Technology came out good and bad effects what is a bad effect of spraying pesticides on crops with the use of airplanes

Although pesticides eventually kills the pests, should an animal eat multiple of the poisoned pest, the will have a higher amount of pesticide in them. This continues up the food chain until either the dominant predator or humans are eating these pesticides. So by trying to prevent animals from eating crops with pesticides, we consume way more pesticide than the original animal.