There are other alternatives than use a herbicide that kills a certain number of people. The thing is that massive multi-billion dollar companies absolutely try to sabotage any consideration of the safety of their pesticides, because it's so much money to them. If you are a researcher, you'll be getting into a fraught area if you are doing a study to validate it's safety. It's similar to looking into climate science - the crazies will come for you, and probably the pseudo-non-climate-scientist people taking money from exxon.