WASHINGTON (AP) — One of the biggest stumbling blocks to securing a massive free trade agreement between the United States and Europe is a sharp disagreement on genetically modified foods.


Much of the corn, soybean, sugar beets and cotton cultivated in the United States today contains plants whose DNA was manipulated in labs to resist disease and drought, ward off insects and boost the food supply. Though common in the U.S., they are largely banned in the 28-nation European Union.


Washington wants Europe to ease restrictions on imports of these foods, commonly known as GMOs for genetically modified organisms, but the EU is skeptical they are safe. Intense emotions on both sides of the divide make it difficult to separate between strongly held belief and science.


A look at key points in the debate:


SAFE OR UNSAFE?


Most studies show genetically modified foods are safe for human consumption, though it is widely acknowledged that the long-term health effects are unknown. The Food and Drug Administration generally recognized these foods as safe, and the World Health Organization has said no ill health effects have resulted on the international market.


Opponents on both sides of the Atlantic say there has been inadequate testing and regulation. They worry that people who eat genetically modified foods may be more prone to allergies or diseases resistant to antibiotics. But they have been hard pressed to show scientific studies to back up those fears.



GM foods have been a mainstay in the U.S. for more than a decade. Most of the crops are used for animal feed or in common processed foods such as cookies, cereal, potato chips and salad dressing.


Europe largely bans genetically engineered foods and has strict requirements on labeling them. They do allow the import of a number of GM crops such as soy, mostly for animal feed, and individual European countries have opted to plant these types of crops. Genetically engineered corn is grown in Spain, though it amounts to only a fraction of European farmland.


The American Medical Association favors mandatory, pre-market safety testing, something that has not been required by U.S. regulators. The WHO and the U.N. food agency, the Food and Agriculture Organization, say the safety of genetically modified foods must be evaluated on a case-by-case basis.


CAN GM FOOD HELP COMBAT WORLD HUNGER?


By 2050, the world's population is projected to rise to 9 billion from just over 7 billion currently. Proponents of genetically modified foods say they are safe and can boost harvests even in bad conditions by protecting against pests, weeds and drought. This, they argue, will be essential to meeting the needs of a booming population in decades to come and avoiding starvation.


However Doug Gurian-Sherman, senior scientist for the food and environment program at the Union of Concerned Scientists, an advocacy group, said genetic engineering for insect resistance has provided only a modest increase in yields since the 1990s and drought-resistant strains have only modestly reduced losses from drought.


Moreover, he said conventional crossbreeding or cross-pollinating of different varieties for desirable traits, along with improved farming, are getting better results boosting yields at a lower cost. In fact, much of the food Americans eat has been genetically modified by those conventional methods over thousands of years, before genetic engineering came into practice.


"Overall, genetic engineering does not get nearly the bang for the buck as conventional breeding" and improved agricultural practices, Gurian-Sherman said. His organization advises caution on GM foods and favors labeling, though it acknowledges the risks of genetic engineering have sometimes been exaggerated.


Andrea Roberto Sonnino, chief of research at the U.N. food agency, said total food production at present is enough to feed the entire global population. The problem is uneven distribution, leaving 870 million suffering from hunger. He said world food production will need to increase by 60 percent to meet the demands of 9 billion by 2050. This must be achieved by increasing yields, he added, because there is little room to expand cultivated land used for agriculture.


Genetically modified foods, in some instances, can help if the individual product has been assessed as safe, he said. "It's an opportunity that we cannot just miss."


TO LABEL OR NOT TO LABEL?


Europe requires all GM food to be labeled unless GM ingredients amount to 0.9 percent or less of the total. The U.S. does not require labels on the view that genetically modified food is not materially different than non-modified food. Opponents of labeling say it would scare consumers away from safe foods, giving the appearance that there is something wrong with them.


U.S. activists insist consumers should have the right to choose whether to eat genetically modified foods and that labeling would offer them that choice, whether the foods are safe or not. They are pushing for labeling at the state and federal level. California voters last year rejected a ballot initiative that would have required GM food labeling. The legislatures of Connecticut and Maine have passed laws to label genetically modified foods, and more than 20 other states are contemplating labeling.


COULD GM FOOD TORPEDO THE TRADE DEAL?


Absolutely. The U.S is pressing for the restrictions on importing genetically modified food to be eased but there is no sign that the EU's firm opposition is softening. German Chancellor Angela Merkel said recently that Europe will defend its restrictions in the trade negotiations, which began last month. Some in the U.S. see the European resistance as just another form of protectionism that promotes domestic products over imported ones.


GM foods are not the only seemingly intractable issue standing in the way of a comprehensive free trade agreement to remove most tariffs and other trade barriers, aiming to boost jobs and growth. Genetically modified foods are part of a broader set of restrictions on both sides related to agriculture and food safety. There are also significant differences on intellectual property and financial regulations, among other thorny issues.



