Pesticide residue development
The problem of pesticide residues is produced with the extensive production and extensive use of pesticides. Before the Second World War, the pesticides used in agricultural production were mainly inorganic compounds such as arsenic or sulfur, lead and copper, as well as pyrethrin, nicotine and other organic compounds from plants. During the Second World War, synthetic organic pesticides began to be used in agricultural production. So far, the world's annual output of chemical pesticides is nearly 2 million tons, and about 1000 kinds of synthetic compounds have been used as pesticides, fungicides, algicides, insecticides, defoliant and other pesticides. The application of pesticides, especially organic pesticides, has caused serious problem of pesticide pollution and has become a serious threat to human health.