1、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 b

2、enefits 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 safetyChapter 1 IntroductionWhat is biotechnology?Maybe not to

3、o 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 "biotech

4、nology" 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,

5、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

6、, 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 Stat

7、us 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 transge

8、nic 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-r

9、esistance,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 contr

10、ibutions to the world's 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 worl

11、dwide 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 con

12、troversial.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 h

13、as 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 simi

14、larities 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

15、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, p

16、roteomics, 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

17、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 avai

18、lable.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 ye

19、ars 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 b

20、asis 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) h

21、ave 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 furt

22、her 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 approp

23、riate 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

24、 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

25、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 phenoty

26、pic 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 potat

27、o. 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 funct

28、ion 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

29、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 organ

30、izing 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 safe

31、ty 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

32、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 h

33、armonization 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 g

34、enetically 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 ri

35、sk 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 safe

36、ty, 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 avail

37、able. 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

38、 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

39、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 particul

40、ar 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, analogo

41、us 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 stu

42、dy into account. The minimum requirement to demonstrate the safety of long-term consumption of a food is a sub chronic 90-day study. Longer-term studies may be needed if the results of a 90-day study indicate adverse effects such as proliferative changes in tissues.The Expert Consultation noted that

43、, in general, very little is known about the potential long-term effects of any foods, and that identification of such effects may be very difficult, if not impossible, due to the many confounding factors and the great genetic variability in food-related effects among the population. Thus the identi

44、fication of long-term effects specifically attributable to genetically modified foods is highly unlikely. Epidemiological studies are not likely to identify such effects given the high background of undesirable effects of conventional foods. The Consultation was of the opinion that pre-market safety

45、 assessment already gives an assurance that genetically modified foods are as safe as their conventional counterparts. Experimental studies, such as randomized controlled human trials, if properly performed, might provide additional evidence for human safety in the medium to long term.Chapter 4 Conc

46、lusionFrom the above,we can clearly see that since the GM food isn't exactly safe,but our country and some international organizations like FAO and WHO developed a sufficient number of rules and regulations to reduce the risk of accidents.and what's more,since now not any serious GM safety a

47、ccident has happened.so we can enjoy the benefits of the modern biotechnology.so much worries isn't needed,and we are also trying some new way which can avoid the accident.GM food is safe enough only if we follow the rules.and we can use the modern biotechnology.Reference1Pamela Peter：Pamela Pet

48、ers, 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轉基因食品安全問題摘要：眾所周知，現代生物技術給人類帶來了許多好處：通過生物技術的廣泛應用，在全球農業產品中，可以很容易的看到糧食生產的顯著增加。但是，當我們享受轉基因食品的巨大利益時，一個新的但令人

49、擔憂的問題也來了，如果這些食品對人類是否足夠安全？如果有一些嚴重的事情發生，我們能做些什么呢？也許你可以在這篇論文中找到一些答案。關鍵字：現代生物技術 轉基因食品安全第1章：簡介 生物技術是什么？也許不是太多的人知道它的定義。精確的生物技術是一種技術，它可以改革和通過利用在生命科學研究使自然生命的組成部分很大程度上遵循人類的意愿。其最純粹的形式，“生物技術”一詞是指通過生物體或其產品的使用，改善人類健康和人類生存環境。 生物技術自史前時代就在以一種形式或另一種形式蓬勃發展。當人類意識到，他們可以種植自己的糧食和培育自己的動物，他們就學會了使用生物技術。當他們發現果汁發酵成酒，牛奶變成奶酪或酸奶

50、，啤酒可以通過發酵麥芽糖和啤酒花制得的結論時，就開始了對生物技術的研究。當第一個面包師發現，他們可以制得松軟的面包，而不是一個堅硬的薄餅干，他們被作為初出茅廬的生物技術。第一個動物飼養員發現不同的身體特征可以通過動物之間適當的交配放大或消失，他就在從事生物技術的處理。 第2章：轉基因食品的現狀大家都知道，現代生物技術已經給人類帶來了巨大的好處：通過生物技術的應用，在全球農業生產中，食品生產大量而廣泛的增長可以容易的被看到。自從1983年人類第一次利用轉基因煙草，馬鈴薯重組DNA技術，轉基因植物的研究和開發，取得了一系列顯著的進展，并已成功培育抗病，抗藥性作物，甚至世界植物基因工程技術已取得快速

