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The IMPACTS OF GENETICALLY ENGINEERED CROPS ON PESTICIDE Use in the U.S. tHe first sixteen years

Implications of GM-Crop Cultivation at Large Spatial Scales Bremen, Germany June 14-15, 2012. Charles Benbrook, PhD Center for Sustaining Agriculture and Natural Resources Washington State University Pullman, WA.

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The IMPACTS OF GENETICALLY ENGINEERED CROPS ON PESTICIDE Use in the U.S. tHe first sixteen years

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  1. Implications of GM-Crop Cultivation at Large Spatial Scales Bremen, Germany June 14-15, 2012 Charles Benbrook, PhD Center for Sustaining Agriculture and Natural Resources Washington State University Pullman, WA The IMPACTS OF GENETICALLY ENGINEERED CROPS ON PESTICIDE Use in the U.S. tHe first sixteen years

  2. Remarkable Commercial Success Stephen Duke, ARS/University of Mississippi, and Michael Owen, of Iowa State University on glyphosate, herbicide-tolerant technology “…the most rapid adoption of a crop technology in the history of agriculture.” “…the most important change in technology in the history of agriculture.”

  3. Percent of National Acres Planted to Herbicide-Tolerant (HT) and Bt Transgenic Crop Varieties, 1996-2011 Percent of Acres Bt Corn for CRW HT Corn Bt Corn for ECB HT Soya HT Cotton Bt Cotton

  4. Roundup Ready (RR) Technology Largely Solved Difficult Weed Management Challenges in the Mid-1990s

  5. The Creation of a Multi-Billion $$ Seed-Biotech-Pesticide-Industry • Changes in U.S. patent and intellectual property law created unprecedented profit opportunities • The pesticide industry took over the seed industry, in the late 1980s – 1990s • In March 1999, DuPont purchased the remaining shares of Pioneer Hi-Bred International for $7.7 billion, an 80% premium over the stock’s trading value

  6. ? Conventional Wisdom • Dozens of papers in peer-reviewed journals assert GE crops reduce pesticide use, either based on no data or proprietary surveys of “representative fields” • Prominent scientists repeat the claim in professional meetings and policy venues • Lack of independent analyses by government or university experts allows industry claims to go unchallenged, despite growing evidence to the contrary

  7. Analysis based on USDA-NASS ‘Agricultural Chemical Use Surveys’. Calculated pounds applied per acre planted to conventional varieties and GE varieties. Reported a 122 million pound (55.3 million kg) increase 1996 – 2004.

  8. November 2009 report by The Organic Center. Herbicide use up 383 million pounds (173 million kgs) in first 13 years of GE crop use. Insecticide applications down 64.2 million pounds (29.1 million kgs). Overall pesticide use up 318 million pounds (144 million kgs).

  9. Analysis Now Updated Through 2011 • New USDA-NASS pesticide use data released for corn and cotton and 2010 • Update reflects the enormous impacts of glyphosate-resistant weed problems on herbicide use

  10. GE Crop-Pesticide Use Simulation Model • Linked series of 15 tables in an Excel workbook • Widely accepted USDA data available on: • Acres planted to maize, soybeans, and cotton • Percent crop acres planted and not planted to major GE traits • Herbicide and glyphosate use rates per acre • Use rates of insecticides displaced by Bt corn and cotton

  11. GE Crop-Pesticide Use Simulation Model • By crop, major GE trait, and year, the model estimates: • Herbicide use on acres planted to herbicide-tolerant and non-GE varieties, and hence differences in rates • Insecticides per acre not applied as a result of planting Bt corn or cotton • Impacts of GE traits on pesticide use across all acres planted to GE crops by year, and from 1996 through 2011

  12. ? Uncertainties in ModelProjections How weed management systems would have evolved in the absence of HT technology Design and efficacy of corn IPM systems for European corn borer and corn rootworm control if Bt crop technology had not become available

  13. ? Uncertainties in ModelProjections Method used to estimate “Other [not glyphosate] Herbicide” applications on HT acres by crop/year

