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Genetically Modified Foods
Transcript of Genetically Modified Foods
by 1996 each of these GM foods were allowed in the US But why are scientists changing the genes of plants that have been farmed since the beginning? Genetically engineered crops have benefits which include: longer shelf life
more heart healthy unsaturated fats higher yield of drug producing or bio-fuel producing plants
the ability to absorb toxins in the air and reduce pollution
are less likely to cause life threatening allergic reactions
can help prevent cancer and osteoporosis Let`s see what you know All plants contain genes Genetically modified plants don`t contain genes Plants can be modified to contain animal genes True or False? A tomato containing jellyfish genes would taste like seafood You could go to the food store after this class and buy genetically engineered foods I (you) have never eaten a genetically engineered food TRUE FALSE TRUE FALSE TRUE You most likely have... Let's find out 75% of processed food in the U.S. contains some genetically modified ingredient(s) crackers, breakfast cereals, cooking oils, and things containing soy and corn (like high fructose corn syrup!) all contain GM ingredients What do the people say? Most people who responded that GM foods are safe to eat have a college education... data taken from Huffington post survey of 1,000 US adults chosen from their online survey group at random from Feb 28-Mar 1 Across the survey group, party and demographic did not matter on this issue... 22% of people polled said they have heard a lot about GM crops. 48% have heard a little and 25% said they have heard NOTHING. When did this start? Farmers have been crossing genes since farming began. By selectively breeding their seeds and saving the seeds from good yields, they change their crop to what works best for them.
In 1875 a hybrid cereal was created by crossing wheat and rye.
Biologically engineering something does the same thing that selectively cross breeding does, but much quicker and with more precise results. The first in lab GM experiment was in 1986. The project created a herbicide resistant tobacco plant. GM foods were first allowed in China in 1992, and were first seen in the Us in 1994. Follow the money The value of bio-tech seed alone in 2011 was $13.2 billion The end product of maize, soybean, grain, and cotton brought in approximately $160 billion or more per year All plants, animals and bacteria have a genetic makeup that changes over time. GM plants contain virtually the same genes as before, except certain genes are added or enhanced to create the desired outcome. Certain genes in animals, like resistance to cold can be inserted into a plant`s DNA to protect or enhance it. When inserting a gene into a plant, it is a specific gene, usually one based on resistance or nutrition production. The "fishy taste" gene would not be inserted into a plant. Each year, more countries are devoting land to grow GM crops due to their higher yields and benefits. Land area devoted to GM crops over time Ethics of Genetically Modified Foods There are three things to consider when thinking about the ethics of GM foods: The rights of people in various countries to choose to adopt GM technology Harms vs benefits for consumers and the environment The pursuit of new technology and innovation with adequate regulation Using applied ethics, we can analyze the claims and conclusions of those who object to GM foods to determine if their argument is sound. An ethically justifiable conclusion has two types of claims: factual assertions and claims of how the world ought to be When deciding whether or not GM foods should be sold, it is the consumers who ultimately decide. However, we base our decisions on both our feelings and our understanding, which comes from the scientists developing the technology So does the final decision really belong to the scientists in the end? Scientists have a responsibility to both the data that is presented or produced, and to society to provide honest information. The government of each country, or its people, make the decisions for what is allowed in that country. Depending on these decisions and restrictions, GM foods could become more prominent. This decision decides the fate of GM food innovation and research. But we must be careful not to make an uninformed decision! Mark Lynas was a strong advocate against GM foods. He even led people to tear up GM crops in an act of civil disobedience.
However, in a speech he admitted that their arguments were not based in science but on ideology or aesthetics. After immersing himself in GM science, Lynas found that, "a careful reading of the scientific evidence revealed that his previous opposition was untenable." Cons Environment Genetically modified crops act like regular crops. For example, they are planted in fields, interact with organisms that feed on them, and produce pollen. However, this has been viewed as both beneficial and detrimental Good to know: Bacillus thuringiensis (Bt) is a common biological pesticide used to help crops grow, and produces the Cry toxin that may be extracted and used as a pesticide. Chemical Use One of the major environmental benefits from using GM crops is the reduction in the use of pesticides.
