Bt Brinjal The scope and adequacy of the GEAC environmental risk assessment

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30 Bt Brinjal: The GEAC environmental risk assessmentsuffer greater damage than the less preferred host.Table 2. Host plants of BFSB, Leucinodes orbonalis, as reported inHowever, in real ecological conditions, all things are Waterhouse 1998never equal, and there are many circumstances whereHost Plant SpeciesAuthoritya less preferred plant is damaged more than the moreSolanum violaceum OrtegaMenon 1962preferred one. Thus, the suitable host range of BFSBSolanum viarum Dunel Dhankhar et al. 1982provides the best basis for understanding the effectsSolanum myriacanthumof gene flow on attack by BFSB. The suitable hostIsahaque and Chaudhuri 1983Dunal (shoots only)range of BFSB is quite broad (Table 2), and includesSolanum virginianum L.Menon 1962some plants not even remotely related to brinjal.Solanum nigrum L.Nair 1967; Das and Patnaik 1970;Thus, it must be concluded that the host range ofIsahaque and Chaudhuri 1983BFSB is not well known.Fletcher 1916; Mehto et al. 1980;Solanum tuberosum L. (shoots only)Moreover, the known host range of BFSBIsahaque and Chaudhuri 1983includes two species with which brinjal can hybridise.Hargreaves 1937;SSolanum lycopersicum L.Das and Patnaik 1970These are Solanum violaceum Ortega and SolanumCape gooseberryPillai 1922virginianum L. It is also likely that BFSB feedsGreen pea podsHussain 1925on wild populations of S. melongena, such as S.Mango shootsHutson 1930melongena var. insanum. All of these taxa couldCucumber, sweet potato, capsicum Whittle and Ferguson 1987obtain a fitness benefit from the Bt transgene, yetthese possibilities are not considered by EEII, theDossier, or the Supplemental Materials. Overall, the assessment of weediness is overly simplistic and ignores of the publishedliterature related to the problem.The aggressiveness study cited in EC-II is insufficient to assess weediness. The negative results from the aggressiveness testare inconclusive (Dossier, vol. 5), because there is no information about the level of seed deposition. It is not possible to knowif the negative results are due to the lack of aggressiveness of brinjal or because of the lack of seed deposition.Moreover, the results do not address the more serious potential aggressiveness associated with wild or feral populations ofS. melongena, such as S. melongena var. insanum. Because brinjal can form wild populations, the results from the aggressivenessstudy focusing only on cultivars may be misleading.There is no effort to determine if the genetic diversity of any of the wild relatives could be adversely affected. Hybridisationwith S. incanum occurs at significant enough rates that the threat to its genetic diversity should be considered. Effects on geneticdiversity of the recipient population are likely only when introgression is very high (Haygood et al. 2002, Ellstrand 2003).Thus, there is an a priori expectation that loss of genetic diversity is unlikely. However, empirical data coupled to a theoreticalunderstanding of the problem are needed to provide assurance that the a priori expectations hold in this case.There is also no effort to determine if Bt brinjal will contaminate non-GM brinjal, thereby affecting the quality of non-GMbrinjal. Several kinds of impacts need to be considered:• Organic brinjal production. Will contamination result in loss of organic status, classification or price?• Export brinjal. Will contamination affect the export demand for Indian brinjal?• Non-GM brinjal. Will the market for brinjal in India segment and will contamination affect the price of non-GM brinjal?Religiously significant brinjal. Will contamination compromise the sacredness of brinjal varieties with religious significance,such as udipigulla?• Culturally significant brinjal. Will contamination compromise the cultural value of brinjal, such as the brinjal used inwedding ceremonies?Needed Experiments and ObservationsField studies should be carried out to evaluate the risks of weediness and loss of genetic diversity (numbering is continued
