many millions of citizens in both countries
would die in the short term from the 34
explosions occurring in this scenario.
The destruction of many major cities in
the attacked countries would also be likely to
lead to social and political chaos disrupting
food production and distribution. This could
lead to famines, which may not be alleviated
by international aid measures in a turbulent
post-war international environment. Also, the
destruction of water and sewage systems
could increase the risk of disease epidemics
among the survivors. These indirect effects
could ultimately cause far more mortality
than the short-term effects, as has been previously predicted for larger nuclear wars [5].
Such effects could have an impact on neighboring countries, especially if there were large
migrations of refugees crossing country borders to escape famine, social chaos, or environments contaminated with radioactivity.
This nuclear war could cause immediate
deaths from radiation exposure in neighboring countries—depending on meteorological
conditions, which vary by season. Other
impacts on the neighboring countries could
Wilson 25
Figure 1. A
nuclear war
between India
and Pakistan or
between India
and China would
have health and
environmental
consequences
for the entire
South Asia
region, including
neighboring
countries
Bangladesh and
Nepal.
arise from exposure to sub-lethal local fallout
(increased long-term cancer risk), the disruption in cross-border trade of critical products
such as food, floods from destroyed dams,
and the movements of refugees across borders. Bangladesh would be particularly vulnerable to the consequences of a nuclear
attack on Calcutta, and Nepal would suffer
from attacks on northern Indian coastal cities.
Due to the relatively small size of the
nuclear weapons used in this scenario, there
would not be significant injection of radioactivity into the stratosphere. Hence this war
would not contribute significantly to global
radioactive fallout.
In this scenario the devastation on Indian
cities by the higher yield Chinese weapons
would
be
substantially
greater. For example, a 150-kt
attack on Bombay would be
Depending on wind
likely to cause between two
and six million deaths [12].
speed and direction,
Surface level nuclear explofallout plumes could
sions in this scenario would
extend from explosions contaminate even larger areas
of India than would be affecton Delhi and Calcutta
ed in an India-Pakistan
into the territories of
exchange. Short term deaths
non-combatant countries
Nepal and Bangladesh. in
such as Nepal and BanglaSuch plumes could be desh would also occur from
nuclear attacks on Indian
lethal to half the
cities. For example, a surface
exposed population of burst explosion of 300 kt produces a 300-square-km fallout
these two countries.
plume that delivers a 48-hour
whole-body dose of 450
centiGray. This would be
lethal to half the exposed adult population
[13]. Depending on wind speed and direction,
plumes could extend from explosions on
Delhi and Calcutta into the territories of
Nepal and Bangladesh respectively (e.g., with
the predominant southwesterly winds which
occur mid-year). By comparison, an estimated 53% of the total person-sievert exposure of
radioactivity from Chernobyl affected those
living in European countries outside the
Soviet Union where the disaster occurred [14].
In this scenario, which involves
weapons of 100 kt and larger, a proportion of
the fallout would be injected into the stratosphere and hence circulate the globe and
even cross the hemispheres. The global external gamma ray dose was estimated to peak at
4.6 milliGray (mGy) (at latitude 20 to 40
degrees North) in the Northern Hemisphere
and 0.003 mGy (at latitude 30 to 50 degrees
South) in the Southern Hemisphere. These
levels of radiation would be expected to
A China-India War
cause 230 fatal cancers per million population
in the latitude bands of the Northern
Hemisphere and 0.2 in the Southern
Hemisphere. For the 20 to 40 degree North
latitude, with a population of approximately
2.5 billion people, there would be an estimated 0.6 million radiation-induced cancer
deaths. However, only around 12% of this
dose would be delivered in the first 20 years,
with the rest being delivered over thousands
of years (based on the experience of atmospheric tests and the importance of carbon-14
as a radionuclide from these explosions [5]).
These levels of global fallout would only
be marginally increased if Chinese weapons
vaporised the contents of all India’s 10
nuclear reactors (i.e., adding an estimated 1.5
mGy to gamma ray doses from lower latitude
Northern Hemisphere fallout). Bombing
nuclear reactors, however, would dramatically increase the area contaminated with hazardous local fallout within the attacked country. For example, the explosion of a onemegaton bomb on a one-gigawatt reactor has
been estimated to cause a fallout plume
delivering total external gamma-ray doses of
100 centiGray per year around 530 km long
and up to 70 km wide [4].
This analysis indicates that plausible
types of nuclear wars involving Pakistan,
India, and China would have catastrophic
impacts on these countries that would rival
the previous worst disasters they have experienced. These include the 1876-1877 famine
in India that affected 20 million and killed 3.5
million [15] and the 1958-1961 famine in
China that caused an estimated 30 million
premature deaths [16].
