生物论文(英汉互译).doc

专业英语课程论文 题 目 转基因食品的安全问题学生姓名 学 号 专 业 指导教师 教学单位 二零一二年 六 月 十 八 日转基因食品的安全问题闫志铎(德州学院物理系，山东德州253023)摘要： 众所周知，现代生物技术给人类带来了许多好处：通过生物技术的广泛应用，在全球农业产品中，可以很容易的看到粮食生产的显著增加。但是，当我们享受转基因食品的巨大利益时，一个新的但令人担忧的问题也来了，如果这些食品对人类是否足够安全？如果有一些严重的事情发生，我们能做些什么呢？也许你可以在这篇论文中找到一些答案。关键字：现代生物技术 转基因食品安全目录英文摘要1第1章：简介1第2章：转基因食品的现状2第3章：转基因食品的安全问题2第四章：结论5参考文献5第1章：简介 生物技术是什么？也许不是太多的人知道它的定义。精确的生物技术是一种技术，它可以改革和通过利用在生命科学研究使自然生命的组成部分很大程度上遵循人类的意愿。其最纯粹的形式，“生物技术”一词是指通过生物体或其产品的使用，改善人类健康和人类生存环境。 生物技术自史前时代就在以一种形式或另一种形式蓬勃发展。当人类意识到，他们可以种植自己的粮食和培育自己的动物，他们就学会了使用生物技术。当他们发现果汁发酵成酒，牛奶变成奶酪或酸奶，啤酒可以通过发酵麦芽糖和啤酒花制得的结论时，就开始了对生物技术的研究。当第一个面包师发现，他们可以制得松软的面包，而不是一个坚硬的薄饼干，他们被作为初出茅庐的生物技术。第一个动物饲养员发现不同的身体特征可以通过动物之间适当的交配放大或消失，他就在从事生物技术的处理。 第2章：转基因食品的现状大家都知道，现代生物技术已经给人类带来了巨大的好处：通过生物技术的应用，在全球农业生产中，食品生产大量而广泛的增长可以容易的被看到。自从1983年人类第一次利用转基因烟草，马铃薯重组DNA技术，转基因植物的研究和开发，取得了一系列显着的进展，并已成功培育抗病，抗药性作物，甚至世界植物基因工程技术已取得快速发展和令人难以置信的高产。在他们的帮助下，我们可以养活另外一百多万人。据统计，到现在为止，不到16亿人已经从转基因产品中获益。我们的祖国，中国已对生物技术做出了巨大的贡献。必须提到的是BT棉花和袁隆平的杂交水稻。商业化转基因水稻可以追溯到1996年，包括大豆，棉花，谷物和油籽，油菜作物占全球耕地的10。在2010年，全球81%的大豆，64的棉花，29和23的粮食是转基因产品，全世界有29个国家生长转基因作物。具有最大耕作面积的三个国家是美国，巴西和阿根廷。关于转基因产品的安全问题已经引起争论。转基因食品将会给人类和动物带来未知的过敏和毒素。第3章：转基因食品的安全问题 关于转基因植物食品安全评估的原则，国际上已达成共识。等价物的概念已经发展成安全评估框架的一部分，现存食物的合适副本可以充当与转基因食品安全对比的一个基础。应用的概念本身并不是一个安全评估，但有助于鉴定现有的产品与新产品的相似与不同。等价物是在安全性评价的起点，而不是一个评估的终点。这个原则的实际应用所达成的共识应该被更好的制作。新插入的蛋白质和整个转基因食品的安全性被测试，并讨论现代测试方法的局限性。新测试方法的发展和确认，像DNA芯片技术，蛋白质组学和新陈代谢学对鉴定和描述都产生意想不到的效果，这可能会做为基因修正的结果被介绍。对新插入标记基因的蛋白质的过敏性评估进行了讨论。来自转基因作物的食品上市后监测的问题，将在不久的将来得到重视。想其它的一样，它被总结为等价物原则的应用已充分证明，而且没有其他足够的安全评估策略可用。在引进现代植物育种生物技术和粮食生产系统重组DNA技术的早期阶段，努力开始转向对来自于转基因生物体（GMOs）的安全问题，这有关定义国际的和谐评估战略。1988年，首次在植物上（烟草）成功实验后的两年，国际食品生物技术局（IFBC）公布了对这些新品种安全性评估问题的首份报告（IFBC，1990年）。在本报告所述的比较研究的方法，为以后的安全性评价战略奠定了基础。其他组织，如经济合作与发展组织（OECD），联合国粮食，农业组织（FAO），世界卫生组织（WHO）和国际生命科学学会（ILSI）组织，都已经为安全评估制定了进一步的指导方针，获得食品安全评估专家的广泛国际共识。在1993年，经济合作与发展组织制定的等价概念作为重大指导工具来评估转基因食品，这在随后的几年中得到了进一步的阐述（OECD，1993;经合组织，1996年，经合组织，1998年;图1）。实质等同的概念是食品安全评估框架的一部分，这个评估框架是依据现存事物充当一个基础来与其对应的转基因产品作对照。现有的食品供应被认为是安全的，因为经历了很长的使用历史，尽管它是公认可能含有多种抗营养物质和有毒物质的食品，在一定的消耗量下，可能会对人类和动物产生有害的影响。应用的概念本身并不是一个安全评估，但有助于确定现有的食品和新产品之间的相似有不同，并作进一步的毒理学来调查。设想三种情景中的转基因植物或食物：（i）等价物;（ii）除了插入特征的等价物;（iii）没有等价物。成分分析的关键部件，包括主要营养成分和天然毒物，是实质等同评估的基础，除了转基因植物的性状和农业特征。在第一种情况下，没有对产品做进一步特定测试的要求，因为该产品已具有与其对应传统产品的特征，他们的消费被认为是安全的，例如，马铃薯淀粉的特点。在第二种情况下，除了插入的特性，该等价物将合适，所以安全检测的重点是这个插入的特征，例如，具有杀虫蛋白的转基因番茄。安全测试，包括具体的毒性测试，这个测试根据新表达蛋白的性质和功能进行，有可能发生意想不到的效果，转基因食品的基因可能转移到人类/动物肠道菌群中;这是新插入性状的潜在变性原理和在饮食上中新食物的作用。在第三种情况下，新作物或食品将不会很大程度上与一个传统等价物对应，并根据新产品的特点，开展了一个新食品的个例评估。自1990年以来，粮农组织（粮食和农业组织的简称）和WHO（世界卫生组织）已经为现代转基因生物的安全建立讲习班和磋商。在1996年，联合粮农组织/世卫组织（粮农组织/世卫组织，1996年）提供咨询。有人建议，安全性评价应基于等价物的概念，这是一个动态的，分析和现有食物相关的新食物的安全。应考虑以下参数，以确定实质等同的转基因植物，分子特征，表型特征，主要营养，毒物和过敏原。三个水平等价物（完全，部分，没有）与其相对应新食物之间的区别，以及与大量等价物作进一步测试的决定，都与经济合作发展组织所定义的相似（1996）。联合国粮食与农业组织/世界卫生组织的食品法典委员会致力于国际食物标准的融洽。通过食品法典委员会制定的食品标准应当被各国政府采纳。生物技术食品法典特设政府有任务发展转基因食品的标准，指导方针和其他建议。2000年3月，在千叶（日本）的第一届会议上，关于转基因食品的“风险评估”和“风险分析”定义被同意。风险评估包括诸如食品安全，大量的等效性和长期的健康影响，而风险分析可能包括决策和上市后监测等问题。自从1996年的磋商会后，2000年五月/六月在瑞士日内瓦举行专家磋商会来聚集评价经验。审议的议题包括实质等同性，基因改造，食品安全，营养的影响，抗生素抗性标记基因和过敏源。对转基因食品的安全性评估，研讨会赞同等价物作为一个有效的方法，并得出结论，目前没有合适可利用的替代策略。概念的应用是一个安全评估的起点，而不是一个终点。鉴别转基因食物与它合适的对应物之间的相似和可能不同，这应该作进一步的评估对由于基因改造过程中而发生的潜在不确定效应的问题，进行了检查，如现有性状的缺失或增加一个新的性状。这种不确定效应并不只是针对DNA复制技术，在传统育种方面也经常发生。检测这种效应的现有方法集中于对已知营养物和毒物的化学分析（定向方法）。为了提高检测这种不确定效果的可能性，分析/辨别方法被认为是有用的方案（非定向办法）。当在不确定效果的发生率增加时，基因的大量修改对于植物非常有利（第二代转基因食品）。