Environmental Risk Assessment 31from previous section).8) Identify pests of wild relatives. Determine whether BFSB or other susceptible lepidopteran species feed on wild andweedy relatives of brinjal (S. melongena, S.melongena var. insanum, S. incanum, and other relevant species). Cohen et al.(2008) provide a sampling design for this type of study.9) Fitness advantage of Bt transgene. If lepidopteran larvae are present at any stage of the life cycle of these wild or weedyrelatives of brinjal, further studies should be carried out to determine whether a Bt transgene could enhance the survival orfecundity of wild/weedy plants under a variety of field conditions, thereby providing a fitness advantage. Snow et al. (2003)provide an experimental and sampling design for this type of study.10) Quantification of fitness advantage. If this is the case, the Bt trangene is likely become more common in wild orweedy populations that hybridise with the crop. Further studies could be carried out to evaluate whether the fitness advantageis large enough to result in more problematic weed populations, whether the expected ubiquity of Bt toxins in wild or weedypopulations could have unwanted effects on non-target lepidopteran insects, and whether the rapid spread of the Bt transgene(and linked crop genes) would negatively affect genetic diversity in wild relatives to a greater extent than ongoing gene flow fromnon-transgenic eggplant.Risks to Biological DiversityConclusion 6. Most of the main kinds of possible adverse effects of Bt brinjal on biological species diversityand ecosystems have not been evaluated sufficiently. The scientific evidence does not support the EC-II conclusion (page 42), Bt brinjal event EE-1 “has no adverse impact on non-target organisms includingbeneficial organisms and soil microflora.”The main potential adverse effects of a Bt crop to other species are:(A) Increased secondary pests, either through direct enhancement or through the reduction of natural enemy controls or othermeans;(B) Reduction in soil quality or health, adversely affecting crop production in either the short or long term;(C) Reduced value of non-crop economic activities (such as honey production or wild food harvesting);(D) Reduced cultural value by affecting a cultural icon or a species of cultural significance (e.g., Monarch butterfly in the UnitedStates);(E) Increased conservation concern, such as an adverse effect on an endangered species;(F) Reduced environmental quality through an effect on an ecosystem service such as pollination;(G) Increased human disease via environmental change.For Bt brinjal, (G) is unlikely, so a good risk assessment will focus on (A) through (F), allocating the most effort to address themost important issues. The conclusion follows from the following scientific considerations.Finding 13. The over-reliance of the GEAC risk assessment on the specificity of the Cry1Ac protein (EC-II, page 37)is not scientifically justified, and the risk assessment is considerably more uncertain than presently indicated.The GEAC risk assessment bases its analysis of effects on other species on an assumption about the specificity of Cry1Ac,which is stated in EC-II (page 37) and the Dossier (volume 1, page 38) (detailed below). There are three critical weaknesses tothis specificity hypothesis that renders it a poor assumption on which to base the assessment.First, the EC-II assessment states: “… non-target insects lack receptors for the proteins on the surface of their gut cells.”The actual evidence that all non-target species lack receptors for Cry1Ac on the midgut epithelium is quite poor. Toxicity inarthropods is incompletely known, but present understanding involves interaction of the Cry toxins with at least two geneproducts produced by the organism. Genome sequencing work to date has shown that vertebrate lineages do not have any
Page 1 and 2: Table of Contents 1Bt Brinjal Event
Page 3 and 4: Table of Contents iBt Brinjal:The s
Page 5 and 6: Summary and Conclusion 1Summary an
Page 7 and 8: Summary and Conclusion 3The EE-1 t
Page 9 and 10: Summary and Conclusion 5Event EE-1
Page 11 and 12: Summary and Conclusion 7Conclusion
Page 13 and 14: Context and Need 9standards for ER
Page 15 and 16: Context and Need 11and seek to incr
Page 17 and 18: Context and Need 13the reported yie
Page 19 and 20: Characterisation of Transgene 15Cha
Page 21 and 22: Characterisation of Transgene 17wor
Page 23 and 24: Characterisation of Transgene 19In
Page 25 and 26: Characterisation of Transgene 21Sci
Page 27 and 28: Environmental Risk Assessment 23Gen
Page 29: Environmental Risk Assessment 25thi
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