It seems as though the food industry is becoming more and more transparent, stamping labels on packages that practically scream everything from "vegan" to "gluten free" to "all natural."

The one aspect that you won't find indicated on a label, however, is whether or not the product contains a GMO, or a genetically modified organism.The term refers to any plant or animal that has been genetically engineered with DNA from other plants, animals, bacteria and viruses.The first plant to be genetically modified in a laboratory was a tomato, about 20 years ago.Today, approximately 80 percent of processed foods have genetically modified ingredients, like breakfast cereals, vegetable oils and dairy products.The purpose of engineering our food's DNA is mainly due to productivity.GMOs require less water to grow twice the crop yield, are more resistant to pests, are more tolerant to harsh weather conditions and they provide the opportunity for growers to inject certain nutrients into them, which can be used in Third World countries where adequate nutrition is hard to come by.It's even become possible to inject certain vaccines into these foods.Also, GMOs are resistant to weedkillers, making it unnecessary for farmers to laboriously pluck weeds from the ground.In other words, less labor means lower costs.However, there are a number of concerns that arise with GMOs.Environmentally speaking, the pesticides used for GMO crops have caused harm to organisms other than pests, and some organisms are becoming resistant to pesticides.It is also possible that GMO crops and weeds will cross breed, resulting in a weed that is resistant to herbicides.In regard to human health, introducing a new gene into a particular plant provides the potential for more allergic reactions.Overall, the long-term effects of GMOs on human health are unknown.For groups like GMO Free PA, these loose ends are reason enough to advocate mandatory GMO labeling on foods sold in the state.Audra Wallis, a member of the Lehigh Valley chapter, joined the organization about a year ago when she researched GMOs."Honestly, I was angered by the fact that these corporations were putting this in our food supply without our knowledge or consent," Wallis said.GMO Free PA, formed in April 2013, has 10 chapters throughout the state which hold marches and meetings to educate the public."It's a grass-roots movement that's been gaining momentum," Wallis said.However, Karen Batra, director of communications for the Biotechnology Industry Organization, said that there is a lot more involved than stamping a label on a box of cereal, and that GMO labels would mislead consumers."Distinguishing these products is implying some kind of safety or health difference," Batra said. "That label doesn't really convey any valuable information to the consumer."Batra said that consumers already have the choice not to purchase genetically modified foods by choosing products labeled "certified organic."She added that safety standards are already in place, requiring nutritional information as well as ingredients on food labels.Between the Environmental Protection Agency, the U.S. Department of Agriculture and the Food and Drug Administration, foods are evaluated to be safe for both the environment and the consumer.The back-and-forth labeling debate doesn't seem to be coming to a stop anytime soon.Both sides, it seems, are using the same argument regarding the possibility of negative effects on human health: There is no proof.