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Online Journal - URL: http://bioline.bdt.org.br/by Biotechnology, Biosafety and Impact Assessment: Field Trials of Transgenic Crops in Developing Countries Andre de Kathen
Dept of Molecular Genetics, University of Hannover, Herrenhauserstr. 2,
30419 Hannover, Germany
Received April 10th, 1997
Code Number: BY97004
Size of Files:
Text: 37K
No associated graphics filesABSTRACT The deliberate release of transgenic crops is often taken to be an indicator of agricultural biotechnology development. However, less than 10% of the field trials world wide have been carried out in Developing Countries (DCs) and it seems that more than 80% of these were carried out by multinational companies to speed up seed production in the counter season or to test transgenic crops under special environmental conditions. The DCs differ widely in their legal, religious, political and social system as well as in issues such as educational standards, agronomic tradition and national income. Generally, these countries have not evolved an appropriate biotechnology market structure, hindering the development of an "indigenous" biotechnology capacity, a prerequisite for establishing and translating Biosafety Guidelines within a legally binding system. Several countries in the developing world, although highly interested in establishing agrobiotechnology capacities, have neither developed a national or regional programme nor guidelines for the safe use of modern biotechnology tools. An overview on the actual situation is given. The release of transgenic plants in DCs is, despite its implications for trade agreements, intellectual property rights and a Biosafety Protocol, of particular interest for impact assessment studies, because most of the worlds biodiversity is located there. It appears that the potential impact or risk assessment discussion in DCs, if it is actually carried out, is based on scientific assumptions and clearly balances risks and benefits. It is also clear that the information needed to predict the impact in a particular case is not, and probably will not be, available. General strategies for risk and benefit assessment have been discussed in several workshops and meetings in DCs and clearly show that the potential benefits outweigh the potential ecological risks. Keywords: Agriculture, biotechnology, biosafety, developing countries, transgenic crops, field release, impact assessment, research INTRODUCTION The first transgenic plants were generated only 13 years ago (De Block et al., 1984 Horsch et al., 1984, ). Since than, transgenic crops have been released on more than 15,000 sites worldwide [3]. According to the USDA, in the USA more than 2.500 permits and notifications allowed field trials on more than 10.000 sites. Actual information can be obtained from received from the APHIS web site : http://www.aphis.usda.gov/bbep/bp/database.html. On a global scale, more than 50 different plant species have been genetically engineered and deliberately released in about 35 different countries. The projected value of transgenic plants is estimated to reach about 2-3 billion US$ in the year 2000 and will double by 2005. Field releases in DCs account for less than 10% of the total and have been mainly carried out by transnational companies, usually for the purpose of accelerating seed production in the counter season. Several reasons account for the limited number of field releases of transgenic crops in DCs:
- lack of infrastructure and private initiative; - lack of adapted biosafety guidelines (a prerequisite for technology transfer); - uncertainties in analysing or predicting potential ecological and socioeconomic impacts.
It should be realized, although this is out of the focus of the present contribution, that the set-up of demand-driven research, the establishment of appropriate biotechnology capacities and the development of private market structures and distributing systems are of prime importance; without this Biosafety is not a topic at all. Effort and public investment has to increase significantly if the promises made are taken seriously. BIOSAFETY AND BIOSAFETY GUIDELINES The development of biosafety regulations in DCs appears to be important for three different reasons:
- GMOs developed by companies or in international research projects will not be tested in countries with no biosafety regulations, and - the transfer of modern biotechnology methods requires the adoption of biosafety guidelines. Potential donors will refuse to invest into the establishment of modern biotech-capacities, if biosafety issues are not clarified.
Questions which arise for Biosafety Guidelines include: Should they be established as:
- do they require a specific legislation and administration, and - should they be specific for recombinant products or general, i.e. process or product based.
