Complex sentence: The existence of conspiracy theories relating to the fear over GMOs has been attested to by scientists, journalists, and skeptics who oppose much anti-GMO activism, but academics writing about bioethics and science communication have also taken note.
Split into simpler sentences: The existence of conspiracy theories relating to the fear over GMOs has been attested to by scientists, journalists, and skeptics who oppose much anti-GMO activism. Academics writing about bioethics and science communication have also taken note.