动物研究认为有必要获取新表达蛋白质的特征，类似于传统的食品添加剂的毒性试验。整个食品的测试可能会考虑，除了期望的以外，合成物的相关变化也可能发生；然而，这些研究应该在个例的基础上被考虑，把这种研究的局限性考虑进去。证明长期消费食品安全的最低要求是对慢性毒性90天的研究。如果一个90天的研究结果表明出现诸如组织增生的不良反应，可能还需要更长期的研究。专家磋商会指出，在一般情况下，所有食物的长期潜在影响很少被知道，并且鉴别这种效果可能非常困难，是由于许多混杂因素和巨大的遗传变异存在与食物有关的效果。因此，鉴别长期的影响，特别是由于转基因食品引起的影响是极不可能的。流行病学研究不容易识别这种在高背景下传统食品的不良影响。研讨会认为，市场前的安全评估已经给出了一个保证，转基因食品和其对应传统等价物一样安全。如随机控制人体特征的试验研究，如果正确执行，为人类的安全，可能在中长期提供更多的证据。第4章：结论从上面，我们可以清楚地看到，因为转基因食品并不是完全安全的，但我们的国家和一些国际组织如联合国粮农组织和世界卫生组织制定了足够数量的规章制度，以减少风险，更何况，现在没有任何严重的转基因安全事故发生。我们可以没有那么多顾虑来享受转基因技术的好处。，我们也尝试了一些能避免事故的新方式。只要我们遵循规则和我们可以利用的现代生物技术，转基因食品是足够安全参考文献1Pamela Peter：Pamela Peters, from Biotechnology: A Guide To Genetic Engineering. Wm. C. Brown Publishers, Inc., 1993.2Fred Gould:Can Agricultural Biotechnology be Green? 3Norman Borlaug:Biotechnology and the Green Revolution Genetically modified food safety issuesAbstractAs we all know,modern biotechnology has brought human numerous benefits:Through the application of biotechnology, a broad and significant increase of food production can be happily seen at global agricultural production. But when we enjoy the enormous benefits of the GM food,a new but alarming problem also came that if these food is safe enough for people?if something seriously happened,what can we do?Maybe you can find some answer in this thesis.Key Words: modern biotechnology GM food safetyContentsabstract in English1chapter 1 introduction.1chapter 2 Status of genetically modified foods2Chapter 3 GM food safety issues2Chapter 4 Conclusion7Reference7Chapter 1 IntroductionWhat is biotechnology?Maybe not too mang people know its definition accurately.Biotechnology is a technology which can reform and make the use of the natural lives on the ingredient of them by taking advantage of the research finds in life sciences which can greatly follow the will of people.In its purest form,the term biotechnology refers to the use of living organisms or their products to modify human health and the human environment. Biotechnology in one form or another has flourished since prehistoric times. When the first human beings realized that they could plant their own crops and breed their own animals, they learned to use biotechnology. The discovery that fruit juices fermented into wine, or that milk could be converted into cheese or yogurt, or that beer could be made by fermenting solutions of malt and hops began the study of biotechnology. When the first bakers found that they could make a soft, spongy bread rather than a firm, thin cracker, they were acting as fledgling biotechnologists. The first animal breeders, realizing that different physical traits could be either magnified or lost by mating appropriate pairs of animals, engaged in the manipulations of biotechnology. Chapter 2 Status of genetically modified foodsAs we all know,modern biotechnology has brought human numerous benifits:Through the application of biotechnology, a broad and significant increase of food production can be happily seen at global agricultural production.Since 1983 when the first time human got transgenic tobacco, potato by using recombinant DNA technology,the plant genetic engineering technology in the world has achieved rapid development of transgenic plants for research and development,which has made a series of remarkable progress and has Successfully nurtured a number of