The pattern of development of Biosafety Guidelines in DCs is diverse. However, in most cases there is the tendency to develop technical guidelines and central, so-called, National Biosafety Committees. However, the formulation of relevant legislation is delayed in many countries. Numerous international and national organisations are involved in assisting DCs in developing guidelines and legislation including the European Community, OECD, CGIAR, WHO, FAO, UNEP, UNIDO, USAID, GTZ, SEI/BAC, IUCN, Greenpeace and many more. About 20 international workshops have addressed the problem as well and guidelines and codes of conduct have been produced to a large extent. A question overhangs the extent to which efforts have been coordinated - for example by the four different United Nations organisations which have been involved and one may ask if the number of workshops is proportional to the quality. Is it helpful -in the light of a international Biosafety Protocol- to develop more guidelines and does this contribute to a needed harmonization and does it preserve or protect the world's biological resources? Miller (1996) states "Quite the contrary, the kind of regulation being contemplated, which would cover, for example, field trials of improved varieties of potatoes, maize, rice, or cassava -plant varieties, that are neither unknown nor dangerous- would discourage innovative research and development and commit the participating nations to a kind of highest common denominator level of regulation". The proceedings of recent workshop organized by the Biotechnology Advisory Commission and the Stockholm Environment Institute give an excellent insight into respective problems, perspectives and the development of sound criteria (Miller, 1996). The following tables provide an overview on the current status of Biosafety Regulations in DCs. Data have been included to the end of 1995 and have been provided by the BAC/SEI, by the appropriate government representatives and the Biosafety Expert Group of the Convention of Biological Diversity (CBD). The actual situation has probably not changed dramatically in the last year. Only countries have been included for which field trials information has been reported from more then one source. Table 1: Development of biosafety guidelines in developing countries (1995)
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Biosafety Guidelines Biosafety Guidelines No
approved developed or Biosafety Guidelines
under development
---------------------------------------------------------------------------
Argentina Brazil Belize
Chile Bolivia Dominican Republic
Costa Rica Cuba Morocco
Egypt Columbia Paraguay
India Guatemala Uruguay
Mexico Indonesia Venezuela
Nigeria Kenya
Pakistan Malaysia
Peru Zimbabwe
Thailand
The Philippines
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It is striking, that up to now only a limited number of parties which have signed the Convention of Biological Diversity have established a regulatory framework on Biosafety. In addition, for many countries it is difficult to define to what extent the Convention is really functioning.
Table 2: State-of-development of biosafety regulations and responsible institutions
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Country Biosafety Regulation Responsible Organisation
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Argentina* technical guidelines Advisory Committee of Agricult.
Biotechn., CONABIA
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Belize -.- -.-
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Bolivia legislation under National Biosafety Committee
development
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Brazil legislation since 1995, National Biosafety Committee
technical guidelines under development
under development
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Chile technical guidelines, National Biosafety Committee
legislation in preparation
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Columbia technical guidelines -.-
under development
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Costa Rica technical guidelines, National Biosafety Committee
legislation in preparation
---------------------------------------------------------------------------
Cuba* technical guidelines, Centre for Genetic Engineering
legislation to be adopted and Biotechnology, CIGB
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Dominican -.- -.-
Republic
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Egypt technical guidelines per National Biosafety Committee
ministers decree
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Guatemala technical guidelines in National Biosafety Committee
preparation CONBIOTEC