Insect-resistant Bt-expressing crops will reduce the number of pest insects feeding on these plants without the farmers having to apply as much insecticides. Study: Global Impact of Biotech Crops: Socio-Economic and Environmental Effects, 1996-2006 Graham Brookes and Peter Barfoot of PG Economics Ltd. Examined examined specific global economic impacts on greenhouse gas emissions for each country where GM crops have been grown from 1996 to 2006,and focus on the environmental impacts associated with changes in the amount of insecticides and herbicides applied to the GM crops used in the various countries.
Results: According to their analysis, GM technology reduced pesticide spraying by 286 million kg and has decreased the environmental impact associated with herbicides and insecticides use on crops by 15.4 %.
According to their website, PG Economics Ltd. are reliable and state they are “a specialist provider of advisory and consultancy services to agriculture and other natural resource-based industries. Our specific areas of specialization are plant biotechnology, agricultural production systems, agricultural markets and policy.” PROS Non-Target Organisms Health Environment One of the major uses of GM crops is in insect pest control though the expression of cry genes from Bacillus thuringiensis (Bt). There are concerns that the cry toxin could target predatory and other beneficial or harmless insects as well as the targeted pest insect. Any organism that lacks the appropriate receptors in its gut cannot be affected by Bt. Study: Impact of Bt corn pollen on monarch butterfly populations: A Risk Assessment. Authors: Mark K. Sears, Richard L. Hellmich, Diane E. Stanley-Horn, Karen S. Oberhauser, John M. Pleasants,Heather R. Mattila, Blair D. Siegfried, and Galen P. Dively A collaborative research effort by scientists in several states and in Canada has produced information to develop a formal risk assessment of the impact of Bt corn on monarch butterfly populations. Research was focused on the acute toxic effects of Bt corn pollen and the degree to which monarch larvae would be exposed to toxic amounts of Bt pollen on its host plant, the common milkweed found in and around cornfields. Researchers both analyzed the effects of Bt sprays and pollens deposited in both laboratory and external environments.
Result: Both laboratory and field studies show no acute toxic effects at any pollen density that would be encountered in the field. The 2-year study suggests that the impact of Bt corn pollen from current commercial hybrids on monarch butterfly populations is negligible.
The various authors were members of respectable universities and belonged to departments that would deem them specialized in this subject. Biodiversity There are concerns that the genetic diversity of various crops will decrease, due to the fact that the development of GM varieties will lead to less cultivars being used overall. There is also fear that they will indirectly affect the diversity of other organisms. Also, there are concerns that the widespread and increased use of GM crops designed to resist agrochemicals will cause damage to the environment and to biodiversity. Emergence of Secondary Pests Studies have documented surges in secondary pests (which are not affected by Bt toxins) within a few years of adoption of Bt cotton. It is suspected that once the primary pest is brought under control, secondary pests have a chance to emerge due to the lower pesticide applications in Bt cotton cultivars. Study: Benefits of Bt Cotton Counterbalanced by Secondary Pests? Perceptions of Ecological Change in China Authors: Jennifer H. Zhao, Peter Ho, Hossein Azadi “The research is based on a survey of 1,000 randomly selected farm households in five provinces in China. Apart from farmers’ perceptions of secondary pests, we also assessed their basic knowledge of Bt cotton and their perceptions of Bt cotton in terms of its strengths and shortcomings (e.g., effectiveness, productivity, price, and pesticide use) in comparison with non-transgenic cotton.”
Results: Evidence was found that farmers in China perceive a substantial increase in secondary pests after the introduction of Bt cotton. It also seemed that the reduction in pesticide used in Bt cotton cultivars is significantly lower than that reported in research elsewhere. This is consistent with the hypothesis suggested by recent studies that more pesticide sprayings are needed over time to control emerging secondary pests, such as aphids, spider mites, and lygus bugs.