crops with disease-resistance,insecticide resistance and even an incredible high-yield.with the help of them,we can feed another more than millions of people,According to statistics,up to now ,no less than 1.6 billion people have benefits from biotechnology.in the area,our mother country China has made tremendous contributions to the worlds biotechnology.what must be mentioned is BT cotton and hybrid rice of Yuan Longping. Commercialize genetically modified crops dates from the year of 1996,including Soybeans, cotton, cereals and oilseed rape.GM crops now occupy 10% of global arable land. In 2010,81% of worldwide soybean, 64% cotton, 29% and 23% of the grain is genetically modified oilseed rape.Totally,29 countries grow GM products all over the world.the top three country with the largest area of cultivation is United States, Brazil and Argentina.The problem About the safety of GM products has been controversial.Genetically modified food will bring human and animal allergens and toxins of unknown.Chapter 3 GM food safety issues International consensus has been reached on the principles regarding evaluation of the food safety of genetically modified plants. The concept of substantial equivalence has been developed as part of a safety evaluation framework, based on the idea that existing foods can serve as a basis for comparing the properties of genetically modified foods with the appropriate counterpart. Application of the concept is not a safety assessment per se, but helps to identify similarities and differences between the existing food and the new product, which are then subject to further toxicological investigation. Substantial equivalence is a starting point in the safety evaluation, rather than an endpoint of the assessment. Consensus on practical application of the principle should be further elaborated. Experiences with the safety testing of newly inserted proteins and of whole genetically modified foods are reviewed, and limitations of current test methodologies are discussed. The development and validation of new profiling methods such as DNA microarray technology, proteomics, and metabolomics for the identification and characterization of unintended effects, which may occur as a result of the genetic modification, is recommended. The assessment of the allergenicity of newly inserted proteins and of marker genes is discussed. An issue that will gain importance in the near future is that of post-marketing surveillance of the foods derived from genetically modified crops. It is concluded, among others that, that application of the principle of substantial equivalence has proven adequate, and that no alternative adequate safety assessment strategies are available.At an early stage in the introduction of recombinant-DNA technology in modern plant breeding and biotechnological food production systems, efforts began to define internationally harmonized evaluation strategies for the safety of foods derived from genetically modified organisms (GMOs). Two years after the first successful transformation experiment in plants (tobacco) in 1988, the International Food Biotechnology Council (IFBC) published the first report on the issue of safety assessment of these new varieties (IFBC, 1990). The comparative approach described in this report has laid the basis for later safety