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  • A picture taken on October 9, 2008 shows an ultralight helicopter hovering above a field where Greenpeace activists and Austrian organic farming association BIO AUSTRIA wrote the message 'NO GMO' (Genetically Modified Organism) by planting light green coloured organic buckwheat in a field of organic peas in Breitenfurt, some 60 kms south east from Vienna. (DIETER NAGL/AFP/Getty Images)




  • Thirty-five tons of corn put by Greenpace activists at Mexico City's Zocalo Square as a protest against the sowing of transgenic corn, form a map of Mexico on February 26, 2009. (Ronaldo Schemidt/AFP/Getty Images)




  • People walk on a plateform past an advert against genetically modified (GMO) food on February 15, 2011 at a subway station in Paris. (MIGUEL MEDINA/AFP/Getty Images)




  • Greenpeace activists demonstrate against genetically modified organisms (GMOs) on November 24, 2008 in front of EU headquarters in Brussels. Greenpeace called on the European Union to suspend the authorization of GMOs until the EU is capable of evaluating the risks they pose. (DOMINIQUE FAGET/AFP/Getty Images)




  • Greenpeace activists stand a protest in front of Los Pinos presidential residence in Mexico City against the farming of transgenic corn in Mexico, on June 26, 2009. (ALFREDO ESTRELLA/AFP/Getty Images)




  • A Greenpeace activist impersonating Brazil's Chief of Staff Dilma Russeff takes part in a protest against the authorization to grow transgenic rice during a meeting of the National Biosecurity Technical Commission (CYNBIO) at the Science and Technology Ministry in Brasilia October 15, 2009. (JOEDSON ALVES/AFP/Getty Images)




  • Greenpeace activists distribute samples of transgenic rice as part of a protest against the authorization to grow transgenic rice during a meeting of the National Biosecurity Technical Commission (CYNBIO) at the Science and Technology Ministry in Brasilia October 15, 2009. (JOEDSON ALVES/AFP/Getty Images)




  • The logo of French 'Les faucheurs volontaires' (Volunteer trimmers of GMO) is seen as demonstrators stand in front of the booth of French union 'la confederation paysanne' (farmers union) during an action against GMO at the International Agricultural Fair on March 6, 2010 in Paris. The European Commission authorised, on March 2, the cultivation of a genetically modified potato, developed by BASF, the first such green light for 12 years. The issue of so-called 'frankenfoods' has long been a matter of fierce debate in Europe and the commission stressed that the Amflora potato in question would be able to be grown only for 'industrial use' including animal feed, rather than for human consumption. (BERTRAND LANGLOIS/AFP/Getty Images)




  • A couple waves after a parody of union between German chemical giant BASF (L) and the European Food Safety Authority (R) - Autorite europeenne de securite des aliments- (EFSA) during the International Agricultural Fair on March 6, 2010 in Paris. (BERTRAND LANGLOIS/AFP/Getty Images)




  • A giant banner depicting a farm, is seen as Greenpeace activists hold banners to protest against the genetically modified (GMO) food production in front of the parliament building of Budapest on February 10, 2010. (ATTILA KISBENEDEK/AFP/Getty Images)




  • A grey-cow is pictured near Greenpeace activists in traditional Hungarian costume standing in front of a giant banner depicting a farm as others hold a banner reading 'GMO-free Europe' to protest against the genetically modified (GMO) food production in front of the parliament building of Budapest on February 10, 2011 during a demonstration. (ATTILA KISBENEDEK/AFP/Getty Images)




  • Greenpeace activists hold a banner to protest against the genetically modified (GMO) food production in front of the parliament building of Budapest on February 10, 2010. (ATTILA KISBENEDEK/AFP/Getty Images)




  • A man dressed up as a bee holds a placard during a demonstration organized by French Professional Beekeepers Federation (FFAP) to protest against the use of pesticide on September 14, 2011 along the Saint-Bernard quay in Paris. (JACQUES DEMARTHON/AFP/Getty Images)




  • Anti-Genetically Modified Organisms (GMO) demonstrators protest in front of Colmar courthouse on September 28, 2011, eastern France, during the trial of 60 militants accused of destroying MGO plants. (FREDERICK FLORIN/AFP/Getty Images)




  • An anti-GMO activist holds a banner reading 'Science without conscience is but the ruin of soul' during an action to call for the ban of the 'MON 810', a variety of genetically modified maize (corn) developed by Monsanto Company on January 23, 2012 at a Monsanto storehouse in Trebes near Carcassonne, southern France. (ERIC CABANIS/AFP/Getty Images)




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