  14. Estimating the Differences in HT and Non-HT Herbicide Use Solve weighted average equation for “Non-HT Rates”: Average herbicide use (kg/ha) = (% Hectare planted HT x HT rate) + (% Hectare Planted Non-HT x Non-HT rate) Five variables – 3 known, 1 easy to estimate (“HT Rate”), so the equation can be solved for fifth variable (“Non-HT Rate”)

  15. Key Results: 2011 Herbicide Rates • Each acre planted to a HT variety required substantially more herbicides than acres not planted to HT crops: • 0.73 pounds per acre more in the case of soybeans • 0.41 pounds per acre in corn • 0.86 pounds per acre in cotton C. Benbrook. 2012 “Impacts of Genetically Engineered Crops on Pesticide Use in the U.S. – The First Sixteen Years,” Environmental Sciences Europe, Pending.

  16. Impacts of HT Crops on Herbicide Use: 1996 - 2011 • Herbicide-tolerant (HT) crops have INCREASED herbicide use by a total or 527 million pounds (239 million kgs) • HT soybeans account for 72% of the total increase in herbicide use across the three HT crops

  17. Bt Crop Impacts on Insecticide Use and Overall GE Crop Impacts: 1996 - 2011 • Bt corn and cotton have REDUCED insecticide use by 124 million pounds (56 million kgs) • GE crops have INCREASED overall pesticide use by 403 million pounds (183 million kgs) • Represents, on average, an additional ~0.25 pound (~0.28 kg/ha) of active ingredient for every GE trait acre

  18. Changes in the Rate per Crop Year of Glyphosate (Roundup)

  19. Impacts of Bt Corn on Endotoxin Production Bt Corn Gene Expression Levels

  20. Impacts of Bt Corn on Endotoxin Production

  21. Bt Corn for ECB Endotoxin Production Compared to Insecticides Displaced • ~0.12 pound insecticides applied per acre for ECB control in 2010 • MON 810 produces 0.18 pound endotoxins per acre • Bt 11 produces 0.25 pounds endotoxin per acre • Dow/Pioneer Herculex TC1507 produces 0.097 pound per acre • MON 89034, Cry1A.105 plus Cry2Ab2 produces 0.6 pound of two endotoxins per acre (5-X insecticides displaced)

  22. Bt Corn for Rootworm Control Endotoxin Production Compared to Insecticides Displaced • ~0.19 pound insecticides applied per acre in 2010 • MON 88017, Cry3Bb1 produces 1.7 pounds endotoxin per acre • Dow/Pioneer DAS 59122-7, Cry34Ab1 plus Cry35Ab1 produces 2.5 pounds per acre (13-X insecticides displaced)

  23. On Fields Planted to Monsanto-Dow AgroSciencesSmartStax Corn • Each plant expresses six different Bt Cry proteins, three for ECB/Lepidoptera, and three for corn rootworm (CRW)/Coleopteracontrol • Total expression of Bt proteins is 3.73 pounds per acre: 12-times more than the insecticides displaced (0.31 pounds active ingredients [0.12 ECB + 0.19 CRW pounds])

  24. ? What About Bt CropEndotoxin ProductionCompared to Natural Levelsof Bt in the Soil Bt cotton produces up to 4,000 times more Bt than soil microorganisms, while Bt corn produces up to 16,800 times more. Blackwood, C.B., J.S. Buyer, 2004. “Soil Microbial Communities Associated with Bt and Non-Bt Corn in Three soils,” J. Environmental Quality, Vol. 33, pages 832-836

  25. The Resistance Clock is Ticking “You guys are three years behind us. This is exactly what we looked like three years ago.” Message to Iowa HT corn-soybean farmers from Jason Northsworthy, University of Arkansas weed scientist, after inspecting row-crop fields in central Iowa

  26. HT Technology has Dramatically Accelerated the Emergence and Spread of Resistant Weeds • Over 14 million acres (5.6 million ha) in the U.S. are now infested with glyphosate resistant weeds • 22 weeds now resistant to glyphosate, and more than a dozen now pose an economic threat to U.S. farmers • Some weeds have evolved resistance via two or more mechanisms of resistance! • David A. Mortensen et al., “Navigating a Critical Juncture for • Sustainable Weed Management,” BioScience, Vol. 62, page 75

