Work on the 388-page report began two years ago and was conducted by a committee of more than 50 scientists, researchers and agricultural and industry experts convened by the National Academies of Sciences, Engineering, and Medicine. It reviewed more than 900 studies and data covering the 20 years since genetically modified crops were first introduced.
Overall, genetically engineered (GE) crops saved farmers in the United States money but didn’t appear to increase crop yields. They have lowered pest populations in some areas, especially in the Midwest but increased the number of herbicide-resistant weeds in others. There’s also no evidence that GE crops have affected the population of monarch butterflies, the report said.
The review was thorough and systemic, assessing many of the issues that have been raised about genetically engineered crops over the years, said Gregory Jaffe, director of biotechnology at the non-profit watchdog group the Center for Science in the Public Interest in Washington D.C. The group was not involved in the report's creation.