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India since 1990 technical Genetic Engineering Approval
guidelines in place Committee (commercial)
Review Committee on Genetic
Manipulation (research)
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Indonesia under development probably via CFRIC, Central
Research Institute for Food Crops
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Kenya technical guidelines KARI Biosafety Committee
under development
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Malaysia technical guidelines National Working Group on
in preparation Biotechnology
---------------------------------------------------------------------------
Mexico technical guidelines National Committee: Direccion
General de Sanidad Vegetal
---------------------------------------------------------------------------
Nigeria technical guidelines National Biosafety Committee
under development; IBC-IITA
---------------------------------------------------------------------------
Pakistan technical guidelines -.-
---------------------------------------------------------------------------
Peru technical guidelines National Biosafety Committee
in preparation under development; IBC-CIP
---------------------------------------------------------------------------
The technical guidelines National Committee on Biosafety
Philippines* of The Philippines
---------------------------------------------------------------------------
Puerto Rico technical guidelines USDA - APHIS
according to USDA
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Republic of Biosafety Regulations based SAGENE
South Africa on existing legislation (to be reorganized)*
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Thailand * technical guidelines National Biosafety Committee
(Secretariat: NCGEB)
---------------------------------------------------------------------------
Venezuela -.- -.-
---------------------------------------------------------------------------
Zimbabwe technical guidelines Biotechnology Safety Board
to be approved to be established
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* Hypertext links are: Argentina; Cuba; Philipinnes; Thailand A SURVEY ON FIELD RELEASES OF TRANSGENIC CROPS IN DEVELOPING COUNTRIES A central database on field releases in DCs is not yet available and, therefore, published information may not be consistent, depending on the source. It is sometimes not clear what can be regarded as an individual field trial. In the following table, the confirmed releases cover those confirmed at least by two independent but responsible sources, describing a trial as a release of a crop species genetically engineered with one particular construct, in one year, regardless on how many sites. Table 3: Field releases in developing countries (including the 1994/1995 season) - excluding China, according to Virgin and Frederick, 1996. ISAAA-data are excerpted from James and Krattiger, 1996, including the 1995/96 season.
--------------------------------------------------------------------------- Countries surveyed Confirmed Releases* Total Releases ISAAA --------------------------------------------------------------------------- Argentina 43 43 78 Belize - 4 5 Bolivia 1 5 6 Brazil** - - - Chile 9 17 39 Costa Rica 6 8 17 Cuba 13 13 18 Dominican Republic 1 1 - Egypt 1 1 2 Guatemala 2 3 3 India 2 3 - Marocco 1 1 - Mexico 20 20 38 Peru 2 2 - Puerto Rico*** 21 (permits) 21 (permits) n.d. Republic South Africa 17 17 22 Thailand 1 1 2 TOTAL 140 160 231 ---------------------------------------------------------------------------
* "Confirmed Releases" were confirmed either by government sources or
private companies. "Total Releases" include also those, for which
confirmation from government/responsible company was not available. Whereas most of the countries, especially in the Latin Americas and the Caribbean, have been used for trials by US transnational companies, a limited number has carried out field trials according to their specific needs. For example, none of the field releases in Cuba concern herbicide resistance but some do concern resistance to fungal and viral diseases or insect pests.
Table 4: Releases of transgenic crops in developing countries, breakdown by species, based on De Kathen, (1996) and including (in brackets) data raised by ISAAA James and Krattiger, 1996
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Species Field releases herbicide- insect- virus- product-
resistance resistance resistance quality
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Maize 46 (68) 28 18 - -
Soybean 26 (36) 23 - 1 1
Cotton 24 (44) 14 16 - -
Tomato 20 (33) - 3 16 1
Potato 10 (14) - - 7 1
"others" 34 (n.d.) n.d. n.d. n.d. n.d.
TOTAL 160 65 (112) 37 (80) 24 (63) 3 (n.d.)
