They are. one of my neighbors can't stand any form of what he calls a weed and uses dioxin and a even a substance that has been deemed hazardous and pulled from the market (I can't remember what it is right now) I don't respond well to chemicals. I get headaches and get sick. So when I sprays ...I have to make sure my windows are shut and the swamp cooler is off. It really sucks since I sleep during the day.