The rapid adoption by U.S. farmers of genetically engineered corn, soybeans and cotton has promoted increased use of pesticides, an epidemic of herbicide-resistant weeds and more chemical residues in foods, according to a report ... by health and environmental protection groups. The groups said research showed that herbicide use grew by 383 million pounds from 1996 to 2008, with 46 percent of the total increase occurring in 2007 and 2008. The report was released by nonprofits The Organic Center (TOC), the Union for Concerned Scientists (UCS) and the Center for Food Safety (CFS). The groups said that [there is] a net overall increase on U.S. farm fields of 318 million pounds of pesticides, which includes insecticides and herbicides, over the first 13 years of commercial use. The rise in herbicide use comes as U.S. farmers increasingly adopt corn, soy and cotton that have been engineered with traits that allow them to tolerate dousings of weed killer. The report by the environmental groups states that a key problem resulting from the increase in herbicide use is the emergence of "super weeds," which are difficult to kill because they have become resistant to the herbicides. "This report confirms what we've been saying for years," said Bill Freese, science policy analyst for the Center for Food Safety. "The most common type of genetically engineered crops promotes increased use of pesticides, an epidemic of resistant weeds, and more chemical residues in our foods. This may be profitable for the biotech/pesticide companies, but it's bad news for farmers, human health and the environment."