evaluation strategies. Other organizations, such as the Organisation for Economic Cooperation and Development (OECD), the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) and the International Life Sciences Institute (ILSI) have developed further guidelines for safety assessment which have obtained broad international consensus among experts on food safety evaluation.At 1993. the OECD formulated the concept of substantial equivalence as a guiding tool for the assessment of genetically modified foods, which has been further elaborated in the following years (OECD, 1993; OECD, 1996; OECD, 1998; Figure 1). The concept of substantial equivalence is part of a safety evaluation framework based on the idea that existing foods can serve as a basis for comparing the properties of a genetically modified food with the appropriate counterpart. The existing food supply is considered to be safe, as experienced by a long history of use, although it is recognized that foods may contain many anti-nutrients and toxicants which, at certain levels of consumption, may induce deleterious effects in humans and animals. Application of the concept is not a safety assessment per se, but helps to identify similarities and potential differences between the existing food and the new product, which is then subject to further toxicological investigation. Three scenarios are envisioned in which the genetically modified plant or food would be (i) substantially equivalent; (ii) substantially equivalent except for the inserted trait; or (iii) not equivalent at all. A compositional analysis of key components, including key nutrients and natural toxicants, is the basis of assessment of substantial equivalence, in addition to phenotypic and agronomic characteristics of the genetically modified plant.In the first scenario, no further specific testing is required as the product has been characterized as substantially equivalent to a traditional counterpart whose consumption is considered to be safe, for example, starch from potato. In the second scenario, substantial equivalence would apply except for the inserted trait, and so the focus of the safety testing is on this trait, for example, an insecticidal protein of genetically modified tomato. Safety tests include specific toxicity testing according to the nature and function of the newly expressed protein; potential occurence of unintended effects; potential for gene transfer from genetically modified foods to human/animal gut flora; the potential allergenicity of the newly inserted traits; and the role of the new food in the diet . In the third scenario, the novel crop or food would be not substantially equivalent with a traditional counterpart, and a case-by-case assessment of the new food must be carried out according to the characteristics of the new product.FAO（short for Food and Agriculture Organization） and WHO(World Health Organization) have been organizing workshops and consultations on the safety of GMOs since 1990. At the Joint FAO/WHO Consultation in 1996 (FAO/WHO, 1996) it was recommended that the safety evaluation should be based on the concept of substantial equivalence, which is a dynamic, analytical exercise in the assessment of the safety of a new food relative to an existing food. The following parameters should be considered to