Q: How long was Monsanto's study of GMOs, before they were "deemed" safe? How long was the longest study? Question Submitted By: Veronica from Juarez, Chihuahua Notification Preferences +1 +2 -1 Thank you for your question. One of our experts will get back to you soon. Topic: Safety, Health, and Nutrition 0 Comments | Add Comment Log in or register to post comments To post a comment, please login.