  27. Resistance Poses an Ominous Threat to U.S. Farmers • 108 biotypes of 38 weed species are simultaneously resistant to herbicides in 2 or more families of chemistry • 44% of multiple resistant weeds have appeared since 2005 • Common waterhemp in the U.S. is resistant to more than 20 currently marketed active ingredients, including glyphosate, ALS, and PPD herbicides. • David A. Mortensen et al., “Navigating a Critical Juncture for • Sustainable Weed Management,” BioScience, Vol. 62, page 75

  28. Waterhemp Resistant to Five Herbicide Modes of Action are Expected in 2012 • Few, if any, viable chemical options will remain • Non-chemical options are all costly and require significant system changes - • return to rotations • use of heavy tillage to bury weed seeds • planting of cover crops, and • mechanical cultivation and/or hand weeding

  29. No Major New Herbicide Mode of Action Commercialized in 20 Years * “…It is very unlikely that new herbicides with new modes of action will be available within ten to 15 years.” Michael D.K. Owen, 2011. “Weed resistance development and management in herbicide-tolerant crops: experiences from the USA,” J. Consumer Protection and Food Safety, Supplement 1, pages 85-89, doi \10.1007/s00003-011-0679-2 * Gerwick, “Thirty years of herbicide discovery: surveying the past and contemplating the future,” Agrow (Silver Jubilee Edition)

  30. So…Industry Push to Market 2,4-D, Dicamba, and Paraquat HT Crops High-risk gamble for farmers and public health Five weed scientists on second-generation HT crops: “…we expect that synthetic auxin-resistant (2,4-D, dicamba) cultivars will be embraced by growers and planted on rapidly increasing areas in the US and worldwide over the next 5-10 years.” • David A. Mortensen et al., “Navigating a Critical Juncture for • Sustainable Weed Management,” BioScience, Vol. 62, page 75

  31. …and In Response to Claims that There are “Very Few” Weeds Resistant to Synthetic Auxins…. “Globally, there are 28 species [resistant to 2,4-D and dicamba], … and at least 2 resistant to both active ingredients.” “…the potential for synthetic auxin-resistant or combined synthetic auxin- and glyphosate-resistant weeds in transgenic cropping systems is actually quite high.” [Emphasis added] • David A. Mortensen et al., “Navigating a Critical Juncture for • Sustainable Weed Management,” BioScience, Vol. 62, page 75

  32. Dramatic Increase Highly Likely in 2,4-D Use Supplemental Table 19. C. Benbrook. 2012 “Impacts of Genetically Engineered Crops on Pesticide Use in the U.S. – The First Sixteen Years,” Environmental Sciences Europe, Pending.

  33. Basis for Projecting the Increase of 2,4-D Use on 2,4-D HT Corn (…if approved) • Dicamba-tolerant corn is not approved • 2,4-D HT corn adoption peaks at 55% in 2019 • Average rate of application increases from 0.35 pound in 2010 to 0.6 pounds (maximum 1.0 pound rate on label) • Number of applications increase from 1.1 to 2.3 in 2019 (maximum of 3 allowed on label)

  34. Drift and Volatilization of 2,4-D and Dicamba Even without 2,4-D HT crops, 2,4-D is the #1cause of crop damage episodes investigated by state departments of agriculture in the U.S. 2.4-D HT crops will vastly worsen problems because of higher rates and applications later in the crop season, despite the beneficial impact of the new Dow 2,4-D formulation

  35. Likely Problems in the Wake of Increases in Synthetic Auxin Herbicide Use Multiple studies link 2,4-D applications in the spring to reproduction problems, spontaneous abortions and birth defects Farm workers in California exposed to 2,4-D had a dramatically elevated risk of non-Hodgkin’s lymphoma (NHL) (odds ratio = 3.8), with female workers facing higher risks Paul K. Mills, Richard Yang, Deborah Riordan, 2005. “Lymphohematopoietic cancers in the United Farm Workers of America (UFW), 1988-2001,” Cancer Causes and Controls, Vol. 16, pages 823-830