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The data documented in table 4 clearly demonstrate, that the agricultural production of Africa will not profit from modern biotechnology in the next decade, simply because staple food crops like taro, cassava, sweet potato, banana or sorghum/millet have not been in the focus of agrobiotechnology development. However, Sub-Sahara Africa urgently needs to improve their agricultural productivity in root - and tuber crops. Reflecting the investment for agrobiotechnology, the picture revealed by table 5 is not surprising and confirms the statements made above, i.e. that public investment in DCs has to support also the development of a private sector to strengthen demand-driven and sustainable developments. Table 5: Companies responsible for the deliberate release of transgenic crops in developing countries
--------------------------------------------------------------------------- Monsanto Calgene Asgrow Pioneer Ciba-Geigy AgrEvo others DCC* --------------------------------------------------------------------------- 27 24 16 10 8 6 8 40 (19.4) (17.3) (11.5) (7.2) (5.8) (4.3) (5.8) (28.8) --------------------------------------------------------------------------- total: 139 releases, percentage in brackets * DCC means developing country companies, although partnership by transnational companies not clear
RISK ASSESSMENT This section will focus on the potential ecological impact of the release of transgenic crops in Centres of Biodiversity. Other more intangible problems, for example socioeconomic issues, will not be discussed. From the ethical point of view - i.e. from a methodology describing or formulating the justification for doing "something"- genetic engineering or transgenic crops are not an issue as long as a serious debate on the value of "nature" and "biodiversity" is missing as well as an agreement on strategies to measure them. Nature and biodiversity are not only important for an ethical discussion. If it is stated that the release of transgenic crops may endanger nature or biodiversity, it is necessary to decide first if nature and biodiversity are regarded as a value which should be protected. In numerous cases - such as the construction of highways or clearing forests for agriculture- we have decided against nature. Of course, biodiversity may influence the stability of a particular ecosystem. But obviously it is not apparently clear to everybody a) if this particular ecosystem has to be protected (how and against what ?) and b) what is biodiversity. From the science point of view, the potential risk or impact of genetically engineered organisms on ecosystems should not differ from conventional products, as formulated by the OECD in their "concept of familiarity", (OECD 1993). Consequently, some of the potential risks are related to the establishment of new weeds or pests, the production of toxic compounds and allergens. However, transgenic crops do have two obvious and specific characteristics:
- the introduced DNA-sequence finds itself in a disturbed genetic context. Although empirical evidence is lacking, this may result in unexpected side-effects. The observed subsequent silencing of an introduced gene in the transgenic progeny or the "position-effects" influencing the level of gene-expression may serve as examples.
Nevertheless, it is the trait or the acquired property itself and not the process or method of introduction, which interacts with the environment and, therefore, largely determines the potential ecological impact. The only problem is: how can a risk from the property or phenotype be deduced? Although precautions must be taken with any new development, speculative risks are difficult to address, since proving the non-existence of a unknown risk is a logical impossibility. In addition, any manipulation of an ecosystem - by traditional farming or by releasing transgenic crops - affects its stability and diversity. However, there are only a few, mostly theoretical, studies available which estimate the potential impact of the release of transgenic crops Sawahel, 1994; Andow, 1994; Raybould and Grey, 1994; Crawley, 1992). This is surprising, since an ecological impact is not only restricted to recombinant DNA or transgenic plants. In other words, from the ecological point of view it makes no difference if an indigenous population is displaced by transgenic or non-transgenic invasive weeds. Currently, there are three general scenarios, describing how - hypothetically - transgenic crops may influence the composition and stability of a natural ecosystem: 1. The transgenic plant itself becomes a weed and either: a) leaves the area under cultivation and displaces wild species; i.e. the crop "escapes", or b) stays within the cultivated area as a "volunteer". Problems arise in defining what is a "weed". 