If leeches are on people's bodies, you can gently pat the surrounding skin, or use salt water, soapy water, vinegar, etc. to let leeches come down from the body. Be careful not to pull them out by hand. If leeches are in farmland, the use of drugs will have a certain impact on crops, and lime powder can be used. Lime powder can not only kill leeches, but also disinfect the soil.
Sprinkling dry lime powder is the most effective and pollution-free method to kill leeches. Although it is very effective to kill with highly toxic pesticides, there will be pesticide residues that will also have an impact on farmers and future plants. The effect of using dichlorvos with low toxicity and low residue is not ideal.