51、發展和令人難以置信的高產。在他們的幫助下，我們可以養活另外一百多萬人。據統計，到現在為止，不到16億人已經從轉基因產品中獲益。我們的祖國，中國已對生物技術做出了巨大的貢獻。必須提到的是BT棉花和袁隆平的雜交水稻。商業化轉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的糧食是轉基因產品，全世界有29個國家生長轉基因作物。具有最大耕作面積的三個國家是美國，巴西和阿根廷。關于轉基因產品的安全問題已經引起爭論。轉基因食品將會給人類和動物帶來未知的過敏和毒素。第3章：轉基因食品的安全問題 關于轉基因植物食品安全評

52、估的原則，國際上已達成共識。等價物的概念已經發展成安全評估框架的一部分，現存食物的合適副本可以充當與轉基因食品安全對比的一個基礎。應用的概念本身并不是一個安全評估，但有助于鑒定現有的產品與新產品的相似與不同。等價物是在安全性評價的起點，而不是一個評估的終點。這個原則的實際應用所達成的共識應該被更好的制作。新插入的蛋白質和整個轉基因食品的安全性被測試，并討論現代測試方法的局限性。新測試方法的發展和確認，像DNA芯片技術，蛋白質組學和新陳代謝學對鑒定和描述都產生意想不到的效果，這可能會做為基因修正的結果被介紹。對新插入標記基因的蛋白質的過敏性評估進行了討論。來自轉基因作物的食品上市后監測的問題，將

53、在不久的將來得到重視。想其它的一樣，它被總結為等價物原則的應用已充分證明，而且沒有其他足夠的安全評估策略可用。在引進現代植物育種生物技術和糧食生產系統重組DNA技術的早期階段，努力開始轉向對來自于轉基因生物體（GMOs）的安全問題，這有關定義國際的和諧評估戰略。1988年，首次在植物上（煙草）成功實驗后的兩年，國際食品生物技術局（IFBC）公布了對這些新品種安全性評估問題的首份報告（IFBC，1990年）。在本報告所述的比較研究的方法，為以后的安全性評價戰略奠定了基礎。其他組織，如經濟合作與發展組織（OECD），聯合國糧食，農業組織（FAO），世界衛生組織（WHO）和國際生命科學學會（ILSI

54、）組織，都已經為安全評估制定了進一步的指導方針，獲得食品安全評估專家的廣泛國際共識。在1993年，經濟合作與發展組織制定的等價概念作為重大指導工具來評估轉基因食品，這在隨后的幾年中得到了進一步的闡述（OECD，1993;經合組織，1996年，經合組織，1998年;圖1）。實質等同的概念是食品安全評估框架的一部分，這個評估框架是依據現存事物充當一個基礎來與其對應的轉基因產品作對照。現有的食品供應被認為是安全的，因為經歷了很長的使用歷史，盡管它是公認可能含有多種抗營養物質和有毒物質的食品，在一定的消耗量下，可能會對人類和動物產生有害的影響。應用的概念本身并不是一個安全評估，但有助于確定現有的食品和新產品之間的相似有不同，并作進一步的毒理學來調查。設想三種情景中的轉基因植物或食物：（i）等價物;（ii）除了插入特征的等價物;（iii）沒有等價物。成分分析的關鍵部件，包括主要營養成分和天然毒物，是實質等同評估的基礎，除了轉基因植物的性狀和農業特征。在第一種情況下，沒有對產品做進一步特定測試的要求，因為該產品已具有與其對應傳統產品的特征，他們的消費被認為是安全的，例如，馬鈴薯淀粉的特點。在第二種情況下，除了插入的特性，該等價物將合適，所以安全檢測的重點是這個插入的特征，例如，具有殺蟲蛋白的轉基因