2. The introduced DNA is sexually transmitted into the wild population and may confer weediness if expressed in the fertile progeny of a hybrid arising from a cross between the crop and its compatible wild relative. That the recombinant DNA spreads into wild populations can be regarded as a probable event, specifically in centres of biodiversity. However, not only recombinant DNA is transferred, the statement holds true for any DNA-sequence of the crop's genome - and the direction is not fixed. It would counteract any breeding effort if genes from the wild would be introduced and maintained with high frequency in the crop genome. In addition, any detrimental effect resulting from a hybridization between the transgenic crop and its wild relative implies that the hybrid has a better fitness than its parents. The hybrid may invade the area, if the new property (e.g. a virus-resistance) confers resistance to an important biotic or abiotic selective pressure outside the area under cultivation. Usually, new properties relevant in agricultural areas are irrelevant to wild populations. However, assuming that the transgene confers a higher fitness, then spreading of this dominant and single trait into the wild population is faster compared to recessive or multigenic traits. On the other hand, natural recessive and multigenic traits might not be subject of immediate selection and may stay latent in a population. It is important to realise that natural traits conferring resistances against pests and pathogens are often poorly understood on a molecular level, so that the spread of "natural" resistance traits cannot be traced easily. Comparing the "resistance-gene flow" from engineered transgenic and natural non-transgenic crops to its wild relatives would require a more detailed knowledge of the basic processes underlying natural resistances. If a transgene decreases significantly the fitness of the hybrid, the transgenic variants are rapidly lost. It is unlikely, that this will result in a loss of biodiversity. Although crops and hybrids may establish outside the cultured area there is no example of a crop or an interfertile hybrid which has become invasive. 3. The transgene is transmitted asexually to species of other kingdoms, for example to bacteria, viruses, or animals and may cause damage. This so-called horizontal gene-transfer occurs in nature (in fact the horizontal gene-transfer organized by the bacterial plant pathogen Agrobacterium tumefaciens is a most successful tool in genetic engineering of plants). This poorly understood dynamic gene-flux between the species might represent a driving force of evolution. In this respect, the underestimated role of cryptic DNA, viroids or endophytic and soil-borne microorganisms should be considered. A point of discussion with regard to the spread of recombinant DNA is whether the transfer of antibiotic resistance genes from transgenic plants to human pathogens counteracts the efficiency of the relevant antibiotic in human medicine. The contribution of transgenic plants to this has not been analysed so far. Keeping in mind that the respective genes are generally isolated from, at least in part, promiscuous bacteria in the wild, the added risk from transgenic crops appears to be marginal; why should one expect that the DNA takes the detour via higher plants ? If the (transgenic) crop becomes a weed, an indigenous species may be lost. However, the diversity of species in an ecosystem does not sufficiently describe biodiversity. The genetic variability within a species allows the adaption to a changing environment and guarantees the survival of the species. Therefore, not only the number of planted crops, i.e. the size of the founder-population, but also the number of introduced genes may influence the potential weediness. The more genes introduced into the system, the higher the possibility that an ecological niche within the system is found which perfectly fits to the set of genes introduced. Using Potato and Maize as model plants in two recent workshops in Latin America, a specific consideration for risk analysis in centres of biodiversity was the assumption that the gene-flow occurs. Impact analysis has, therefore, to focus on the consequence - not on the probability - of such a gene-flow. The proposed strategy, therefore, is:
- a case-by-case analysis, focusing on the impact of the trait to be introduced.
The question remains: which concept of risk assessment allows a prediction in a specific case. Two models are commonly discussed, the "OECD-Concept of Familiarity" and the "Exotic Species Model" (OECD, 1993; Crawley, 1992). Despite the problem in understanding why a risk assessment is needed if it is stated that transgenic crops are a priori not different from non-transgenic relatives, a recent report by the Austrian Federal Environment Agency (Torgerson, 1996) summarizes that it is hardly possible to infer effects directly from the traits. In agriculture, certain practices have considerable, short-term effects, whereas the long-term impacts - including climatic variations- can hardly be predicted. The Exotic Species Model may provide statistical data but is not helpful in predicting the fate of a new, engineered variety. Therefore, it should be considered that the ecological impact of a given variety is mainly determined by the agricultural practice. For example, higher standing ability in wheat or pea would led to a decrease in fungicide application - if it is not counteracted by higher lodging tendency due to higher head or pod weight or more heads or pods per plant.
