Well, wind drift is going to be a problem, and it kills the bad bugs, but the good ones as well. If anyone is in that field when the crop duster lets his spray go, then one would be covered in it. In countries other than the USA, like in Mexico, and such, they still use pesticides like DDT, and Chlordane, without any regards or concerns about the safety of the migrant workers. Unfortunately these crops make their way back into the USA. They still use that stuff in China. It is what is called a chlorinated hydrocarbon, and they are the most persistent poison in the environment. I watched a show once where the workers were mixing up crop chemicals with no safety gear on, and they didn't know if they were using the correct label rates either, as the directions were in English, and they only understood Spanish. Pesticides can be beneficial IF used correctly, and that means following the label directions to the letter! Don't skimp on safety either. Its your health, not mine.