Agrochemicals like pesticides, fertilisers, insecticide, fungicides, weedicides, etc.  destroy the ecosystem of the soil. Fertilisers cause soil deterioration through decrease of natural microflora. Leaching down of these chemicals causes pollution of underground water. Salts of different compounds used for in crop plants may prove harmful eg. Nitrate rich leaves, fruit and water produce nitrate in the Alimentary Canal that enters blood, combines with Hb to form met-haemoglobin and reduces oxygen transport. It may prove fatal.