Milkweed, the monarch's primary food source, commonly grows alongside corn. Researchers in Europe have made similar discoveries involving ladybugs and green lacewings, both beneficial insects. Yet another study, reported in 1997 in the British publication New Scientist, indicates that honeybees may be harmed by feeding on proteins found in genetically engineered canola flowers. Microbiologists at New York University have found that the BT toxin in residues of genetically altered corn and rice crops persists in soils for up to 8 months and depresses microbial activity. And in another study, scientists in Oregon tested an experimental genetically engineered soil microbe in the laboratory and found it killed wheat plants when it was added to the soil in which they were grown.
Proteins are also common sources of human allergies.
But some scientists worry that this process could compound the increasingly serious problem of antibiotic resistant bacteria. The concern is that bacteria living in the gut of humans or animals could acquire antibiotic resistance from GMO foods eaten by the human or animal, possibly rendering treatments for such infections as meningitis and gonorrhea ineffective. People who choose not to eat animals for religious or moral reasons face an almost impossible task with many genetically engineered foods. Which will defeat the purpose of engineering the plants and may coax farmers into using more powerful poisons to kill weeds. Farmers who use this patented technology, meanwhile, are prohibited from the self-sufficiency of saving seed and instead are forced into a costly cycle of corporate dependency.