Jennifer Zhao is a Scientific Researcher at the Department of Animal Sciences of Wageningen University. This article was published in Environmental Monitoring and Assessment and discusses “technical developments and data arising from environmental monitoring and assessment, principles in the design of monitoring systems, and the use of monitoring data in assessing the consequences of natural resource management and pollution risks.” Gene Flow Genes from genetically modified organisms have the ability to pass from one organism to another just like an endogenous gene. The process is known as outcrossing and can occur in any new open-pollinated crop variety. There are concerns that the spread of genes from modified organisms to unmodified relatives could produce species of weeds resistant to herbicides or could disrupt the ecosystem. Study: Evidence for the Establishment and Persistence of Genetically Modified Canola Populations in the U.S. Researchers confirmed casual observations of feral genetically modified canola populations in North Dakota, USA, by establishing transects along roads throughout the state. 406 samples were collected, tested for the presence of CP4 EPSPS protein (confers tolerance to glyphosate herbicide) and PAT protein (confers tolerance to glufosinate herbicide) with TriatChek lateral flow test strips (SDIX, Newark, DE). Each tested specimen was then archived at the University of Arkansas.
Results: One year later, and around 3,000 miles later, the group obtained clear evidence that genetically modified, feral canola is growing across much of North Dakota. Of the 406 samples collected, 347, or 86 percent of the specimens, were genetically altered versions of the plant. These observations indicate feral populations are reproducing and have become established outside of cultivation making this is the first report in the U.S. of established populations of genetically modified organisms in the "wild".
This study seems to be highly reputable, with researchers from universities such as the University of Arkansas and North Dakota State University, as well a the inclusion of the US Environmental Protection Agency. Resistant Insect Pests Resistance evolves naturally after a population has been subjected to intense selection pressure in the form of repeated use of a single herbicide or insecticide.
Article: Hardy Cotton-Munching Pests Are Latest Blow to GM Crops by Pallava Bagla A company in India, Monsanto, found that during a filed monitoring session of their 2009 crop, that discover large number of pink bollworm from Bollgard cotton, a crop that expresses a single Bt protein. The insects were brought to a lab and fed Bt toxins at normally lethal concentrations.
Results: The bollworms survived signifying that they had grown resistant to the type of genetically modified Bollgard cotton planted.
Although the results are interesting and realistic, Monsanto is a company that sells cotton and explained that they wanted to shift their crop to a newer, more resistant type of cotton, which is more expensive as well. Questions can be raised since one may not know that Monsanto is revealing true results, or setting up an excuse on raising their prices. Bibliography Health In this article doctors are urging patients to avoid eating genetically modified foods because of the negative effect they have on people, especially on pregnant women and babies. In a study done on rats it was found that when genetically modified foods were fed to female rats a majority of their offspring died within a few weeks. this was unlike the rats who were not given genetically modified food where the death rate of the babies was 10%. In addition, the babies of the experimental group were also smaller and those who were female eventually had problems getting pregnant. It was found that on rats that were given genetically modified foods their kidneys had lesions, toxicity, altered enzymes production, or inflammation. In addition, in rats fed genetically modified potatoes they had slower brain growth. Moreover, in mice who were fed genetically altered foods it was noticed that there sperm cells had been altered. New allergens can be introduced; people who have prior allergies can develop allergic reactions to foods that have been genetically modified. The reason why is because genetically modifiefoods involve the transferring of genes and if a gene is transferred from a food that someone may have an allergic reaction to, then the genetically modified food may cause an allergy. Genetically modified foods can be used to provide people with nutrients or certain chemicals which would prove beneficial to their health. For instance, in studies done amongst cancer prone mice it was found that providing them with purple tomatoes lengthens their lives. In fact, their lifespan was found to have increased by 30%. One of the first genetically modified crops known as "Golden Rice" has proven beneficial in confronting a deficiency among those who eat it. This deficiency involves Vitamin A, which without can result in blindness, diseases and an increase in death among children. However, by genetically modifying this food this issue has been addressed. In fact, in a simulation it was shown that this food could reduce problems associated with this deficiency by up to 60% in populations that commonly eat rice. When considering a new policy, you need to weigh the benefits and risks to do what is better overall. Different people have different values. Depending on the group, certain opinions will be heard. New inventions always have some risk associated with them. There are some unknown effects of experiments and scientific discovery depends on the pursuit of new knowledge. Bagla, Pallava. "Hardy Cotton-Munching Pests Are Latest Blow to GM Crops." Science Magazine. N.p., 19 Mar. 2010. Web. 26
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