  36. Emerging Issues in the Wake of GE Crop Technology Corporate control over the seed industry and germplasm – profits now drive breeding decisions in the U.S., not problem solving Passive role of the U.S. government in dealing with herbicide resistance and the collateral damage of HT crops Erosion of investments in prevention-based IPM and farmer IPM skill sets Rapidly growing reliance on systemic delivery of toxins – seed treatments, insecticides, Bt endotoxins – that alter risk profiles

  37. The Lack of Independent Research on GE Traits and Systems GE seed “technology agreements” contain language to the effect that – “This seed is for commercial use by farmers growing crops, and may not be used for any research purpose or to compare performance to other corn/soybean/cotton varieties.”

  38. Plant Health is Clearly Eroding on Many Farms • Declining plant health triggered by changes in genetics, planting densities, and crop management during the GE crop era • 2010 – 11% corn was treated with fungicide (USDA - NASS data) • Less than 1% of corn acres were treated with fungicides in all previous NASS surveys

  39. ? Is Corn IPM Obsolete “Within the past 14 years, producers have transitioned from a traditional IPM paradigm (scouting, use of thresholds, and rescue treatments) to that of a less integrated and more insurance-based approach to insect management…” Michael E. Gray, 2011. “Relevance of Traditional Integrated Pest Management (IPM) Strategies for Commercial Corn Producers in a Transgenic Agroecosystem: A Bygone Era?” J. Agricultural and Food Chemistry, Vol. 59, pages 5852-5858

  40. Eight Reasons Bt Corn Has To Date Proven Incompatible with IPM • Prophylactic treatment not reliant on scouting and thresholds • Inability to target treatments to parts of fields with populations exceeding economic thresholds • Toxin expressed throughout the production season, and not just when insects are most vulnerable or actively feeding • Toxin expressed throughout plant, including tissues that are not fed upon by a target insect

  41. Eight Reasons BtCorn Has To Date Proven Incompatible with IPM • The technology is dependent on single, or closely related toxins, increasing risk of resistance and/or cross-resistance • High probability of sub-lethal doses of Btendotoxins in some corn plant tissues during parts of the season, increasing resistance risk • Technology marketed as a complete solution, downplaying the need for other tactics • Presence of Bt genes/toxins in most elite corn hybrids denies farmers the choice of a non-Bt

  42. Vulnerable GE Crops Require Higher-Risk and High-Cost Seed Treatment Mixing multiple active ingredients in seed treatments increases the risk of resistance emerging in a variety of soil borne insects and pathogens Nicotinyl seed treatments likely major risk factor for honey bee/pollinator Colony Collapse Disorder (CCD) Michael E. Gray, 2011. “Relevance of Traditional Integrated Pest Management (IPM) Strategies for Commercial Corn Producers in a Transgenic Agroecosystem: A Bygone Era?” J. Agricultural and Food Chemistry, Vol. 59, pages 5852-5858

  43. Lessons From the U.S. Experience with First-Generation GE Crops Excessive reliance on single tactics, and one herbicide, will increase the risk of resistance, lead to more intensive pesticide use, and raise costs and environmental impacts. Resistance management requires an active, science-driven government role, with requirements imposed as mandatory label conditions, backed up by meaningful enforcement.

  44. Lessons From the U.S. Experience with First-Generation GE Crops Expecting too much from GE technology is asking for trouble The impacts of GE technology will be determined by the overall health of the agricultural system in which it is deployed

  45. A Criticl Insight From a Seminal 1997 PNAS Paper “As spectacular and exciting as biotechnology is, its breakthroughs have tended to delay our shift to long term, ecologically based pest management because the rapid array of new products provide a sense of security just as did synthetic pesticides at the time of their discovery in the 1940s.” Lewis, W.J. et al., 1997. “A total system approach to sustainable pest management,” Proceedings of the NAS, Vol. 94, pages 12243-12248

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