A professor who frequently testifies against Monsanto Co. in lawsuits alleging harm from toxic environmental pollutants called PCBs says that after a Monsanto lawyer filed a records request with his university, the university barred him from campus and offered him a resignation deal. “That was the very first thing that they gave me,” said the Professor, Dr. David Carpenter of the University at Albany, part of the State University of New York, regarding the resignation offer.