Department of Agricultural Economics and Rural Development
Economic, Environmental, and Health Effects of GM Crops
Matin Qaim
Keynote Lecture, 19th ICABR Conference16-19 June 2015, Ravello, Italy
Department of Agricultural Economics and Rural Development
GM crops: controversial topic
The public and policy debate is primarily focused on risks
In the EU and elsewhere, regulatory procedures were put in place treating GMOs very differently from other technologies
However, 30 years of research and 20 years of commercial experience have shown that GM crops are not inherently more risky than conventionally bred crops
This conclusion was drawn by Science Academies from all over the world and by International Organizations such as WHO, FAO, EU Research Directorate etc.
The public has not taken note of this scientific evidence
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Department of Agricultural Economics and Rural Development
Beyond risks, what do we know about GM crop impacts?
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Department of Agricultural Economics and Rural Development 4
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
0
20
40
60
80
100
120
140
160
180
Mil
lio
n h
a
Total
Industrialized countries
Developing countries
Global adoption of GM crops
Source: James (2014).
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Which countries? (>0.1 million ha)
Industrialized countries: USA, Canada, Australia, Spain
Developing countries: Brazil, Argentina, India, China, Paraguay, Pakistan, South Africa, Uruguay, Bolivia, Philippines, Burkina Faso, Myanmar, Mexico, Colombia, Sudan
Which GM crops/traits?
Herbicide tolerance (HT): soybean, maize, canola, alfalfa, sugarbeet
Insect resistance (Bt): maize, cotton (partly stacked with HT)
Department of Agricultural Economics and Rural Development
Impact studies
Many impact studies carried out over the last 20 years: Focusing on different countries With different types of data With different methodologies With different results
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GMO supporters and opponents refer to their “preferred studies” in the debate, leading to further polarization
Meta-analysis can be useful to: Draw broader lessons from the cumulated evidence Explain reasons for heterogeneity in impacts
Department of Agricultural Economics and Rural Development
Meta-analysis of GM crop impacts
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Klümper and Qaim (2014, PLoS ONE)
Crop
yield
(n=4
51)
Pestic
ide q
uant
ity (n
=121
)
Produ
ction
cos
t (n=
115)
Farm
er p
rofit
(n=1
36)
-60-40-20
020406080
21.6***
-36.9***
3.3
68.2***
Per
cen
t
*, **, *** means significant at the 10%, 5%, and 1% level, respectively.
Department of Agricultural Economics and Rural Development
Distribution of GM yield effects
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0.0
05.0
1.0
15.0
2D
ens
ity
-50 0 50 100change in yield (%)
Source: Klümper and Qaim (2014).
Department of Agricultural Economics and Rural Development
Meta-analysis
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(1) All GM crops
(2) Insect resistance
(3) Herbicide tolerance
Yield 21.6*** 24.9*** 9.3**
Pesticide quantity -36.9*** -41.7*** 2.4
Pesticide cost -39.2*** -43.4*** -25.3***
Total production cost 3.3 5.2** -6.8
Farmer profit 68.2*** 68.8*** 64.3
Source: Klümper and Qaim (2014).
Breakdown by type of technology
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Breakdown by geographical regions
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YieldPesticide quantity
Pesticide cost
Farmer profit
Developing country (dummy)
14.17*** -10.23 -19.16*** 59.52***
N 451 121 193 136
Meta-regression results (percentage point effects)
Source: Klümper and Qaim (2014).
Developing-country farmers benefit more from GM crops:
1. Because they suffer more from pest and disease problems
2. Because most GM technologies are not patented there, so that seed prices are cheaper than in developed countries
Department of Agricultural Economics and Rural Development
Aggregate global effects
The aggregate farm level benefits of GM crops at the global level were estimated at 20.5 billion US$ in 2013 (Brookes and Barfoot, 2015)
GM technology adoption has contributed to a 24% reduction in pesticide environmental/ health impacts
HT has reduced GHG emissions due to reduced tillage (less fuel use, more carbon sequestration in soils)
Due to weed resistance to glyphosate, some of the environmental benefits of HT crops have been decreasing recently (not yet an issue for Bt)
Without GM yield advantages, 25 million ha of additional farmland would have been required
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Department of Agricultural Economics and Rural Development
2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 20120
2
4
6
8
10
12
Mil
lio
n h
a
12
Bt cotton adoption in India
In 2014: 11.6 m ha (95%)
Grown by around 8 million smallholders
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Impact analysis with panel data
Survey of 530 farm households in:
• Maharashtra
• Andhra Pradesh
• Karnataka
• Tamil Nadu
Survey carried out four times between 2002 and 2009
Statistical differencing techniques to control for biases
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Bt impact on insecticide use
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Conventional 2002-2004
Bt 2002-2004 Bt 2006-2008 Conventional 2006-2008
0
0.5
1
1.5
2
2.5
3K
g o
f a
cti
ve
in
gre
die
nt
pe
r a
cre
Source: Krishna and Qaim (2012).
Department of Agricultural Economics and Rural Development
Bt impact on yield and farmer profit in India
15
Yield (kg/ha)
Profit($/ha)
Bt effect311***(+24%)
94***(+50%)
Change over time 0 / + 0 / +
Sources: Kathage and Qaim (2012), Qaim and Kouser (2013).
Household consumption value (US$)
Calorie consumption (kcal/person)
Calories from high-value food (kcal/person)
Bt effect 321**(+18%)
145***(+5%)
47***(+7%)
Bt impact on household living standard
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Household income effects per ha of cotton
0
100
200
300
400
500
600
-Extremely poor Moderately poor Non poor
All households
Bt
Conventional
US
$/ha
$246/ha
x 11.6 m = $2.9 billion Source: Subramanian and Qaim (2010).
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Sources: Kathage and Qaim (2012), Qaim and Kouser (2013).
Total Tox I Tox IITox III &
IV
Bt effect (2002-2004) -1.11*** -0.56* -0.49* -0.06
Bt effect (2006-2008) -1.79*** -1.08*** -0.66*** -0.06**
Environmental and health effects of Bt
Effects on pesticide use by toxicity class (per acre)
Source: Kouser and Qaim (2011),
Cases per acre Cases in total India (million)
Bt effect -0.104*** -2.98***
Effects on cases of acute pesticide poisoning
Department of Agricultural Economics and Rural Development
Effects on varietal diversity
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Farm level Village level District level State level0
5
10
15
20
25
30
35
2002 2004 2006 2008
Nu
mb
erMean number of cotton varieties grown by sample farms
Source: Krishna, Qaim, Zilberman (2015).
Department of Agricultural Economics and Rural Development
Future prospects Evidence suggests that GM crops contribute to sustainable
development (economic, social, environmental)
Effects differ by type of technology and context. The range of commercialized GM crops still limited
Future technologies are even more promising
Many interesting GM technologies tested in the field:
Drought-tolerant and salt-tolerant maize, rice, and wheat
Maize and rice with higher nitrogen use efficiency
Micronutrient-rich rice, sorghum, cassava, and banana
Pest- and disease-resistant rice, cassava, pulses, vegetables
Etc.
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…Future prospects
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Will these promising technologies ever make it through all the regulatory and societal hurdles?
As for any transformative technology, there are certain issues that need to be addressed, e.g.:
Market power
Seed market infrastructure
Unsustainable agricultural practices
But technology bans are hardly the best answer. More sensible regulation and better policies are required
Further reading:Qaim, M. (2015). Genetically Modified Crops and Agricultural
Development. Palgrave Macmillan (to be published in Nov. 2015).