In the 1970s, the U.S. government sprayed paraquat, a toxic herbicide, on cannabis fields in Mexico to help eradicate marijuana. This controversial program led to concerns about the health risks associated with inhaling paraquat-contaminated marijuana; 'COUNTRY JOE' MCDONALD DIES AT 84 AFTER BATTLING PARKINSON'S DISEASE FOR YEARS; EPA The agency also looked at concerns that paraquat causes Parkinson's; This is why i was against legalizing Weed , it gave control over it to the gov. They can dictate what goes on it. FOLLOW THE SCIENCE KIDS; I heard Joe smoked a lot of Weed in the 70's. 'Your gov. would never hurt you.'