There have been numerous lawsuits by those who claim it gave them non-Hodgkin’s lymphoma. This is the question being asked by homeowners, gardeners, and other people who use the popular Monsanto-made weed killer. Is glyphosate (Roundup) dangerous? What are we to make of the ‘Séralini studies’ claiming GMOs and glyphosate are dangerous? Since then, Roundup manufacturer Monsanto (purchased by Bayer) has been battling thousands of lawsuits alleging that the product caused non-Hodgkin’s lymphoma.