The global fallout distribution model
used in this analysis has a number of limitations, including being based on limited data
on Northern Hemisphere explosions in midlatitudes [4]. The assumptions that there
would be no weathering and no sheltering
lead to an over-estimation of the exposure
level since weathering is important in most
environments and a majority of humans
spend most of their lives indoors. These estimates of radiation exposure are probably
conservative, however, since the effects of
internal radiation dosage are not included
and since these would probably be more
important than external radiation in the long
term [7]. Moreover, low-level radiation exposure might be significantly more hazardous
than the estimate used in this analysis [17,18].
If the nuclear arsenals of these countries
increase in size and in average weapon yield
in the future, then multiple attacks on cities
would become more likely in future war sce-
Discussion
26 Medicine & Global Survival, August 1999; Vol. 6, No. 1
Regional Nuclear War
narios. This would further increase the risk of
firestorms in cities suffering nuclear attack,
which would increase the probability of toxic
and radioactive debris reaching adjacent
countries. It would also pose greater risks of
regional climatic disturbances arising from
nuclear war.
Adverse economic effects on neighboring countries would arise from disruption in
cross-border trade, floods from destroyed
dams, and the movements of refugees across
borders. These impacts could be further exacerbated if there were cross-border radioactive
contamination of primary agricultural products produced for export. Such impacts could
damage trade for many years into the postwar period.
The use of weapons of mass destruction
is the very worst way for nations to solve
international disputes. Moreover, most forms
of nuclear weapons use are likely to be illegal
under international law [19] and damage to
non-combatant countries in war breaches
international law [20]. There is an urgent need
for nuclear disarmament to lower the risk of
such catastrophic nuclear wars. Progress
toward disarmament is unlikely, however,
without strong leadership by the United
States and Russia towards a verifiable and
enforceable Nuclear Weapons Convention
[21].
§
1. Albright D. The shots heard ‘round the
world. Bull Atomic Sc 1998;54:20-25.
2. Hoodbhoy P, Mian Z. Sanctions: Lift ‘em.
Bull Atomic Sc 1998;54:20-23.
3. Editorial. Nine minutes to midnight. Bull
Atomic Sc 1998;54:4-5.
4. Pittock AB, Ackerman TP, Crutzen PJ, et al.
Environmental Consequences of Nuclear War.
(SCOPE 28) Vol 1: Physical and Atmospheric
Effects. Chichester: John Wiley & Sons. 1986.
5.
Harwell
MA,
Hutchinson
TC.
Environmental Consequences of Nuclear War.
(SCOPE 28) Vol II: Ecological and Agricultural
Effects. Chichester: John Wiley & Sons. 1986.
6. Norris RS, Arkin WM. After the Tests: India
References
Regional Nuclear War
and Pakistan Update. Bull Atomic Sc
1998;54:69-71.
7. Barker B, Clark M, Davis P, et al. Monitoring
nuclear tests. Science 1998;281:1967-8.
8. Norris RS, Arkin WM. British, French, and
Chinese nuclear forces. Bull Atomic Sc
1996;52:64-67.
9. IAEA. Nuclear power status around the
world. IAEA Bull 1998;40(1):41.
10. Gonzalez AJ. Biological effects of low doses
of ionizing radiation: A fuller picture. IAEA
Bull 1994 36(4):37-45.
11. Harwell C (ed). Experiences and extrapolations from Hiroshima and Nagasaki. In:
Harwell MA, Hutchinson TC. Environmental
Consequences of Nuclear War. (SCOPE 28) Vol
II: Ecological and Agricultural Effects.
Chichester: John Wiley & Sons. 1986.
12. Ramana MV. Effects of a nuclear blast over
Bombay. Med Global Survival 1998;5:74-77.
13. Glasstone S, Dolan PJ (eds). The Effects of
Nuclear Weapons. Washington, DC: US
Department of Defense and US Department of
Energy. 1977.
14. United Nations Environment Programme.
Radiation: Doses, effects, risks. Oxford:
Blackwell. 1991.
15. Gibney E (ed). Disaster, when Nature
Strikes Back. New York: Bantam/Britannica
Books, 1978.
16. Ashton B, Hill K, Piazza A, Zeitz R. Famine
in China, 1958-61. Population Development Rev
1984;10: 613-645.
17. Fairlie I, Resnikoff M. No dose too low.
Bull Atomic Sc 1997;53:52-56.
18. Köhnlein W, Nussbaum RH. False alarm or
public health hazard?: Chronic low-dose external radiation exposure. Med Global Survival
1998;5:14-21.
19. Moore M. World Court says mostly no to
nuclear weapons. Bull Atomic Sc 1996;52:39-42.
20. Grief N. The World Court project on nuclear
weapons and international law. Northamton
Massachusetts: Aletheia Press, 1992.
21. Forrow L, Sidel VW. Medicine and nuclear
war: From Hiroshima to mutual assured
destruction to abolition 2000. JAMA
1998;280:456-61.
Wilson 27