Experimental data from field trials of transgenic organisms have increased confidence regarding the unlikelihood of global calamities due to the introduction of a limited number of genes. Nevertheless, certain transgene gene/environment combinations (e.g. plants engineered with fitness-altering genes and capable of interbreeding with wild relatives) need proactive research to assess potential long-term impacts. A problem which is usually not addressed by risk assessment strategies is the potential risk of changing the microbial community in the rhizosphere and within the plant (endophytes) by the introduction of resistance genes against bacterial or fungal pathogens. This problem - again - is not restricted to transgenic crops and was not addressed so far, because only 1-10% of the microbial community could be characterized (Hugenholtz and Pace, 1996). Now, with the emerging modern molecular tools, monitoring is possible but requires substantial funding.
REFERENCES Andow, D.A., (1994). Community response to transgenic plant release: using mathematical theory to predict effects of transgenic plants. Molecular Ecology, 3: 65-70. Crawley, M.J., (1992). The comparative ecology of transgenic and conventional crops. In: Casper, R., and Landsmann, J. (eds.). Proceedings of the International Symposium on The Biosafety Results of Field Tests of Genetically Modified and Organisms, Goslar-Braunschweig: Biologische Bundesanstalt fur Land- und Forstwirtschaft. De Block, M., Herrera-Estrella, L., van Montagu, M., Schell, J. and Zambryski, P. 1984, EMBO Journal, 3: 1681-1689. De Kathen, A,. (1996). The impact of transgenic crop releases on biodiversity in developing countries. Biotechnology and Development Monitor, No. 28: 10-14. Frederick RJ, Virgin I, Lindarte E (1995) Environmental concerns with transgenic plants in centers of diversity: potato as a model. Stockholm, The Biotechnology Advisory Commission of the Stockholm Environmental Institute and the Inter-American Institute for Cooperation on Agriculture. Horsch, R.B., Fraley, R.T., Rogers, S.G., Sanders, P.R., LLoyd, A. and Hoffman, N., 1984. Science, 223, 496-498. Hugenholtz, P. and Pace, N.R., (1996). Identifying microbial diversity in the natural environment: a molecular phylogenetic approach. TIBTECH, 14: 190-198. James, C. and Krattiger, A.,F., (1996). Global Review of the field testing and commercialization of transgenic plants: 1986-1995 -The first decade of crop biotechnology. ISAAA-Briefs No. 1. Miller, H. I., (1996). Biotechnology and the UN: New challenges, new failures. Nature Biotechnology 14: 831-834. OECD, (1993). Traditional crop breeding practices: a historical review to serve as a baseline for assessing the role of modern biotechnology. OECD, Paris. Raybould, A.F. and Gray, A.J., (1994). Will hybrids of genetically modified crops invade natural communities? Trends in Ecology and Evolution, 9/3: 85-89. Sawahel, W.A., (1994). Transgenic plants: performance, release and containment. World J. of Microbiol. & Biotechnol., 10: 139-144. Torgersen, H., (1996). Ecological impacts of traditional crop plants - a basis for the assessment of transgenic plants. Umweltbundesamt Osterreich, ISBN 3-85457-283-2. Virgin, I., Frederick R.J., (1996) Biosafety Capacity Building: Evaluation Criteria Development. Stockholm, The Biotechnology Advisory Commission of the Stockholm Environment Institute. ACKNOWLEDGEMENT The author would like to express his gratitude to the numerous scientists and representatives of governments, private companies and NGO's for helpful discussions. Note: Data documented in this article are partly based on a recent study published in German by the German Federal Environment Agency (Umweltbundesamt, Andre de Kathen, Texte 15/96, ISSN 0772-186X, Berlin, 1996). Since the author is conducting the preparation of an updated report on Agrobiotechnology in Developing Countries, which will focus on technology transfer, biosafety and risk assessment related issues, any information, criticisms and comments or corrections to the data presented will be highly welcome. Copyright remains with the author
Published by Bioline Publications, UK
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