Economic and Health Impacts of GM Crops in China, India, and South Africa

Carl E. Pray Professor II

Agricultural, Food, and Resource Economics Department School of Environmental and Biological Sciences

Rutgers University pray@aesop.rutgers.edu

What has Biotechnology Contributed to Small Farmers’ Welfare in Asia & Africa?

•  Bt cotton production –  China 7 million small farmers –  India 5 million farmers –  Small numbers South Africa and Burkina Faso

•  Bt maize production –  Bt yellow maize 200,000 small farmers in Philippines –  Bt white maize – 1,000s of small farmers in South

Africa •  RR maize production – 1,000s of small farmers

in South Africa •  Little impact on other major subsistence food

crops such as rice and wheat

Today impacts on farmers based on three sets of studies

•  Bt cotton in China –  Huang Jikun, Hu Ruifa, Scott Rozelle and number of CCAP and Rutgers

students –  1999, 2000, 2001, 2004, 2006, and 2007 –  Up to 500 farmers in northeast and central cotton zones

•  India – Bt cotton –  Bharat Ramaswamy, ISI, Delhi, N.Lalitha, Gujarat Institute of Development

Research –  2004 and 2007 –  400 farmers Gujarat and Maharashtra

•  South Africa Bt and RR maize –  Marnus Gouse &Johann Kirsten U of Pretoria, John Rheeder, Medical Research

Council of South Africa –  Colin Thirtle, Imperial College, London; Jenifer Piesse, King’s College, London;

and Colin Poulton, U. of London. –  2001-4, 2006/07,2007/08 –  250 farmers in KwaZulu Natal province

•  Quality of data improved over time - more visits per year & larger samples

Summary of Insect Resistant Cotton Results

•  Increased net income of small farms – •  Either saving in pesticide use – China •  Increased yields – India •  Results vary by pest attack -

•  When pesticide use reduced, farmers do not get sick as much

•  Bollworms developing resistance? •  No empirical evidence in careful monitoring China •  In China evidence that bollworm population reduced with

benefits to other crops such as maize and vegetables •  Secondary pests emerging because Bt adoption has reduced

spraying of broad spectrum pesticides

Summary of Insect and Herbicide Tolerant Corn in Small Farms South Africa

•  White corn in ZA is first major subsistence food crop •  Insect resistance

–  Higher yields than conventional in years when stalk borer present – but not so often in some villages

–  Little change in insecticide use – did not use much in conventional corn

–  Reductions in exposure of rural consumers to mycotoxins which are associated with cancer and birth defects

•  Herbicide tolerance - preliminary data –  Increased yields –  Small reduction in labor use

CK transgenic

Bollworm Damage

Bt Cotton Spreads Rapidly in China

Yields Slightly Higher and Less Variable

Costs Down, Income Up (RMB/ha)

Pesticide Use Declines (Henan Villages 1999-2006)

Pesticide Poisonings Down

Unintended consequences of widespread Bt cotton adoption

•  Bollworm populations in Northern China have dramatically declined in cotton, corn, soybeans and vegetables 1997 – 2006 (Wu et al Science Sept 19, 2008) –  Bt cotton adoption is major determinant of decline –  Less damage & need to spray pesticides in these crops –  Bt cotton seems act as a trap crop –  No official refuge policy – alternative hosts have acted as refuge

•  Reduction in application of broad spectrum pesticides leads to increased damage from secondary pests –  Mirids an increasing problem in some areas leading to increased

use of pesticides for these pests –  Total pesticide use still down…

Source: Seed Industry

Major impact on yields

Pesticide Use Down – Maharashtra

Pesticide Use Up in Gujarat 2007 (applications per plot)

Revenues, Cost Bt Cotton Gujarat 2004 (Rs/acre)

South Africa – Bt White Maize

•  White maize is first GM subsistence crop in LDC

•  Exports a major share of maize •  “mature” country in first generation traits

– Bt and RR cotton – Bt yellow and white maize – RR yellow and white maize – RR soybeans

•  All from multinational corporations

Spread of GM Maize S.Africa (Area in ha)

Bt maize yields smallholders S.Africa

2001/02 – relatively high stalk borer infestation

32%

2002/03 – lower pressure = 16% in KZN (Hlabisa and Simdlangentsha) 2003/04 – no borers - no benefit 2006/07 – no borers – no benefit 2007/08 – high borer infestation – major benefits

Impact of RR Maize on Smallholders Hlabisa 2006/7

•  Higher yields (means) and great total efficiency (stochastic frontier model)

•  Modest reduction in labor use with RR (RR farmers also used minimum tillage which is labor intensive)

•  Seed costs double, herbicide costs up from nothing to 600 Rand/ha.

•  Gross margin (value output - cost of intermediate inputs) –  Rand 4738/ha RR –  Rand 1876/ha Bt –  Rand 1886/ha Conventional

Bt corn and mycotoxin reduction

•  Insects primary cause of fungal disease on corn –  Primarily pre-harvest damage –  Kernel damage; insects as

vectors –  European corn borers directly

linked to mycotoxins on US experiment stations (Dowd 1998)

•  Bt corn can reduce mycotoxins –  Less insect pest damage –  Less opportunity for growth of

fungus

Fumonisin: Health effects

•  1988 discovery: drought year - horse deaths •  Produced by Fusarium verticillioides, F. proliferatum •  Postulated human health effects

–  Oesophageal cancer: statistically associated with fumonisin in maize in Eastern Cape

–  Neural tube defects: high levels in E. Cape & Limpopo but no statistical association yet

•  Animal effects –  Equine leukoencephalomalacia (disease of central

nervous system) –  Porcine pulmonary edema (heart disease) –  Liver, kidney cancer in rodents

Fumonisin levels (ng/g or ppb) in maize in rural KwaZulu-Natal during 2004-2007

Potential Reduction of Exposure to Fumonisin if Bt Maize Adopted

•  Safe levels WHO-FAO 2 µg per kg of body weight per day