determine the substantial equivalence of a genetically modified plant: molecular characterization; phenotypic characteristics; key nutrients; toxicants; and allergens.The distinction between three levels of substantial equivalence (complete, partial, non-) of the novel food to its counterpart, and the subsequent decisions for further testing based upon substantial equivalence, are similar to those defined by OECD (1996).The Codex Alimentarius Commission of FAO/WHO is committed to the international harmonization of food standards. Food standards developed by Codex Alimentarius should be adopted by the participating national governments. The Codex ad hoc Intergovern mental Task Force on Foods Derived from Biotechnology has the task to develop standards, guidelines and other recommendations for genetically modified foods. During its first session in Chiba (Japan) in March 2000 definitions were agreed concerning the risk assessment and risk analysis of genetically modified foods. Risk assessment covers issues such as food safety, substantial equivalence and long-term health effects, while risk analysis may include decision-making and post-market monitoring.An Expert Consultation held in Geneva, Switzerland in May/June 2000 evaluated experiences gathered since the 1996 Consultation. Topics considered included substantial equivalence, unintended effects of genetic modification, food safety, nutritional effects, antibiotic resistance marker genes, and allergenicity. The Consultation endorsed the concept of substantial equivalence as a pragmatic approach for the safety assessment of genetically modified foods, and concluded that at present no suitable alternative strategies are available. Application of the concept is a starting point for safety assessment, rather than an end-point. It identifies similarities and possible differences between the genetically modified food and its appropriate counterpart, which should then be assessed further.The issue of the potential occurrence of unintended effects due to the genetic modification process, such as the loss of existing traits or the acquisition of new ones, was examined. The occurrence of unintended effects is not unique for the application of recDNA techniques, but also occurs frequently in conventional breeding. Present approaches to detecting such effects focus on chemical analysis of known nutrients and toxicants (targeted approach). In order to increase the possibility of detecting unintended effects, profiling/fingerprinting methods are considered useful alternatives (non-targeted approach). This is of particular interest for plants with extensive modifications of the genome (second generation of genetically modified foods) where chances of the occurrence of unintended effects may increase.Animal studies are deemed necessary to obtain information on the characteristics of newly expressed proteins, analogous to the conventional toxicity testing of food additives. Testing of whole foods may be considered if relevant changes in composition may have taken place in addition to the expected ones; however, such studies should be considered on a case-by-case basis, taking the limitations of this type of study into account. The minimum requirement to demonstrate the safety of long-term consumption of a food is a sub chronic 90-day study.